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Home My WebLink About2009 05 11 Regular 601 TMDL Master PlanCOMMISSION AGENDA ITEM 601 May 11, 2009 Meeting CONSENT INFORMATIONAL PUBLIC HEARING REGULAR X ;. ,r, ;%. MGR ~ /DEPT ~ Authorization REQUEST: Public Works Department - Stormwater Division requesting the City Commission adopt the Total Maximum Daily Load (TMDL) Master Plan for Lake Jesup. PURPOSE: The purpose of this agenda item is to request the City Commission adopt the Total Maximum Daily Load (TMDL) Master Plan for Lake Jesup. LAKE JESUP TMDL BACKGROUND: • A Total Maximum Daily Load, or TMDL, refers to the maximum amount of a pollutant that a water body can assimilate without causing exceedances of water quality standards.. Water bodies having exceedances of water quality standards are identified by the State as impaired. • Lake Jesup has been verified by the Florida Department of Environmental Protection (FDEP) as impaired for nutrients and unionized ammonia due to elevated annual average Trophic State Index (TSI) values and exceedances of the unionized ammonia criterion. FDEP formally adopted a Total Maximum Daily Load (TMDL) report for Lake Jesup in April 2006. The TMDL report identified the nutrient loading sources and required reductions to meet water quality standards for total phosphorous (TP) and total nitrogen (TN) within the Lake Jesup Basin. TMDL MASTER PLAN BACKGROUND: • At the January 14, 2008 City Commission meeting, the Commission provided authorization to enter into a contractual agreement with Camp Dresser & McKee Inc. (CDM) to provide professional engineering services for the development of a Lake Jesup Total Maximum Daily Load (TMDL) Master Plan. The Master Plan is complete and this agenda item is requesting its adoption by the City Commission. May 11, 2009 Agenda Item #601 Page 2 of 7 • The purpose of the Total Maximum Daily Load (TMDL) Master Plan is to identify, price, and prioritize the projects, activities, and policies that the City can implement in order to meet its TMDL obligations for Lake Jesup. CITY OBLIGATIONS FOR REDUCED PHOSPHOROUS DISCHARGE TO LAKE JESUP FROM STORMWATER RUNOFF: The Lake Jesup Basin Stakeholders are currently finalizing a Basin Management Action Plan, or BMAP, to reduce the amount of nutrients that caused the verified impairment of Lake Jesup. Under the BMAP, entities within the Lake Jesup Basin including the City of Winter Springs will be required by the Florida Department of Environmental Protection to reduce phosphorous discharges to Lake Jesup from surface waters and/or septic systems by a combined total of approximately 15,000 pounds over the next 15 years. The City of Winter Springs will be required to reduce its phosphorous discharEe by approximately 756 pounds over the next 15 years under the current BMAP, which is in its final development stages but has not been formally adopted. • A summary of the draft final reduction responsibility by entity is as follows: ntity Total Phosphorous Discharge Reduction Required (Ibs) Over the Next 15 Years of Total Seminole Coun 5,025.8 33.4% Oran a Coun 1,676.4 11.1 Sanford 1,435.1 9.5% Winter Park 962.7 6.4% Casselberry 949.1 6.3% Winter Springs 755.6 5.0% A riculture 751.8 5.0% Lake Mary 714.6 4.7% Lon wood 670.1 4.5% Maitland 584.1 3.9% Oviedo 416.1 2.8% Orlando 358.9 2.4% FDOT District 5 299.4 2.0% Florida's Turn ike 265.6 1.8% Eatonville 120.4 0.8% Altamonte S rin s 45.3 0.3% OOCEA 16.0 0.1 LAKE JESUP BASIN TOTAL 15,047.0 May 11, 2009 Agenda Item #601 Page 3 of 7 • The City's 755.6 pound reduction is expected to be required over the next 15 years in accordance with the following schedule: Total Phosphorous Reduction b Time Period 2009-14 2015-2019 2020-2024 TOTAL 0.0 241.5 514.1 755.6 The required reductions were spread over the next 15 years in order to reduce the short- term cost burden and to allow additional scientific studies of the Lake to be completed and incorporated into the BMAP as warranted. TMDL MASTER PLAN SUMMARY: • The TMDL Master Plan is a comprehensive 120-page report covering the following topics: o City Stormwater System Review o TMDL Data Collection and Review o Pollutant Load Source Identification o Recommended Structural Pollutant Load Reduction Strategies o Recommended Non-Structural Pollutant Load Reduction Strategies o Pollutant Load Summary o Recommended Project Ranking and Prioritization • The complete report is available on the City website under "Public Notices" at the link titled "Lake Jesup TMDL Master Plan." A hard copy is also available for review at the City Clerk's office. • The TMDL Master Plan identified thirteen (13) conceptual phosphorous-reducing projects and activities and evaluated each for available phosphorous reduction, construction cost, permittability, and maintenance effort. Staff has taken the project data and recommendations from the TMDL Master Plan and formulated the prioritized project list shown on Table 1 (see following page). • The total available phosphorous removal from the 13 projects listed in Table 1 is 786.7 pounds per year, which exceeds the City's obligated reduction amount of 755.6 pounds per year. However, as shown in Table 1, some of the projects are extremely costly in terms of cost per pound of phosphorous removed. Only the top eight (8) projects are recommended for implementation, which would provide an estimated total combined reduction of 733.4 pounds of phosphorous per year, just under the required 755.6 lbs/year. It is anticipated that over the 15-year implementation period, the City will have opportunities to participate in regional stormwater projects in order to fully meet its obligation and to reduce the total cost of the program. • The five "Additional Projects" listed in Table 1 are not expected to be implemented although the project concepts could be further evaluated if necessary. Table 1 TMDL Master Plan -Prioritized Projects List Annual TP Removal Cumulative Construction Cost per pound Rank Pro'ect Ibs TP Removal Cost of TP Removed Recom mended Projects: 1 Solary Canal 314.0 314.0 $0 $0 2 Local Codes and Ordinances Fertilizer Rule, etc. 34.5 348.5 $0 $0 3 Street Sweepin 7.3 355.8 $0 $0 4 Florida Yards & Nei hborhoods 80.5 436.3 $3,000 $37 5 Windin Hollow Wetland Treatment Area 201.7 638.0 $357,000 $1,770 6 Winter S rin sand Wed ewood Filtration Devices 25.7 663.7 $132,000 $5,136 7 North Orlando Townsite Filtration Devices 5.2 668.9 $80,000 $15,385 8 Hi hlands Pond Im rovements 64.5 733.4 $1,385,000 $21,473 Total Reduction 733.4 $1,957,000 $2,668 Total TMDL TP Allocation throu h 2024 755.6 Additio nal Projects: 9 Oak Forest Filtration Devices 5.4 738.8 $194,000 $35,926 10 Tuscawilla CC Stormwater Reuse and Water Features 33.5 772.3 $1,466,000 $43,761 11 Winter Sprin s Blvd Pond Enhancements 1.5 773.8 $250,000 $166,667 12 Hacienda Village Stormwater Facility 3.5 777.3 $1,276,000 $364,571 13 Buttonwood Ave Stormwater Pond 9.4 786.7 $3,613,000 $384,362 TMDL PROJECT DESCRIPTIONS: The thirteen (13) conceptual phosphorous reducing projects are more specifically described as follows. The top eight (8) projects listed below are recommended for implementation to meet the City's TMDL obligations. 1. Solaro Canal - A proposed regional Stormwater Treatment Area located on a 28.9- acre property at 1900 DeLeon Street in the northeast corner of the City of Winter Springs. The Stormwater Treatment Area is comprised of a manmade wet pond and wetland connected in series. The project is estimated to remove a total of 942 pounds of phosphorous per year. The reduction available to the City of Winter Springs is expected to be 314 pounds per year, based on a planned partnership with the City of Oviedo and Seminole County. The Final Engineering for Solary Canal was approved by the City Commission at the September 22, 2008 meeting. Construction bids opened on April 29, with a low base bid of $1.23 million. An Interlocal Agreement is being drafted by the project partners and this is expected to be submitted to the City Commission for approval within the next 60 days. 2. Local Codes and Ordinances -TMDL credit is available for the adoption of local land development codes or ordinances that require Florida Friendly landscaping on all new developments, require commercial landscapers to obtain training and certification through the Green Industry BMP program, require irrigation systems per current law and which specify fertilizer application rates and types. This activity also includes local ordinances that control pet waste and other public education activities such as public service announcements, pamphlets, and website communications. The City of Winter Springs is already doing some of these activities, and the City can obtain up to 34.5 pounds per year of TMDL credit for full compliance. 3. Street Sweeping -The City's current street sweeping program consists of sweeping all City streets on a quarterly basis. Maintaining this program at its current level will provide 7.3 pounds per year of TMDL credit. 4. Florida Yards and Neighborhoods (FYN) -The City started participating in the FYN program this year at a cost of $3,000 per year. The FYN Program is administered by Seminole County through the. University of Florida/Institute of Food and Agricultural Sciences (UF/IFAS) Cooperative Extension Service Office. The FYN program provides environmental education and outreach activities in the community to help residents reduce stormwater runoff conserve water and enhance their community by improving home and landscape management. The City hosted a FYN Public Workshop on Florida Friendly Landscaping on April 16, 2009. Approximately 75 people attended the workshop. Continued participation in FYN provides 80.5 pounds per year of TMDL credit. 5. Winding Hollow Wetland Treatment Area -This project proposes stormwater improvements between Winding Hollow and North Orlando Ranches (east of Mockingbird Lane) consisting of the following: a. Rehydrate the 31-acre wetland on City-owned property May 11, 2009 Agenda Item #601 Page 6 of 7 b. Re-route the underdrain discharges on the west side of Winding Hollow north into the wetland area c. Construct an overflow weir to divert flow from No Name Creek into the wetland treatment system d. Install baffle boxes for pre-treatment and a control structure to re-hydrate and regulate discharge from the wetland system. 6. Winter Springs and Wedgewood Filtration Devices -This project consists of retrofitting six (6) existing stormwater outfalls that currently discharge directly into Howell Creek with flow-through filtration devices. The outfalls are located in Winter Springs Units 2 and 3 and at the Wedgewood Golf Villas. 7. North Orlando Townsite Filtration Devices -The subdivision east of Sherry Avenue, south of George Street, west of Wade Street, and north of SR 434 does not have stormwater treatment in place. This project proposes to retrofit the existing stormwater outfalls with flow-through filtration systems. 8. Highlands Pond Improvements -This project consists of the expansion of the existing wet detention pond located at the northeast corner of The Highlands, north of Shepard Road. The existing pond is not achieving optimal pollutant removal efficiency due to a lack of adequate treatment volume. This project would expand the pond area to approximately 3.5 acres and modify the control structure for improved performance. The project also includes redirecting all or a portion of the drainage from Highlands Section 1 to the improved pond. The following projects were evaluated as part of the TMDL Master Plan but are not recommended for implementation due to their high costs or other factors that make them infeasible. 9. Oak Forest Filtration Devices - Project consists of retrofitting six existing stormwater outfalls in Oak Forest that currently discharge directly into the Little Lake Howell tributaries with flow-through filtration devices. 10. Tuscawilla Country Club Stormwater Reuse and Water Features - The Tuscawilla Country Club is a good area for stormwater retrofits because it currently has minimal stormwater treatment facilities and it discharges untreated stormwater runoff directly into Howell Creek, which runs through the golf course. This project consists of converting the existing wet detention ponds on the golf course property into stormwater reuse ponds that would be used for irrigating the golf course. The project also includes construction of water features (small wet detention ponds) adjacent to Howell Creek that will capture runoff from the golf course. This project was not cost effective but warrants additional analysis. 11. Winter Springs Blvd Pond Enhancements -The existing pond located on the north side of Winter Springs Blvd adjacent to Bear Creek is not functioning at optimal treatment efFciency and it has historically been difficult to maintain good water quality in this pond. The pond continuously discharges into Bear Creek. This proposed project would increase the size and depth of the pond by connecting it to the pond May 11, 2009 Agenda Item #601 Page 7 of 7 immediately to the north serving Chestnut Estates. The existing control structure would be relocated and modified to improve performance. This project was not cost effective overall but portions of it could still be worthwhile. 12. Hacienda Village Stormwater Facility -Hacienda Village was built with no stonnwater treatment facilities. and runoff from this community dischazges directly into Gee Creek. This proposed project consists of a 1.6-acre lineaz detention pond along the north banks of Gee Creek within Hacienda Village and retrofitting existing stonnwater outfalls along both the north and south sides of Gee Creek with flow- through filtration devices. This project is not recommended due to its high cost, minimal phosphorous removal, and permitting challenges. 13. Buttonwood Avenue Stormwater Pond -The North Orlando Terrace and North Orlando Second Addition subdivisions have minimal stonnwater treatment facilities and stonnwater runoff dischazges directly into Gee Creek. This project proposes the construction of a 4.1-acre wet detention pond on an existing City-owned pazcel located south of Buttonwood Avenue and north of Camphorwood Street. The project also includes re-routing existing drainage in the subdivision into the proposed pond and providing a control structure that directs pond overflow into the tn~utary north of Alderwood Street. This project was not recommended due to its high cost and limited treatment capability. FUNDING: No funding is requested. Funding for individual projects would occur as a part of the normal budgeting and approval process. RECOMMENDATION: Staffrecommends the City Commission adopt the Total Maximum Daily Load (TMDL) Master Plan for Lake Jesup including the prioritized project list contained herein. ATTACHMENTS: The complete TMDL Master Plan report is available on the City website under "Public Notices" at the link titled "Lake Jesup TMDL Master Plan." A hazd copy is also available for review at the City Clerk's office. COMMISSION ACTION: Date: May 11, 2009 The attached was referenced in Regular Agenda Item "601" during the May 11, 2009 Regular City Commission Meeting. City of ~'~' LL' L~ i_ ~ L~ L LL~_~~ ~ ~ ~~ L i-~~~_l'- Total Maximum Daily Load (TMDL) Master Plan _~«~-- ;.::~,; ~:~, ~ ; LETTER REPORT Contents 1.0 Background ............................................................................................................................1 2.0 City Stormwater System Review .......................................................................................1 2.1 Stormwater Master Plan ............................................................................................. 3 2.2 Stormwater System Infrastructure Inventory .......................................................... 3 2.2.1 Existing Best Management Practices (BMPs) within the City ................ 4 2.2.2 Field Review .................................................................................................. 4 2.3 Sanitary Sewer and Septic Tank Data ....................................................................... 8 2.4 Reclaimed Water System ..........................................................................................10 2.5 NPDES MS4 Permit ...................................................................................................10 2.6 Comprehensive Plan and Code of Ordinances .....................................................12 2.7 Stormwater Funding Sources ...................................................................................13 3.0 TMDL Data Collection and Review ................................................................................14 3.1 TMDL Background ....................................................................................................14 3.2 Water Quality Data Review .....................................................................................17 3.2.1 Soldiers Creek .............................................................................................18 3.2.2 Gee Creek .................................................................................................... 22 3.2.3 Howell Creek .............................................................................................. 26 3.2.4 Bear Creek/Lightwood Knox Canal ........................................................ 29 3.2.5 Water Quality Summary ........................................................................... 32 4.0 Pollutant Load Source Identification ..............................................................................34 4.1 Underdrains ............................................................................................................... 35 4.2 Golf Courses ............................................................................................................... 37 4.3 Septic Tanks ................................................................................................................ 37 4.4 Reclaimed Water ........................................................................................................40 4.5 Street Sweeping .......................................................................................................... 45 4.6 Areas without Stormwater Treatment/Stormwater Facilities Requiring Improvements ........................................................................................................... 45 5.0 Recommended Structural Pollutant Load Reduction Strategies ...............................47 5.1 Soldiers Creek Subbasin ........................................................................................... 47 5.1.1 Highlands Subdivision Pond Enhancement ........................................... 47 5.2 Gee Creek Subbasin ................................................................................................... 53 5.2.1 Buttonwood Avenue Stormwater Facility .............................................. 53 5.2.2 Hacienda Village ........................................................................................ 56 5.2.3 N. Orlando Ranches Sections 2A, 9 & 10 & Winding Hollow Subdivision .................................................................................................. 60 5.2.4 North Orlando Townsite Subdivision ..................................................... 64 ~~ i S:\65898\63938\Report\Letter Report\TOC.docx Table of Contents City of Winter Springs TMDL Master Plan 5.3 Howell Creek Subbasin ............................................................................................ 66 5.3.1 Tuscawilla Country Club .......................................................................... 66 5.3.2 Winter Springs Boulevard Pond at Bear Creek ...................................... 70 5.3.3 Winter Springs and Wedgewood Subdivisions ..................................... 75 5.4 Little Lake Howell Subbasin .................................................................................... 77 5.4.1 Oak Forest Unit 2A, 2B & 3 ....................................................................... 77 6.0 Recommended Non-Structural Pollutant Load Reduction Strategies ......................79 6.1 Low Impact Development Practices ....................................................................... 79 6.2 Redevelopment .......................................................................................................... 82 6.3 Fertilizer Ordinance .................................................................................................. 84 6.4 Golf Courses BMPs .................................................................................................... 84 7.0 Pollutant Load Summary ...................................................................................................85 8.0 Recommended Project Ranking and Prioritization .....................................................86 8.1 Estimated Alternative Costs ..................................................................................... 86 8.2 Development of Ranking Criteria .......................................................................... 86 9.0 Summary and Conclusions ...............................................................................................90 10.0 References ...........................................................................................................................92 Attachment 1- StormFilter® Typical Sketch Attachment 2 -Conceptual Cost Estimates ~~ ii S:\65898\63938\Report\Letter Report\TOC.docx Table of Contents City of Winter Springs TMDL Master Plan Tables Table 1 Percentages of Simulated Runoff and Nutrient Loadings for the Lake Jesup Basin .................................................................................................. 15 Table 2 Lake Jesup BMAP Surface Runoff Allocation for Total Phosphorus ...................... 17 Table 3 Water Quality Data Summary ...................................................................................... 34 Table 4 Subdivisions with Septic Tanks in Close Proximity to Water Bodies .................... 40 Table 5 Estimated Nutrient Loading Due to Reclaimed Water Application ....................... 42 Table 6 Estimated TP Removal of Over spray Due to BMPs ................................................. 43 Table 7 Highlands Subdivision Existing Pond Residence Time Calculations .................... 49 Table 8 Highlands Subdivision Proposed Pond Residence Time Calculations .................. 51 Table 9 Highlands Subdivision Proposed Improvements TP Load Reduction Estimates ......................................................................................................................... 52 Table 10 Buttonwood Avenue Proposed Stormwater Facility Residence Time Calculations .................................................................................................................... 55 Table 11 Buttonwood Avenue Proposed Improvements TP Load Reduction Estimates ...... 56 Table 12 Hacienda Village Proposed Wet Detention Pond Residence Time Calculations .... 57 Table 13 Hacienda Village Proposed Improvements TP Load Reduction Estimates .......... 58 Table 14 Pollutant Removal Effectiveness for Stormwater Wetlands .................................... 62 Table 15 N. Orlando Ranches/Winding Hollow Proposed Improvements TP Load Reduction Eshmates ...................................................................................................... 64 Table 16 North Orlando Townsite Proposed Improvements TP Load Reduction Estimates ......................................................................................................................... 66 Table 17 Tuscawilla Country Club Proposed Water Features Residence Time Calculations .................................................................................................................... 69 Table 18 Tuscawilla Country Club Proposed Improvements TP Load Reduction Estimates ......................................................................................................................... 70 Table 19 Winter Springs Boulevard Existing Pond Residence Time Calculations ............... 73 Table 20 Winter Springs Boulevard Proposed Pond Residence Time Calculations ............. 74 Table 21 Winter Springs Boulevard Proposed Pond Improvements TP Load Reduction Eshmates ...................................................................................................... 75 Table 22 Winter Springs and Wedgewood Subdivisions Proposed Improvements TP Load Reduction Estimates ...................................................................................... 77 Table 23 Winter Springs and Wedgewood Subdivisions Proposed Improvements TP Load Reduction Estimates ...................................................................................... 79 Table 24 LID Development Principles ........................................................................................ 80 Table 25 Summary of Estimated TP Removal ........................................................................... 85 Table 26 Estimated Capital Improvement Costs ....................................................................... 86 Table 27 Estimated Cost per lb of TP Removal ......................................................................... 87 Table 28 Capital Improvement Projects Prioritization ............................................................. 89 Cr~A iii S:\65898\63938\Report\Letter Report\TOC.docx Table of Contents City of Winter Springs TMDL Master Plan Figures Figure 1 Project Area ....................................................................................................................... 2 Figure 2 Stormwater System Infrastructure ................................................................................ 5 Figure 3 Stormwater Ponds and BMPs ......................................................................................... 6 Figure 4 Field Review Sites ............................................................................................................ 7 Figure 5 Sanitary Sewer and Septic Systems ............................................................................... 9 Figure 6 Reclaimed Water System .............................................................................................. 11 Figure 7 Lake Jesup Planning Unit ............................................................................................. 14 Figure 8 Soldiers Creek Sampling Stations ................................................................................ 19 Figure 9 Soldier Creek TP Concentrations at Ronald Reagan Blvd ....................................... 18 Figure 10 Soldier Creek TP Concentrations at SR 419 ................................................................ 20 Figure 11 Soldier Creek TN Concentrations at SR 419 ............................................................... 20 Figure 12 Soldier Creek TP Concentrations at the Soldiers/Gee Creek Delta ........................ 21 Figure 13 Soldier Creek TN Concentrations at the Soldiers/Gee Creek Delta ....................... 22 Figure 14 Gee Creek Sampling Stations ....................................................................................... 23 Figure 15 TP and TN Concentrations in Lake Kathryn .............................................................. 24 Figure 16 TP Concentrations for Gee Creek at Moss Road ....................................................... 24 Figure 17 TP Concentrations for Gee Creek at SR 419 ............................................................... 25 Figure 18 TN Concentrations for Gee Creek at SR 419 .............................................................. 26 Figure 19 Howell Creek Sampling Stations ................................................................................. 27 Figure 20 TP Concentrations for Howell Creek at Red Bug Lake Road .................................. 28 Figure 21 TP Concentrations for Howell Creek at SR 434 ......................................................... 28 Figure 22 TN Concentrations for Howell Creek at SR 434 ........................................................ 29 Figure 23 TP Concentrations for Howell Creek at Lake Jesup .................................................. 30 Figure 24 TP Concentrations for Bear Gully/Lightwood Knox Canal .................................... 30 Figure 25 Bear Creek Sampling Stations ...................................................................................... 31 Figure 26 TN Concentrations for Bear Gully/Lightwood Knox Canal ................................... 32 Figure 27 TP Concentrations for Bear Creek at Northern Way ................................................ 33 Figure 28 TN Concentrations for Bear Creek at Northern Way ............................................... 33 Figure 29 Subdivisions with Underdrains Adjacent to Waterways ......................................... 36 Figure 30 Tuscawilla Country Club .............................................................................................. 38 Figure 31 Subdivisions with Septic Tanks Adjacent to Waterways ......................................... 39 Figure 32 Areas Served by Reclaimed Water .............................................................................. 41 Figure 33 Subdivisions with Reclaimed Water Adjacent to Waterways ................................. 44 Figure 34 BMP Comparison ........................................................................................................... 46 Figure 35 Highlands Subdivision Proposed Improvements ..................................................... 48 Figure 36 Buttonwood Avenue Proposed Stormwater Pond and Related Improvements..... 54 Figure 37 Hacienda Village Proposed Improvements ............................................................... 59 Cr~A iv S:\65898\63938\Report\Letter Report\TOC.docx Table of Contents City of Winter Springs TMDL Master Plan Figure 38 Figure 39 Figure 40 Figure 41 Figure 42 Figure 43 Figure 44 N. Orlando Ranches/Winding Hollow Subdivision Proposed Improvements.. North Orlando Townsite Subdivision Proposed Improvements ........................ Tuscawilla Country Club Proposed Improvements ............................................. Winter Springs Blvd. Proposed Improvements ..................................................... Winter Springs/Wedgewood Subdivisions Proposed Improvements .............. Oak Forest Subdivision Proposed Improvements ................................................ N. Orlando Ranches/Winding Hollow Subdivision Proposed Improvements Tributary Area ............................................................................................................ 61 65 67 71 76 78 ~~ 91 v S:\65898\63938\Report\Letter Report\TOC.docx City of Winter Springs, Florida Total Maacimum Daily Load (TMDL) Master Plan Letter Report (March, 2009) 1.0 Background The Florida Department of Environmental Protection (FDEP) adopted a Total Maximum Daily Load (TMDL) for Lake Jesup in 2006 which requires reduction of nutrient loading sources for total phosphorous (TP) and total nitrogen (TN) by 34 and 50 percent, respectively, to meet water quality standards within the Lake Jesup Basin. The Lake Jesup Basin Stakeholders are currently preparing a Basin Management Action Plan (BMAP) to identify activities to reduce the amount of nutrients contained within nonpoint sources that ultimately reach the lake. In response to this, the City of Winter Springs (the City) has embarked on a TMDL Master Plan which will evaluate the available pollutant loading reduction strategies, including the implementation of local projects, participation in regional projects, or the expansion of existing pollutant loading reduction activities. The intent of the master plan is to use the best available information from the Basin Management Action Plan (BMAP) and develop the most cost effective strategy for the City to meet its TMDL obligations. Task 1 included review of the City's stormwater management system and related components that could potentially contribute nutrient loads into the City's municipal separate storm sewer system (MS4) (i.e., septic tanks, reclaimed water). Under Task 2, CDM collected and reviewed data related to the TMDL established for Lake Jesup including FDEP's TMDL report, available water quality data, and information obtained through the BMAP process. Tasks 3 and 4 consisted of identifying pollutant load strategies and estimating the associated load reduction. The City of Winter Springs is a residential community located centrally in Seminole County just to the south of Lake Jesup as shown in Figure 1. The City has an estimated 34,621 residents and 13,533 households. The City's jurisdictional area is approximately 14 square miles and is located entirely within the Lake Jesup Planning Unit. 2.0 City stormwater System Review CDM collected and reviewed data for the City's stormwater management system and related components to develop an understanding of the study area as well as to assist with drawing conclusions regarding potential sources of nutrient loadings within the study area. Data sources included geographic information system (GIs) coverages of the stormwater system infrastructure, existing best management practices (BMPs), sanitary sewer lines, reclaimed water system, and potential septic tank locations. CDM also reviewed the City's stormwater Master Plan, Comprehensive Plan, ~~ S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx N N ,~ ~ N ~ ~ } 0 ~ 'o ~ - 2' O W Z fA p ~ ~ Q ~ m W E vl 2' m ~ ~ w (6 N p N W C7 (n ~ ~ ~ fC ~ Y Z (n ~ z fir' ~ fir' o °~ W p LL 0 ~ o 0 N 0 ~i~lii~ 11p P.~ A ~ ~ ~ -. ~~~~ _~ ~ ~ ~ ~ ~ L L - 1 ` ~~6 e ~' ' ~ ~cc ~ G r! p J .aar U ~ T (~ 7 Q ~ U LL ~ O City of Winter Springs TMDL Master Plan Code of Ordinances, and National Pollutant Discharge Elimination System (NPDES) annual reports. Additionally, CDM performed a field review of the study area to gain a better understanding of its characteristics. Amore detailed description of the review and an evaluation of these data sources are provided below. 2.1 Stormwater Master Plan The Stormwater Master Plan for the City of Winter Springs, adopted in October 1993 (Master Plan), was prepared by Conklin, Porter & Holmes Engineers, Inc. and Gee and Jenson Engineers-Architects-Planners, Inc. The primary objectives of the study were to identify and establish a plan to rectify deficiencies in the stormwater infrastructure, project future stormwater facility needs, develop a capital improvement plan, and investigate funding alternatives. Results of the Master Plan included a 1-, 5- and 10-year major capital improvement plan, a 10-year heavy maintenance improvement plan, minor renewal/replacement improvements, stormwater drainage basin deficiencies recommended for additional study, recommended revisions to the Comprehensive Plan, funding requirements and suggested cost control and record keeping measures. Additionally, a watershed management plan for the Howell Creek Basin, one of the three primary drainage basins within Winter Springs, is currently being prepared by CDM for the St. Johns River Water Management District (SJRWMD) and local jurisdictions. The plan includes three phases and, to date, Phase I-System Inventory and Phase II-Engineering Analysis have been completed, while, Phase III-Alternatives is currently in progress. Phase I of the plan established problem areas in the basin. Identified problem areas located within Winter Springs include: ^ Flooding at Tuscawilla Country Club (predicted Level of Service D for 25-year/24- hour event); ^ Flooding in the Bear Creek Basin (bridges and culverts would be overtopped during major flood events); ^ Flooding at Winter Springs Blvd. (Bear Creek staged up and flooded the road near the approach to the bridge during 2004 hurricanes); and ^ Flooding at the Oviedo Marketplace/Tuskawilla Subdivision (concern over mall ponds staging up too high adjacent to residential backyards). 2.2 Stormwater System Infrastructure Inventory CDM obtained stormwater system infrastructure data from Southeastern Surveying & Mapping Corp. (SSMC). The data were provided in a geodatabase which included locations, structural details, and maintenance information for culverts, open channels, underdrains, stormwater ponds, cleanout locations and other stormwater structures. Culverts were identified in the geodatabase as concrete box culverts, cross drains, ~~ S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of Winter Springs TMDL Master Plan French drains, side drains, storm sewers, unreported facilities and unknown. Other stormwater structures were classified in the geodatabase as box culverts, control structures, curb inlets, ditch bottom inlets, ditch bottom inlet with weirs, drawdowns, flared ends, grate top inlets, headwalls, manholes, mitered ends, pipe ends, tees, and other devices. A map of the stormwater infrastructure showing the culverts, open channel, underdrains and stormwater ponds is illustrated in Figure 2. 2.2.1 Existing Best Management Practices (BMPs) within the City stormwater ponds were included the geodatabase provided by SSMC. The stormwater ponds were identified as wet or dry based on information in the geodatabase and additional input provided by the City. Figure 3 shows the locations of wet and dry detention ponds within the City. Additionally, Figure 3 identifies the areas that are currently treated with stormwater BMPs, including wet detention ponds, dry retention basins and swales. Approximately 3,187 acres of land are currently treated with wet detention ponds, 417 acres are treated with dry retention basins, 702 acres are treated by both wet and dry retention ponds, and 513 acres are treated by swales. 2.2.2 Field Review On March 27, 2008, CDM conducted a field review with the City to gain additional information on the stormwater system components with a focus on potential areas for project implementation. The majority of the sites visited are shown on Figure 4. Some of the primary observations from the field review as well as input from the City are detailed below: ^ Based on the City's input, the Winter Springs High School stormwater retention pond is not large enough. The "Orange Avenue Discharge" site, see Figure 4, is an outfall ditch that discharges treated stormwater and groundwater to Lake Jesup, Photo 1. In Photo 1: Discharge Point to Lake Jesun this area most of the homes are not connected to the City's sanitary sewer system and are using septic tanks. ~~ 4 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx ~;a -,, -- _ ~,~ Z W W J _~ N ~ C ~ a 'i ~ ~ _ ~ ~ ~ rTl l ~-+ ~ U ~ ~ ~ ~ ~ ~ O 0 ~ ~ ~ ~ Q O m w ~ ~ O /~ Q O ~ ~ N i N .~ Q i ~ ' ~ ~ Y z Q ~ Q ~ ~ U ~ cn n n v W U ~~~~ ~ ~ O ~ Z O N C 'i C Q ~ ~a L L y~+ y~+ ~ N O J _~~ V ~ N G1 L L y~+ 7 v ~ 7 LL N L d N 3 O N M tl1 ~, a L ~ m ~_ 0 a L d y+ 3 L 0 y+ • ~ ~ ~ ~ ~~ rn~ .~ i City of Winter Springs TMDL Master Plan The stormwater et detention pond located on Winter Springs Blvd. adjacent to the Bear Creek crossing experiences significant vegetation problems and constant groundwater discharge and is effectively discharging directly into Bear Creek with minimal detention time, see Photo 2. ^ The Tuscawilla Country Club parking lot currently produces a significant amount of discharge to Howell Creek. ^ The area along Arabian Ave. is predominately treated by swales, with limited retention and direct discharge to Howell Creek. ~^ ^ At Howell Creek and Dyson Drive, an (County maintained) outfall to the creek was freely discharging steady flow which may be coming from underdrains. ^ There is an artesian well located in the Parkstone development which discharges directly into Lake Jesup. ^ The bioretention site located in the Highlands development is an area where improvements could be made to increase treatment. 2.3 Sanitary Sewer and Septic Tank Data The City's Utility Department is responsible for the operations and maintenance of the sanitary sewer system. The City operates two wastewater treatment plants and the existing wastewater collection system currently services approximately 90% of the City's households. The locations of the sanitary sewer lines are shown on Figure 5. It is expected that areas currently not served by sanitary sewer are served by septic tanks. Septic tank systems typically have a limited useful life expectancy and failures are known to occur, causing localized water quality impacts. Therefore, areas served by septic tanks within the study area were estimated and are shown on Figure 5, an estimated 789 parcels are served be septic tanks. In the Lake Jesup TMDL Report, FDEP considered impacts of septic tanks within 75 feet of receiving waters that discharge to Lake Jesup. Using this same principle, CDM estimated that there are approximately 231 parcels (29.3 percent) with septic tanks within the City that are within this 75 foot buffer to receiving waters. ~~ ~ f F ~ ~ 5 V ~ 1~ • /~ ~ ~~. ^. ~, ~- .. _ _ { S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx Photo 2: Stormwater Wet Detention Pond on Winter Springs Blvd. z w W J U N ~ ~ ~ ~, J ~ ~ ~ ~ ~ ~ ~ 3 ~ _ °~ D ~ 0 a~i ~ o O °- Q ~ m cn ~ ~, ~' ~ m ~ ~ ~ w ~ ~° ~ ~ a~ w C~ cn ~ ~~ ~ ~ ~~ a ~ Y z Q Q cn in in ~ 'v w ~ Q ° U ~ Z W z N C 'i C Q ~ ~a L L y~+ y~+ ~ N O J _~~ V ~ _N ti O O N O O ~ N L ~~ a~ ~ ~~ V Q d N 3 d N C N City of Winter Springs TMDL Master Plan 2.4 Reclaimed Water System The City utilizes a reclaimed water system in an effort to reduce the quantity of potable water used for irrigation. The system consists of two treatment facilities located at the City's wastewater treatment plants and distribution lines. Locations of these distribution lines were obtained from SSMC and are shown on Figure 6. A more detailed discussion of water quality related to reclaimed water is provided later in this document. 2.5 NPDES MS4 Permit The City is regulated under the National Pollutant Discharge Elimination System (NPDES) Phase I program. The City is part of a large municipal separate storm sewer system (MS4). The City along with its co-permittees (City of Altamonte Springs, City of Casselberry, City of Lake Mary, City of Longwood, City of Oviedo, City of Sanford, FDOT District 5 and Seminole County), was issued a Phase I NPDES MS4 Permit (Permit No. FLS000038) on October 1, 1998. The City's permit was subsequently renewed and was reissued on May 27, 2004. This is a 5-year permit that will expire in 2009. Prior to this date, the City will go through the renewal process. This NPDES MS4 permit authorizes the City to discharge from existing or new stormwater point sources to waters of the state from those portions of the MS4 that are owned or operated by the permittee. Under the permit, the City is required to implement the stormwater management program (SWMP) specified in the permit in order to achieve compliance. Elements of the SWMP include: ^ Maintenance and inspection of structural controls and stormwater collection systems operation; ^ Adherence to County and SJRWMD requirements for areas of new development and significant redevelopment; ^ Roadway litter control and street sweeping; ^ Maintenance of a list of stormwater capital improvement projects (CIPs) and reporting on project status; ^ Inspection of municipal waste TSD facilities not covered by an NPDES permit; ^ Training and certification of pesticide and herbicide applicators as well as public outreach and education on the proper use of pesticides, herbicides and fertilizers; ^ Illicit discharge detection and elimination, spill prevention and response, public reporting, proper disposal of household hazardous waste and limitation of sanitary sewer seepage; ^ High risk industrial facility inspection and monitoring; and, ~~ 10 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx ~ ~ L yam., ~ N a> >+ ~~ L d y+ d .~ V Nd 1.6 • City of Winter Springs TMDL Master Plan Construction site runoff permitting, inspections, enforcements and operator training. Once the BMAP is adopted, the City will also have additional requirements to reduce pollutant loads to Lake Jesup. 2.6 Comprehensive Plan and Code of Ordinances This section summarizes the City's current policies as they relate to stormwater management. CDM reviewed the City's Comprehensive Plan and Code of Ordinances in order to provide a summary of stormwater policies. The City's Comprehensive Plan recognizes stormwater runoff as an issue of local concern. The Comprehensive Plan consists of nine elements which include Future Land Use, Transportation, Housing, Infrastructure, Conservation, Recreation and Open Space, Intergovernmental Coordination, Capital Improvements, and Public School Facilities. Several of the elements include policies related to stormwater management which are summarized below. The Future Land Use Element of the Comprehensive Plan states that new development must be incompliance with the City's stormwater Master Plan and Code of Ordinances. It states that development within the floodplain is allowed, but requires the construction of compensating storage areas to offset any impacts to the floodplain. The Drainage Sub-element of the Infrastructure Element of the Comprehensive Plan provides an analysis of stormwater management for the City in order to establish goals, objectives, and policies that will allow the City to meet drainage and stormwater management needs. This element states that stormwater management is imperative in maintaining water quality of the City's water bodies and specifies that drainage facilities should serve other key functions such as water quality management and aquifer recharge. Based on this analysis, several policies related to stormwater management are adopted in the Infrastructure element of the Comprehensive Plan. These policies institute water quality and quantity level of service standards, mandatory maintenance and utilization of the stormwater Master Plan, restricted development within the 100-year floodplain, protection of natural resources and the existing municipal stormwater network from development and construction impacts, and intergovernmental coordination addressing stormwater issues when applicable. Additionally the Conservation, Intergovernmental Coordination, and Capital Improvement Elements of the Comprehensive plan address stormwater management and establishes related policies that are consistent with those previously mentioned in other elements, as well as, the City's stormwater Management Plan and the City's Code of Ordinances. ~~ 12 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of Winter Springs TMDL Master Plan The following summarizes sections of the City's Code of Ordinances that directly pertain to stormwater management: Chapter 8 of the Code of Ordinances pertains to flood damage protection. Section 8- 32 establishes that "proposed development does not adversely affect the flood- carryingcapacity and/or flood storage capacity of the areas of special flood hazard." Adversely affect is defined as filling in the floodplain without providing compensating flood-carrying and flood-storage capacities. ^ For areas where small streams exist but where no base flood data or floodways have been provided, Section 8-54 establishes that no encroachments shall be within a distance of five times the width of the stream at the top of bank or twenty feet, whichever is greater, from the stream bank. ^ Section 9-241 specifies the current requirements for stormwater management for development. It states that the design for drainage systems in proposed developments must be approved by the city engineer and that all drainage facilities be designed for the 25-year, 24-hour storm. ^ Section 9-242 specifies the additional requirements for drainage facilities for development including: roadside swales, open channels, outfall ditches, street subdrains, underdrains, and underground drainage systems. ^ Sections 19-163 through 19-167 pertain to stormwater funding which is further detailed in the following stormwater Funding Sources section of this memorandum. ^ Sections 19-170 through 19-175 of the City's Code of Ordinances addresses discharges into the municipal storm sewer system, including, allowable non- stormwater discharges, stormwater discharges from industrial, commercial and construction activities, control of pollutant contributions from interconnected MS4s, inspection and maintenance requirements for MS4s, and enforcement of these policies. 2.7 stormwater Funding Sources Section 19-163 of the Code of Ordinances creates a stormwater management utility fee for stormwater services and facilities. This fee is imposed on all developed property within the city. Section 19-164 establishes that the scheduling of the stormwater management utility fee is regulated by the City Commission and sets up rules for calculating the fee based on equivalent residential units (ERU). The current stormwater fee is $5.50 per month per ERU. Sections 19-165 and 19-166 establish additional regulations with respect to the stormwater management utility fee billing, enforcement and adjustment. Additionally Section 19-167 institutes a stormwater management utility fund for deposit of the stormwater management utility fees of which will be used for stormwater management operating needs and capital projects. ~~ 13 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of Winter Springs TMDL Master Plan 3.0 TMDL Data Collection and Review In 2006, FDEP prepared a report that presented the TMDL for nutrients and unionized ammonia for Lake Jesup. The lake was verified as impaired for nutrients and unionized ammonia (NH3) due to elevated annual average Trophic State Index (TSI) values and exceedances of the unionized ammonia criterion (0.02 milligrams per liter [mg/ L] ), and was included on the Verified List of impaired waters for the Middle St. Johns Basin that was adopted by FDEP Secretarial Order on May 27, 2004. The following sections provide some background on the Lake Jesup TMDL itself as well as a summary of existing water quality data. 3.1 TMDL Background Lake Jesup is a shallow lake that has a surface area of approximately 16.7 square miles and has a watershed of approximately 136.5 square miles to the St. Johns River as shown in Figure 7. The majority of surface runoff into the lake is conveyed rF 2 '; _ a ~ ~ y ~"~ 5 - ~:.~ }- , . _ ,~ , ~_~' ~ _ ~ =-_- ~,, Winter Springs - ~ e lR7<ry %~ - ~, ~- ~ - - . ~, \ ~. _. ~n~ . ` ~ - =1~ . . a primarily by three of its main tributaries, Howell Creek, Gee Creek and Figure 7 -Lake Jesup Planning Unit Soldiers Creek, all of which a portion run through the City of Winter Springs. In fact, the entire City of Winter Springs is within the greater Lake Jesup Planning Unit, as shown in Figure 7. Lake Jesup is a Class III water body which means it is designated for recreation, propagation, and maintenance of a healthy, well balanced population of fish and wildlife. The purpose of the TMDL is to restore the water body so that it meets its designated use in the future. The Impaired Waters Rule (62-303, F.A.C.) was used to assess water quality impairments in the Middle St. Johns Basin and specifically the verified impairments for Lake Jesup. The lake was verified as impaired for nutrients based on the fact that during the verified period (January 1, 1996, through June 30, 2003), the annual average trophic state index (TSI) values exceeded 60 every year. According to the Seminole County Watershed Atlas, the long term historic TSI average is 74, which is considered to be eutrophic (i.e., excess nutrients). The impairment for unionized ammonia was based on the fact that 27 out of 154 observations of unionized ammonia exceeded the water quality criterion (0.02 mg/L). ~~ 14 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of lMnter Springs TMDL Master Plan To simulate surface loadings from the Lake Jesup watershed, FDEP delineated the watershed into five subbasins: Gee Creek, Howell Creek, Lake Jesup (the area immediately tributary to Lake Jesup), Little Lake Howell, and Soldiers Creek. Table 1 shows the results of the simulated runoff and respective loadings of TN and TP for each subbasin. As can be seen in the table, the Howell Creek subbasin has the second highest surface runoff contribution. The Soldiers Creek and Gee Creek subbasins combined contribute about 19 percent of the surface runoff. Table 1 City of Winter Springs TMDL Master Plan Percentages of Simulated Runoff and Nutrient Loadings for the Lake Jesup Basin Sub-basin Annual surface runoff %~ Annual TN loading ~%~ Annual TP loading ~%~ Gee Creek 8 8 9 Howell Creek 34 33 41 Lake Jesup 45 47 37 Little Lake Howell 3 2 3 Soldiers Creek 11 10 10 Totals: 100 100 100 In terms of sources of the pollutants in the Lake Jesup watershed, FDEP determined that nutrient input sources are primarily from nonpoint sources and include surface runoff, background TN and TP loadings through baseflow from the surficial aquifer, septic tank TN and TP loadings, artesian input through springs and upward lake bottom leakage from the Floridan Aquifer, atmospheric deposition directly onto the surface of Lake Jesup (including wet and dry deposition), and inflow from the St. Johns River. FDEP concluded that the majority of flow (38 percent), TN (43 percent) and TP (49 percent) loadings is generated through nonpoint source surface runoff for the entire basin. Based on the calculations and the modeling done by FDEP for the TMDL, the following water quality targets were proposed for Lake Jesup: ^ TN -1.27 mg/1 ^ TP - 0.096 mg/1 ^ Chlorophyll-a - 31.2 ug/1 ^ TSI - 65 These target concentrations were then used to determine the overall load reduction needed in the watershed in order to achieve these targets. This load reduction equates to the TMDL. The TMDL is expressed as the sum of all point source loads (wasteload allocations (WLAs)), nonpoint source loads (load allocations (LAs)), and an appropriate margin of safety (MOS), which takes into account any uncertainty concerning the relationship between effluent limitations and water quality: TMDL = EWLAs + ELAs + MOS. ~~ 15 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of Winter Springs TMDL Master Plan The WLA is broken out into separate subcategories for wastewater discharges and stormwater discharges regulated under the NPDES Program: TMDL EWLAswastewater + EWLAsNPDES stormwater + ELAs + MOS. As there are no wastewater point sources that discharge directly into surface waters in the basin, the TMDLs for TN and TP were assigned to the LA and the MS4. The TMDLs for Lake Jesup are expressed in terms of pounds per year (lbs/year) and percent reduction of TN and TP, and represent the maximum long-term annual average TN and TP loadings Lake Jesup can assimilate and still maintain a balanced aquatic flora and fauna. The TMDL for Lake Jesup, formally adopted in 2006, required nutrient loading sources for TP and TN within the Lake Jesup Basin to be reduced by 34 and 50 percent, respectively. Following the adoption of the TMDL, the next step was the implementation of the TMDL or the Basin Management Action Plan (BMAP). The plan is intended to document how TMDL load reductions will be achieved, by whom and in what timeframe. These decisions are to be consensus based agreements among stakeholders. Significant technical analysis, data gathering and outreach efforts are part of the BMAP development. The Lake Jesup, Crane Strand and Long Branch BMAP Working Group was officially formed in May, 2006. Key components of the BMAP will include: ^ Description of loading sources and estimate of loading contributions; ^ Allocations among the affected parties; ^ Load reduction and pollution prevention activities and their estimated load reductions; ^ Implementation schedule, funding, responsibilities and milestones; ^ Monitoring, evaluation and reporting strategy; and ^ Adaptive management measures. To date, BMAP process for Lake Jesup has largely focused on the sources and estimates of associated loadings. This includes identifying potential pollutant sources, continuing data collection and review, completing additional studies, updating land use information and quantifying loading from specific sources. FDEP has recently begun developing draft allocations of pollutants for the individual stakeholders. Based on the most recent BMAP meeting (January 2009), the following draft allocations have been identified for the City of Winter Springs as shown in Table 2. Nitrogen fixation appears to be the significant percentage of nitrogen inputs into Lake Jesup. Therefore, the BMAP process initially focuses on reducing TP which is thought to reduce nitrogen inputs to Lake Jesup. ~~ 16 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of lMnter Springs TMDL Master Plan Table 2 City of Winter Springs TMDL Master Plan Lake Jesup BMAP Surface Runoff Allocation for Total Phosphorus Adjusted Surface Runoff Load (Ibs/yr) 2,274 Septic Load (Ibs/yr) 27 Total Load (Ibs/yr) 2,301 Load Allocation (Ibs/yr) 759 Reduction Required (Ibs/yr) 1,542 Ph I Reduction Required 2009-2014 (Ibs) 513.9 Ph II Reduction Required 2015-2019 (Ibs) 513.9 Ph III Reduction Required 2020-2024 (Ibs) 513.9 Documented BMP Load Reductions (Ibs/yr) 786.4 Load Reduction Remaining for Phase I (Ibs/yr) 0 Load Reduction Remaining for Phase II (Ibs/yr) 241.3 Load Reduction Remaining for Phase III (Ibs/yr) 513.9 As can be seen in Table 2, the percent reduction required is much greater (approximately 68 percent) than the origina134 percent reduction originally specified in the FDEP TMDL report. During the BMAP Stakeholder process, several decisions were made regarding specific loading sources originally identified in the TMDL report including loading from the St. Johns River, baseflow contributions and atmospheric deposition. As these were deemed uncontrollable by the Stakeholders, this shifted the allocation of percent reductions amongst the various loads (including nonpoint sources) in order to still achieve the TMDL. 3.2 Water Quality Data Review CDM downloaded available water quality data for the three major tributaries that run through the City and ultimately discharge to Lake Jesup. These include Soldiers, Gee, Howell and Sweetwater Creek. According to the Lake Jesup Interagency Restoration Strategy (2008), nitrogen fixation appears to be a significant source of nitrogen to the lake. As nitrogen typically occurs in freshwater environments with high phosphorus concentrations, the primary focus of the nutrient load reduction into Lake Jesup will initially be phosphorus. Therefore, for the purposes of this memorandum, water quality data review focused primarily on TP in the tributaries that run through City limits; however, TN data were summarized where available. CDM reviewed available water quality data for individual stations along the major tributaries to determine if there are any noticeable changes in nutrient levels occurring throughout the stream. CDM also reviewed data upstream of the City limits to determine the nutrient concentrations in each stream prior to entering the City. ~~ 17 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of Winter Springs TMDL Master Plan 3.2.1 Soldiers Creek A very small portion of the City (9 percent) is within the Soldiers Creek Basin, approximately 884 acres. The creek itself enters the City's limits near the SR 419 crossing before discharging into the western part of Lake Jesup. Just upstream of the City limits, there were limited water quality data for TP available at station 20010230 (Ronald Reagan Blvd., shown on Figure 8) and the results are shown on Figure 9. Only one data point for TN was available at this station and was therefore not graphed. The next downstream station with available water quality data occurs at SR 419 (as shown on Figure 8). A number of stations were identified at this crossing and the available water quality data for TP are shown in Figure 10. These stations included T- 10, 20010184 and SOL and the average TP concentration for all three stations is 135 ug/1, which is well above the Lake Jesup target concentration of 96 ug/1. The average TN concentration for these same stations is 2.7 mg/1, which also exceeds the target concentration for TN for Lake Jesup (1.27 mg/1). The TN data for this location are provided on Figure 11. The locations of the sampling stations are shown on Figure 8. zoo 180 160 140 120 at ~, 100 a 80 60 40 20 0 4/19/2001 ~~ 9/1/2002 1/14/2004 5/28/2005 10/10/2006 2/22/2008 Date Figure 9- Soldier Creek TP Concentrations at Ronald Reagan Blvd. 18 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx N N ~L C ~ Q ~ N O Z ~ Q Z ~ ~ Q ~ N O ~- Q U ~ ~ ~ N W LL ~ ~ ~ W ~ C7 C1 N U m ~ ~ ~ W Q' z ~ o ¢ U c~ c~ ~ o ~ cn ~ ~ ~, W c~ ~ w (n J J J J J J J J J J ~ ~ ~ ~ Y Z ~ `p ~ U Il LL LL LL LL W W LL LL LL ~ _ Q O Q ~~ W = V N N N N N N N N N N (n (n 'V Ll.I ~ J J U ~ J 4. C ' ~ Q O O O • • • • • • • ~ Z ~ ~ ~li~ C •Q cn a L L ~_C C O J T ~ ~--~ UH m O N O LL W z ~ ~ o °o 3 a ~ ~ m ~ L O ~ ~ ~_ ''J„nn~ vJ C Y N N U L ll~^ V/ a City of Winter Springs TMDL Master Plan a F • • , «• • • • • • T-10 • 14~ • • • •• • • • Avg. TP conc. r±20010184 SOL • • • ~ •: • •~ (134.5 ug/l) • • • • • • •• •• • • • • Lake Jesup Target (96 ug/l) • • • •• • • 0~` 0~ 0~ 06 06 0~ 0~ 0$ 0$ 00 00 00 O~ O~ Off' Off' 03 03 Off` Off` O~ O~ 06 O~ O~ O$ boo Sao o)°~ ~o~ QoA ~a~ 5oQ QQ~ ~o~ ~a~ Ooo boo Sao $)°~ ~o~ 5oQ ~a~ Oo~ QQ~ ~o~ ~a~ Qoo ti~J\ Sao QoA ~o~ ^~ p^' `L ph r~"~ ,~^' ~'1' r~~ O^ ~p OCR ry"~ p0' `L ,~"~ O^' ~O pC~ ry"~ Oct' ~0 r~R' O ri`b' OC9 rlti Date Figure 10 -Soldier Creek TP Concentrations at SR 419 6 5 4 at E z 3 2 1 0 Off` OO OO OrO OrO O~ O~ OO OO Oo' Oo' 00 O^ O^ 00' 00' 00 00 Off` Off` 00 00 OrO O~ O~ 00 ~~o Sao ~° ~a~ P~0 ~a~ ~aQ PQ~ ~o° ~a~ Qa° boo Sao ~° ~a~ ~aQ ~a~ Oo'~ PQ~ ~o~ ~a~ Oao ~° Sao P~0 ~a~ ^h Off' r10 py ti~ ^'`' ti~ ~~ 0,~~ r10 Oro rl"j pot `L0 ^"j O^' r10 Or° rl"j Og' r10 ^D~ Off' ~~ Oro rl`1% Date Figure 11 -Soldier Creek TN Concentrations at SR 419 • • • •• ••• • • • T-10 • • •• •• • ~ 20010184 ~i • ~ •• • •• • ~ SOL ••• • • • • • • vg. conc. mg • Lake Jesup Target (1.27 mg/l) 20 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of Winter Springs TMDL Master Plan 450 400 350 300 250 rn a ~ 200 150 100 50 The next downstream station is station T-8 (as shown on Figure 8), the Soldier/Gee Creek delta, located just west of Lake Jesup. Although results from this station can be influenced by the incoming water quality of Gee Creek, the large majority of samples exceeded the 96 ug/1 target for Lake Jesup for the entire period of record as shown in Figure 12. The resulting average TP concentration for the period of record shown is 128.3 ug/1. TN data were also available at this station (shown in Figure 13) and the average concentration is 1.7 mg/1, which also exceeds the TN target for Lake Jesup (1.27 mg/1). •f •• • •Z • •• •• • • • • • • • • (128.3 i • •• t • • • •• • •~• •• • •~•• • • • • • • • • • •• 1 ~ • • • • • M • • Tar • • • • •• 0P 0y 0~ 00 0°j O^ o`y oP Oy o`O o0 )~c ~~'~ ~a~ ~~~ oea PQt eQ )ac a~ ~a'` ~e~ ~y ry0 ,~~.~ ryP OHO '.°I O^~ r~P ryQ,~ ,~O' ryry Date Figure 12 -Soldier Creek TP Concentrations at the Soldiers/Gee Creek Delta ~~ "conc. ug/q e Jesup get (96 21 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of Winter Springs TMDL Master Plan 3.5 3.25 3 2.75 2.5 2.25 2 ~ 1.75 1.5 1.25 0.75 0.5 0.25 0 o~ ~~~ ^~ • • • • • • • • • •• • • • • • ~ •• • • • • ~ • • • • N • • •• ` • • • : •• • •• • + t Avg. TN conc. (1.74 mg/I) • • • • • Lake Jesup Target (1.27 mg/I) •M • 05 0~ o0 00 0^ oti o°` 05 06 00 00 L`' at ~~ au Qc etr ac a1 L`' e'p ~~ 0 o ti ti Date Figure 13 -Soldier Creek TN Concentrations at the Soldiers/Gee Creek Delta ~~ 3.2.2 Gee Creek Gee Creek runs through the southwestern portion of the City and has an approximate 2,464 acre tributary area in the City (26 percent of the City). The closest station upstream of the City limits with the most comprehensive data set was for Lake Kathryn (as shown in Figure 14). Several stations were identified in Gee Creek just upstream of the City limits; however, these data were collected during the 1970s which revealed extremely high levels of TP most likely associated with wastewater treatment plant discharges at the time. Therefore those data were not considered in this analysis. The TP and TN concentrations for Lake Kathryn are provided in Figure 15. As can be seen from the figure, TP concentrations in Lake Kathryn have consistently remained below 60 ug/1 with a few exceptions, which is substantially below the target concentration of 96 ug/1 for Lake Jesup. TN concentrations have also consistently remained below 0.8 mg/1, which is also below the target concentration of 1.27 mg/1 for the lake. The next downstream station with available data (TP only) is 20012053 located at Gee Creek and Moss Road (as shown on Figure 14). Only six data points for TP concentration were available for this site and ranged from 61 to 280 ug/1, as shown in Figure 16. 22 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx ar -- N ~L O ~ C ~ N ~ W o ~ O 2 ~ ~ ~ ~ ~ ~ p ~5 0 ~ ~ ~ m ~ W~ ~ ~ U C7 C7 Y © r,~ cn ~ ~ ,~ w ~ ~ J J J J J J J J J N R1 d) ~ 2 W ~ ~ u_ r ~ ~ u. ~ cL ~. ~ 77~ m v ~ ~ x ~ ~ •~ _J = ~ N N N N N N N C+.! f*J N 7 fI) UJ '~ W ~ ~ J L] T2 .a = ~ f a G Q D i i i i i i i ~~ i ^ w'~ ~ ,,, ~-- ~ ~~,~ ~'< ~ .° ~~ *S.U l4 _~i~ i k,k 1 i r Y ,nnni ,.~. ~ `` *~~yl ti L_ s.' 1 w ~ •Ia ;t ~ ~ ~ k r ~ _ ~~bV~ /s~.. ;-t •.~ ~5v9, s. fZ~~~*,, s,: ,x~- uw.tC'~Y... r'~ ~n ..Fi :k~e Y ` ... t q 3 g 1~` \ ~`~"~• `~. I d r ~ '~ti 15 l .. S } ~ ' III+~_~_~ d _. _._-_ -I r_s.. ~°~t~- ~_~ U3 C17 L ~_ 0 ~, U ~ s ` r~ c City of Winter Springs TMDL Master Plan 120 100 80 rn V 60 a 40 20 0 • • ~ • • • ~ • ~~ ~ ~i ~ • ~ ~~ • • • • • • ~ Z • ~ ~ ~° m° mti m~ ~` m6 m~ m° o° o° o~ o°` oy o~ o° o° o° oti o°` o~' 06 ryy~a~ o6oG~ ^~~e~ o~,~\ '~~`~o,, ti~'~a`,'~^P~o; `L~OeG o~~a~ '~~'~ee `~^,ac '`~',~c ti~oG~ ~^~a 0'~,~\ o`OOeG '`~'Pe` o^~ee '`~,ac ti~~a~ '` oG~ Date Figure 15 - TP and TN Concentrations in Lake Kathryn rn a 1.2 1 •TP ^TN 0.8 rn 0.6 ~ Z 0.4 0.2 0 300 275 ~ 250 225 200 175 150 125 ~ • • Lake Jesup Target (96 ug/I) 100 75 50 25 0 O^ 00' 00' 00 Off` Off` O~ O~ 00 00 O~ O~ ~o~ ~a~ oed ~o~ ~a~ o°~ e~ eQ a o~~ PQ~ ~o~, o~' tip` '.° ti~ ^°` o'`P ^~~ o~~ ti°`~ '~~ ti~ '.°` Date Figure 16 - TP Concentrations for Gee Creek at Moss Road ~~ 24 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of Winter Springs TMDL Master Plan 350 300 250 200 rn a 150 100 50 Further downstream where Gee Creek crosses SR419, three stations (as shown in Figure 14) had available data for TN and TP concentrations. These included stations 20010185, T-9 and GEE. TP concentrations are shown in Figure 17 while TN concentrations for stations 20010185 and GEE are shown in Figure 18. In more recent years, the measured TP concentrations have been consistently above the Lake Jesup's target concentration of 96 ug/1, whereas the majority of TN sampling results have remained below the lake's target concentration of 1.27 mg/1. The long term average TP and TN concentrations at this location are 114 ug/1 and 1.14 mg/1, respectively. ^ • • T-9 .. - ~i GEE • • v • 20010185 • • • • • ~~ ~ i ~ • ^ • • { ~ • ••j0- • • • Avg. TP conc. (114 ug/I M • • • N ~• ~ ~ • • ~- • ;~~ • Lake Jesup Target (96 ug/I) • •• • :• • • •••M M • •~ • • • M • • • • O~ O~ O~ 00 00 O~ O~ 00 00 00 00 00 O^ O^ 00' 00' 00 00 Off` Off` O~ O~ 00 O~ O~ 00 o~ a~ ~o~ e'd o°~ a eQ Q~ o~" a~ e~ o~ a~ ~o~ e'd eQ a~ oL` PQ~ ~o~" ~a~ oeU ~o~ ~a~ Poop ~e'° ^~~ o^~ ti~ o~F ~~P ,~^`5~~~' ^hPo~.`, ~cr`S o~~ ~~~ o~~ ti~ ,~~~ o~.`' ~cr`S o~ ~~ o~; ~q; ,nor o`~ ,~ei o~ ~~; Date Figure 17 - TP Concentrations for Gee Creek at SR 419 ~~ 25 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of Winter Springs TMDL Master Plan 3.5 3 2.5 rn E 2 Z 1.5 1 0.5 • 20010185 GEE Lake Jesup Target (1.27 mg/I) • Avg. TN conc. (1.14 mgr g'l g`b 00 O^ 03 OR Oh O'l O~ 00 O'~ O`L OR Oh 00 O`b O°' ^^P~~ ~~Oed o~~a~ ^~~ee, ~^~m~ ^`'~~~ ~~G~ ^'`~m~~ ~~~~ p6Oe~ ^°'PQ~~ O'`~eQ ^~~m~ ~~~m~ ^oG~ ~~~e~~ 06~~~ Date Figure 18 - TN Concentrations for Gee Creek at SR 419 ~~ The next station downstream is at station T-8, the Soldier/Gee Creek delta, just west of Lake Jesup. This is the last station downstream before the creek discharges into the lake. The results for this station were previously shown in Figures 12 and 13. The resulting average TP concentration for the period of record shown is 128.3 ug/1 while the average TN concentration is 1.7 mg/1 at this location. 3.2.3 Howell Creek Howell Creek runs through the central portion of the City and has an approximate 3,750 acre tributary area in the City. Bear Creek, a tributary to Howell Creek, also runs through a portion of the City and converges with Howell Creek just north of Winter Springs Boulevard. Just upstream of the City, there were some water quality data available at Red Bug Lake Road. Stations HCRB, 20010189 and HCRS had limited data available for TP and their locations are shown in Figure 19. The sampling results for this station are provided in Figure 20. Measured TP concentrations at this location were all below the TP target for Lake Jesup (96 ug/1). The next downstream station(s) with comprehensive data available does not occur until the crossing of Howell Creek with SR 434 (shown in Figure 19). The average TP concentration at this location is 111 ug/1 while the average TN concentration is 0.99 mg/1 as shown in Figures 21 and 22, respectively. 26 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx r C v rn~ ~ ~ c U a a City of Winter Springs TMDL Master Plan 100 90 80 70 60 at 50 a 40 30 20 10 0 O~ O~ O~ O~ O~ O~ O~ O~ O~ O~ O~ O~ cCac PQc PQc ~a~ ~a~ ~J\ PJ~ PJ~ 5eQ O~ c~°, OeG DoS p`~ ~'D ~'Y r~'~~ ~`l' O~ ,~'~ rlh r10 ^k DoS 500 450 400 350 300 250 a 200 150 100 50 0 'b`b 0~ 0^ 0~ 0~` 0~ 0~ 0$ 00 O^ O`L Off` O~ OrO O$ OeG cCa~ ~eQ lac lac ~~~ ~a~~ a~J\ OeG PQr ~eQ lac cCa~ ~~~' Leo ry'3 0'1 ,~0 ,~~ ,IFS tig ,~~ rl, 0~ ^°~ 0^ ^R ti$ ^0 rl`L Date Figure 21 - TP Concentrations for Howell Creek at SR 434 VY~r~ 28 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx Date Figure 20 - TP Concentrations for Howell Creek at Red Bug Lake Road City of Winter Springs TMDL Master Plan 1.6 1.4 1.2 1 rn ~ 0.8 z 0.6 0.4 0.2 0~ 0~ ~~ 0^ 0~ 0~` 0y ~~ 0~ 0°j o^ Off' Off` Oy o`O O~ o°j PEA oe~ ~a~ ~eQ lac ~~~ O~~ c~a ~~~ oec; ~~, ~eQ lac ~a~ ~~~ ~e~ 6~~\ Date Figure 22 - TN Concentrations for Howell Creek at SR 434 The last station in Howell Creek prior to discharging into Lake Jesup is station T-5 as shown in Figure 19. As shown in Figure 23, the long term average TP concentration in Howell Creek prior to discharging into the lake is 112 ug/1. There were no recent TN data available for this station. 3.2.4 Bear Creek/Lightwood Knox Canal As mentioned previously, Bear Creek is the only major tributary that discharges into Howell Creek within the City limits. Outside of the City limits, Bear Gully Canal and the Lightwood Knox Canal converge near the Oviedo Marketplace to form Bear Creek prior to entering the City. There were limited data associated with identified sampling stations located along this tributary. TP concentrations in both the Bear Gully Canal and Lightwood Knox Canal prior to their confluence near the Oviedo Marketplace are shown in Figure 24. The location of these stations is shown in Figure 25. As can be seen the concentrations at BCRW are significantly lower than those at BCRE, indicating that runoff from the sod farms upstream in Lightwood Knox Canal may be influencing the TP levels. Measured TN concentrations at these same stations are shown in Figure 26. ~~ 29 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of Winter Springs TMDL Master Plan 350 300 250 200 a a 150 100 50 0 • • • • • • • • • • • • • • • • • • • • •• • •• • • ~ i • •••• •• • • • • • s • • • • • • • • • Avg. TP • • • • • •~ •• • • N • • w • • conc. 11 •~ • ~~~m • • • • • w • • • • • • j •1 • • ~• • • ~ • • • • •• j I • • • •• Lake Jesup T t 96 l • • • • • •• • • ~ ~ • ~ • arge ( ug ~ • • ~ • • ~• ~ • i• •• • • • • •• •• i• • S ~ • • • •• • • • • ~ • ~ • o°` oh o1 0o eo P^ oti P°` oh P6 0° o0 o~ O~ at, ~J~ e~ Qt eQ a~ al L`' °'d ~o~ ^y~ ti° ^^~ 'v°` o6a ^~P o^~' ^~~ ti~~ ^oP titi~ o° • T-5 r Date Figure 23 - TP Concentrations for Howell Creek at Lake Jesup 350 300 250 200 a 150 100 50 0 O^O ^,~ J _, • ~ Lake Jesup' (96 ug/I • • ~a o~ o~ o~ o~ o~ o~ o~ o~ 06 ti6 ^~ o~ ti~ ^a Oa tip` Date Figure 24 - TP Concentrations for Bear Gully/Lightwood Knox Canal • BCRVV ^ BCRE arget VY~r~ 30 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx T m c~ m c c~ cn ct3 ~ ~ c~ o ~' ~ n~ ut cn City of Winter Springs TMDL Master Plan E z 2.5 1.5 0.5 ^ BCRE • BCRW Date Figure 26 - TN Concentrations for Bear Gully/Li~htwood Knox Canal ~~ Further downstream, limited data were available where Bear Creek crosses Northern Way as shown in Figure 25. The measured TP and TN concentrations at this location are shown in Figures 27 and 28, respectively. In almost all cases, TP concentrations exceed the Lake Jesup target while TN concentrations remain under the target. 3.2.5 Water Quality Summary Based on the water quality data presented, CDM summarized the results for each major tributary in Table 3. On average, Soldiers and Gee Creek appear to have similar concentrations of TP whereas the measured concentrations in Howell Creek are slightly less. TP concentrations were the highest in Lightwood Knox Canal prior to entering the City limits. TN data were more limited for the tributaries. TN concentrations appeared to be the highest in Soldiers Creek and Lightwood Knox Canal. 32 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx 0 07/17/07 08/06/07 08/26/07 09/15/07 10/05/07 10/25/07 11 /14/07 12/04/07 12/24/07 City of Winter Springs TMDL Master Plan 160 140 120 100 at 80 a 60 40 20 0 0~ 0~ 0$ 0°j O^ O`L Off` O~ OrO O$ O°' c~' a~" o~ e~ Q~ eQ ac a~ c~' eo o~ ti`~o ^^~ ti°`~ o`~~ ^o,P o'`~ ^°`~ ~$cc ^~o titi~ ooh 1.3 1.2 1.1 1 0.9 0.8 at ~ 0.7 z 0.6 0.5 0.4 0.3 0.2 0.1 e`' e~ e$ eo o'` oti o°` o`' 00 0`~ 00 O~ti Sae, ~°v ped QQc geQ lac a~ o~ti ~e.° ~°v Date Figure 28 - TN Concentrations for Bear Creek at Northern Way ~~ 33 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx Date Figure 27 - TP Concentrations for Bear Creek at Northern Way City of Winter Springs TMDL Master Plan Table 3 City of Winter Springs TMDL Master Plan Water Quality Data Summary Average TP Concentration (ug/I) No. Samples Average TN Concentration (mg/I) No. Samples Soldier Creek at Ronald Reagan Blvd. 116.7 6 N/A N/A at SR 419 134.5 168 2.70 105 at Soldiers/Gee Creek Delta 128.3 299 1.74 151 Gee Creek Lake Kathryn 39.3 51 0.70 12 at Moss Road 133.3 6 N/A N/A at SR 419 114.0 166 1.14 37 at Soldiers/Gee Creek Delta 128.3 299 1.74 151 Howell Creek at Red Bug Lake Road 75.0 9 N/A N/A at SR434 111.0 160 0.99 37 at Lake Jesup 112.0 282 N/A N/A Bear Creek Bear Gully Canal 106.8 7 1.15 5 Lightwood Knox Canal 212.3 5 1.51 4 Northern Way 114.3 4 0.90 4 4.0 Pollutant Load Source Identification In order to identify pollutant load reduction strategies that are feasible for the City, it is first necessary to identify the potential sources of pollutants that may be contributing loads to Lake Jesup and its tributaries. A more detailed discussion of each of these potential sources is provided in the following paragraphs. Based on the data collected in Tasks 1 and 2 as well as the field visit conducted in early 2008, CDM identified a number of priority areas that could potentially be discharging a nutrient load to the City's municipal separate storm sewer system (MS4). The priority areas were categorized based on the source of potential pollutants and are as follows: ^ Underdrains ^ Golf Courses ^ Septic Tanks ^ Reclaimed Water ^ Areas without Stormwater Treatment/Stormwater Facilities Requiring Improvements ~~ 34 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of Winter Springs TMDL Master Plan 4.1 Underdrains A number of subdivisions throughout the City are served by underdrains. The SJRWMD defines an underdrain as a drainage system installed beneath a stormwater holding area to improve the infiltration and percolation characteristics of the natural soil when permeability is restricted due to periodic high water table conditions or the presence of layers of fine textured soil below the bottom of the holding area. These systems usually consist of a system of interconnected below-ground conduits such as perforated pipe, which simultaneously limit the water table elevation and intercept, collect, and convey stormwater which has percolated through the soil. During the field visit in March, 2008, CDM observed two instances where dry weather discharge to the MS4 was occurring as a result of underdrains. An example of dry weather discharge, which is actually an outfall from a subdivision within unincorporated Seminole County, is shown in Photo 3. Based on these observations and feedback from the County, underdrains as a source of nutrient loads may be of concern as residential areas are typically irrigated and fertilized (and in many cases these two practices are overused), resulting in Photo 3 -Discharge into Howell Creek at discharge to the local drainage system that Dyson Drive may be laden with nutrients. In a study funded by FDEP, Harper et. al. (1999) observed that filter media in underdrains appear to exhibit poor removal efficiencies for phosphorus species as well as heavy metals. Conversion of trapped particulate matter in the filter media into dissolved forms was observed for several parameters, such as ammonia, nitrate, and orthophosphorus. CDM identified those areas within the City that are served by underdrains and currently do not have stormwater treatment in place (with the exception of the Winding Hollow Subdivision, the City indicated discharge from underdrains is directed towards the existing on-site stormwater best management practices (BMPs)). Using the geographical information systems (GIS) software package Arcview Version 9.2, CDM identified those areas with existing underdrains that do not have stormwater BMPs and are located adjacent to open waterways. These areas, shown in Figure 29, include the following: ~~ 35 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx w w J 3 a a a ° o ~- a ~ i? N N ~ m "n N '~ r ui w w -- C T T T ~+ c 1 2q Z Z ~ r N M q N N n C K ~ ~ ~ r~ m m ~ 7' O 7 7 7 ~ v ~~ ra O O O O ~ ~ ~+ ~ ~ ~ ~+ N N ~ c v V o o [~ o Z Z Z Z Z 0 0 0 4 0 c7 c7 ~ N N y Z Z Z Z~>> 7 7~ a~ a a Z Z' B S c D~~~ ~K w w w~~~ P O O O~~ e # ~w w~ a a a a a o o a~ z z~ z z w~ ,~ € ~ n ~ _ ~ a ~ ~ X x x ~ vOi ° 5 ° ° ° z z a ~ ~ _ -~ ~ ~ ~ a L+. i~ cn C ~ ~ ~ £I~ ~ ~ ~ U] ~]] C ~ O J 7.~ ,,~ ~ U~ d o LL 0 o~ as ~r N ~ ~ ~ as ,_. LL C7 C U ~_ City of Winter Springs TMDL Master Plan ^ Highlands Section 2 (Soldiers Creek) ^ N. Orlando Ranches Sections 2A, 9 & 10 (Gee Creek) ^ N. Orlando Townsite Sections 4th Addition Replat (Gee Creek) ^ Oak Forest Unit 2A, 2B & 3 (Little Lake Howell) ^ Winding Hollow Subdivision (BMPs in place but underdrains connect directly to No-Name Creek) ^ Winter Springs Units 2 & 3 (Howell Creek) 4.2 Golf Courses There are two golf courses located within the City, the Tuscawilla Country Club and the Winter Springs Golf Course. The Winter Springs Golf Course is currently closed and there are currently no plans for its future reopening or development. The Tuscawilla Country Club is privately owned and is situated such that Howell Creek runs through the golf course itself as shown in Figure 30. The golf course is considered a potential source of nutrient loading to the City's MS4 for several reasons: 1) untreated runoff is discharged directly into Howell Creek; 2) there are limited stormwater BMPs on-site to treat stormwater runoff; 3) large quantities of fertilizers are typically applied to golf courses; and 4) the golf course is also irrigated with reclaimed water which has higher nutrient concentrations than potable water. There are several stormwater ponds adjacent to or appear to be located on the golf course; however, these ponds serve the adjacent subdivisions and not the golf course itself. 4.3 Septic Tanks FDEP identified septic tanks as a potential loading source of nutrients to the MS4 in the Lake Jesup TMDL Report (FDEP, 2006). In the Lake Jesup BMAP, FDEP considered impacts of septic tanks within 75 feet of receiving waters that discharge to Lake Jesup. Using this same principle, CDM estimates that there are approximately 231 parcels with septic tanks within the City that are within this 75 foot buffer to receiving waters (i.e., lakes and streams). The subdivisions with septic tanks that are adjacent to water bodies are listed in Table 4 and their locations are shown in Figure 31. ~~ 37 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx y w C Q} y n'~ E 01 V N C i C N ~ y r _ ` ~ ~ U U 9 ~ C) C ~ ~ ~ Q ~ W ~ ~' E v « ~ ~ ~ m ° ~ ~ O ~ a ~ ~+ `~ ~ o ~ LLl y J ~' ~' t o u] ~ ~ ~ o ~ m o C] ~ U m C7 .~ t7 ~ d c~ ~ ~ t7 = ~ ~ ~' ~ ~ CJ e. i1 °~ H a o U d ~ N ~ ~ `m ~ ~ ~ I • `_i D D • D D • D D ® • • # ~ ~ u~ C ~ 4I) d ~ ~ rll D7 C f/1 O J 7.~ .~ ~ ~ =. 1 z e~ ~ CJ _~ +-• [.~ st3 .~ [SS U i!] M ~ 7 ~ ~_ .--~ LL j O C N U CO "~ Q N Y C CO U Q N L .--~ .~ N C O .N .~ 7 City of lMnter Springs TMDL Master Plan Table 4 City of Winter Springs TMDL Master Plan Subdivisions with Septic Tanks in Close Proximity to Water Bodies Subbasin Subdivision Gee Creek Bahama Ranches Maharaj Place Morie Subdivision Moss Road Ranches N. Orlando Ranches Sec 1, 1A, 1B, 2, 2A,3, 4, 6 Oak Hill Estates Seibert Manor Susan Woods Howell Creek Winter Springs Units 2 & 3 Lake Jesup Estes Tuskawilla Mitchells Grant S/D of Lot 54 BLK D Tuscawilla Shores Little Lake Howell Dr. Mosley's Replat Dunmar Estates N. Orlando Ranches Sec 7 Tuscawilla Trail Subdivision Tuscawilla Unit 05 For those areas listed in Table 4, the City may want to consider expanding their wastewater service areas to include these areas. Section 19-28 (required use of public sewers) of the City's Code of Ordinances requires residents to connect to the central sewer if the property is within 50 feet of an available point of connection. As a project that would help towards reducing nutrient loads to Lake Jesup, the City might consider subsidizing the connection fees in order to gain public support for the extension of the central sanitary sewer system. 4.4 Reclaimed Water The City uses a reclaimed water system in an effort to reduce the quantity of potable water used for irrigation. This includes public sites such as the Winter Springs and Tuscawilla golf courses, Sunshine Park, Sam Smith Park, Trotwood Park and Central Winds Park as well as the medians on SR 434, Tuskawilla Road and Winter Springs Blvd. Additionally, there are close to 1,600 homes in the City that are connected to the reclaimed water system. Using the City's reclaimed water, parcel and subdivision GIS layers as well as the known public places receiving reclaimed water, CDM identified the areas with reclaimed water services as shown on Figure 32. The approximate acreage of areas receiving reclaimed water through irrigation is approximately 1,100 acres or about 12 percent of the total City area. ~~ 40 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx cv ~, ~~ a~ ~~ ~. ar su d i City of tMnter Springs TMDL Master Plan There has been some recent speculation that reclaimed water, depending on how it is managed, may be a potential source of nutrient loadings to the MS4. According to a recent presentation given by Dr. Harvey Harper (Irrigation with Recycled Wastewater - Good Intentions Gone Awry? presented at the 2007 Florida Stormwater Association Winter Conference), the chemical characteristics of reuse water are highly variable and depending on the location and level of treatment, reclaimed water may have the potential to significantly impact water quality in surface waters. In the document entitled Guidelines for Water Reuse (USEPA, 2004), a summary of water quality parameters of concern, with respect to their significance in water reuse systems, as well as approximate ranges of each parameter in raw sewage and reclaimed water was provided. In the case of nutrients, the following range of concentrations in reclaimed water is as follows: ^ Nitrogen: c1 mg N - 30 mg N/L ^ Phosphorus: <1 mg P/ L - 20 mg P/ L Recent samples analyzed by the City's wastewater treatment plant lab indicate the average TP concentration in the City's reclaimed water is 4.95 mg/1. A copy of one of the City's Reclaimed Water Effluent Analysis Report (2003) indicated that the nitrate concentration is 11 mg/1 (TN is not sampled for). Using the same principles applied by Dr. Harper, CDM calculated the potential phosphorus loading rate from reuse irrigation as shown in Table 5. Table 5 City of Winter Springs TMDL Master Plan Estimated Nutrient Loading Due to Reclaimed Water Application Total Area Served by Reclaimed (ac) 1,100.0 Total Reclaimed Consumed for Irrigation (MGY) 540.8 Irrigation Rate (MG/week) 10.4 TP concentration in reclaimed water (mg/I) 4.95 Weekly TP load (Ibs/wk) 429.6 Annual TP load (Ibs/yr) 22,341.2 Volume of Reclaimed lost to over spray or runoff -assume 5% loss (MG/week) 0.5 Weekly TP load lost to over spray or runoff (Ibs/week) 21.5 Annual TP load lost to over spray (Ibs/yr) 1,117.1 Once the annual TP load lost to over spray was calculated, it was then necessary to estimate how much of this load may actually enter the City's MS4. Using the City's BMP tributary area (previously shown in Figure 30) and GIS capabilities, CDM calculated the areas served by reclaimed that also have stormwater treatment. This summary is provided below in Table 6. ~~ 42 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of tMnter Springs TMDL Master Plan Table 6 City of Winter Springs TMDL Master Plan Estimated TP Removal of Over spray Due to BMPs Percent of TP Loading from Removal of Over Acres Total Over Spray in Spray TP Loading Reclaimed Reclaimed Service by BMPs (Ibs/yr) Service Area Area w/BMPs Ibs/ r Area served by Reclaimed 28 8 2 6% 29 2 5 8 w/Dry Ponds . . . . Area served by Reclaimed 658 5 59 9% 668 7 401 2 w/Wet Ponds . . . . Area served by Reclaimed 123 1 11 2% 125 0 81 3 w/Wet& Dry Ponds . . . . Area served by Reclaimed 289 6 26 3% N/A N/A w/o BMPs . . Totals: 1,100.0 100.0% 823.0 488.3 It is estimated that BMPs in the reclaimed service areas remove 488.31bs/yr of this potential TP load or 44 percent. This leaves approximately 6291bs/yr that could potentially enter the MS4 due to over spray with reclaimed water. The values shown in the table are the estimated TP loads due to irrigation with reclaimed water. A portion of this will be taken up by plants and adsorbed by soil. The portion lost to over spray and/or runoff is consistent with the assumptions made by Dr. Harvey Harper. Dr. Harper also concluded that reuse water applied to golf courses and landscaped areas at a constant rate throughout the year can create constant discharge which is independent of rainfall. These additional inputs are not usually considered in normal pollutant loading analyses. Therefore, loading impacts from reclaimed water may need to be considered in nutrient budgets and TMDL allocations. Additionally, Dr. Harper showed that loading from reuse irrigation is comparable to loading from fertilization and concluded that fertilizer use may not be necessary when reuse is used for irrigation. As the calculations included all areas served by reclaimed water within the City, CDM identified those areas currently served by reclaimed water, do not have stormwater BMPs in place and are directly adjacent to water bodies. These areas may be considered a higher priority as a portion of the estimated load due to reclaimed water application could more easily enter the MS4 compared to other more isolated areas within the City. These areas are shown in Figure 33 and include the following: ^ Tuscawilla Country Club (Howell Creek) ~~ 43 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of Winter Springs TMDL Master Plan ^ N. Orlando 2nd Addition near Moss Park (Gee Creek) ^ N. Orlando Terrace, Unit 1, Sections 1, 4, & 6 (Gee Creek) ^ Winding Hollow Subdivision (BMPs in place but some underdrains connect directly to No-Name Creek in the Gee Creek Subbasin) Currently, the City does not have along-term plan for improvements to its reclaimed water system that will lower the TP concentration which may result in a potential load reduction to the MS4. 4.5 Street Sweeping As part of the Lake Jesup TMDL BMAP, FDEP developed a methodology to be used by all Stakeholders to calculate the pollutant load removal for TP due to street sweeping. The calculations are based on total miles swept (annually) as well as frequency of sweeping. For the City, FDEP based the calculation on information presented as part of the City's Year 3 NPDES Annual Report. According to the Year 3 NPDES Annual Report, the City swept 570.7 miles of roadway and performed the activity on a quarterly basis. Based on the spreadsheet provided by FDEP, this is equivalent to 7.31bs of TP removed on an annual basis due to street sweeping. 4.6 Areas without Stormwater Treatment/Stormwater Facilities Requiring Improvements Best management practice (BMP) information used to develop the TMDL by FDEP was as current as January 2005, when the TMDL was developed. CDM obtained the BMP coverage developed by PBS&J for the County's NPDES pollutant loading model (and presumably the Lake Jesup TMDL). CDM compared its BMP coverage developed as part of this effort using information from the City's stormwater geodatabase (previously described in this memorandum) to the coverage developed by PBS& J. The two were overlain and are shown in Figure 34 for comparison purposes. As can be seen from the figure, there are some distinct differences between the two layers. The purpose of this comparison was to determine if there were any significant areas served by BMPs not taken into account in the TMDL modeling. With the exception of a few areas (shown in yellow), treatment in the majority of the City was taken into account for the TMDL modeling in addition to other areas not identified by CDM or the City as having treatment (e.g., landlocked areas discharging to natural water bodies). Although many areas within the City currently have stormwater management systems and BMPs in place, there still remain some older areas that were constructed prior to the SJRWMD surface water management requirements. A number of areas were identified where stormwater management could be improved, thus providing treatment to areas where currently none exists or improving the treatment that already exists. Additionally, CDM observed several stormwater facilities could be improved in order to increase existing treatment efficiencies. These areas and recommendations for improvements are discussed in the following section. ~~ 45 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx c ~ 4 ~ ~ 0 U a m i City of Winter Springs TMDL Master Plan 5.0 Recommended Structural Pollutant Load Reduction Strategies The following paragraphs provide recommendations for structural improvements that when implemented, can help the City achieve the goal of reducing nutrient loads from nonpoint source runoff to Lake Jesup. 5.1 Soldiers Creek Subbasin 5.1.1 Highlands Subdivision Pond Enhancement There exists a large wet detention area at the downstream end of a major tributary that runs through the Highlands Subdivision just before discharging to Soldiers Creek as shown on Figure 35. This wet detention area currently acts as an off-line pond and is equipped with a control structure and has an estimated tributary area of approximately 241 acres. During the time of the field visit in March 2008, the control structure for the pond was steadily discharging. Based upon inspection of the pond, improvements could be made to provide additional treatment volume as well as increasing the detention time. Observations indicated the pond may not be achieving optimal removal efficiency for pollutants as the pond was discharging via the control structure during a relatively dry period. As a large portion of the upstream area to the pond already has stormwater treatment in place, improving this pond's performance would create a BMP treatment train effect, thus improving pollutant removal for the entire tributary area. In addition to providing enhanced water quality treatment, the additional storage provided by the pond improvements may also help with flooding issues observed in this area during Tropical Storm Fay in August, 2008. The City indicated that approximately 2 feet of street flooding occurred at Sheoah Circle and Falkirk Drive. This area of the Highlands Section 1 subdivision where the flooding occurred discharges directly to Soldiers Creek without any stormwater treatment. As part of the overall water quality management plan for this area, the City may want to consider re-directing some of this flow to the southeast towards the improved pond for flood control purposes. A detailed hydrologic and hydraulic analysis (not part of this scope of services) of this alternative would be required for designing these modifications. CDM estimated the tributary area to the improved pond using the City's stormwater system inventory as well as USGS 5-foot topographic contour data (there were no 1- foot topographic contour data available for this area of the City). The estimated tributary area that would be treated is approximately 289 acres and is shown in Figure 35. Of those 289 acres, the following is currently treated: 20.5 acres by dry detention; 102 acres by wet detention; and 37.6 acres by a combination of wet & dry detention. Therefore the proposed pond would be providing treatment for untreated areas as well as creating a treatment train effect for those already treated areas. ~~ 47 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx j C O tL U d' ~ ~ m E ~ ~ N v m m m ~ W G c h v G N ~ - v d ~ ~ N ~ m ¢~. m O W ~ a ~ r ~ `_ a ~ _p C ~ y ~ Q '~ C ~ ~ ~S m LJJ ~ m m m t i ~ ~ ~ ~ m o w ~ m -~~, a a ~ ~ r m ~' ~ vQi ~ ''' ~ 0 0 0 ~ v Gyl U ~ ~ r ~ m v a ~ °' W v c o ~ ~ m W y'j a ~ a ~ v j o ~ SYJ = `~° ~ `° air w d L 4 ~. ~ a w n a c ~ a a a N iri i9 C] i] o 0 0 ~ C3 S ~ ~ O ~ ~ fl fl ~ ~ N ~ lF C~ ~ y• c~ ^ a s Q o• o o a w~ I~ ~.' o ~ ~-~ Crs .Q ~ CJ} iL L L D J ~~ ±'' ~ ~~ c~ ~ a~ ~v ~ ~ r.Fr Q C7_ C '~3 e]] VY a 0 .N ,y s3 _~ a City of tMnter Springs TMDL Master Plan Recommendations Based on this conceptual analysis, CDM recommends the following: ^ Obtain water quality samples (grab sample) just upstream of the pond as well as at the discharge in order to determine its current removal capabilities (multiple samples based on storm events will avoid samples containing purely baseflow); ^ Increase the pond area (as well as associated volume) to 3.5 acres (a wetland boundary determination should be made to determine the exact size of the expanded pond area); ^ Analyze the existing control structure to determine the specific improvements needed to achieve in the proposed pond; and ^ Redirect all or a portion of the drainage from the Highlands Section 1 subdivision to the improved pond in order to alleviate flooding in this area. Estimated Load Reduction As mentioned previously, CDM observed that the existing wet pond was continuously discharging during dry-weather which indicated that the pond may not be achieving its design treatment efficiency. FDEP's TMDL pollutant loading model assumes that existing BMPs are providing the assigned treatment efficiency (i.e., 60 percent TP removal for wet detention). Based on this assumption and field conditions, CDM felt that the existing pond is achieving a treatment efficiency that is something less than the 60 percent assigned by the TMDL pollutant loading model. CDM performed calculations, provided in Table 7, to estimate whether the pond is achieving the desired residence time for water quality (and therefore quantity) treatment for the existing tributary area of 241 acres. Table 7 City of Winter Springs TMDL Master Plan Highlands Subdivision Existing Pond Residence Time Calculations Existing Tributary Area to Wet Detention Pond (acres) 241 Total % Impervious 25.8% Runoff Coefficient 0.38 Total Impervious Area (acres) 62.2 Pond Data Pond Sideslope Ratio (Horizontal :Vertical - i.e. 4:1) 4 Bottom of Pond (ft-NGVD) 10.0 Top of Bank (ft-NGVD) 14.0 Pond area at Bottom (acres) 1.2 Pond area at NWL (acres) 1.6 ~~ 49 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of lMnter Springs TMDL Master Plan Table 7 City of Winter Springs TMDL Master Plan Highlands Subdivision Existing Pond Residence Time Calculations Pond area at Weir (acres) 1.6 Pond area at Top of Bank (acres) 1.6 Permanent Pool Volume Calculations Calculation of Permanent Pool Volume required (acre-ft) 31.6 Normal Water Level (ft-NGVD) 14.0 Depth of Permanent Pool Volume (PPV, ft) 4.0 Average Area for PPV (Ac) 7.9 Permanent Pool Volume Provided (acre-ft) 5.7 Residence time Provided (days) 4 Water Quality Treatment Volume Calculations (TV) Water Quality Treatment Volume required (acre-ft) 20.1 Water Quality Treatment Volume provided (acre-ft) 0.8 Invert of Weir (ft-NGVD) 14.5 As can be seen from the table, the existing pond is estimated to achieve a 4-day residence time which is significantly less than the minimal desired residence time of 14 days required by the SJRWMD for wet detention systems. Wet detention basin efficiencies are based on a permanent pool storage volume that achieves average hydraulic residence time of at least 2 to 3 weeks. Under the SJRWMD requirements, this will be detention of the runoff from the first 1.0 to 2.5 inches of rainfall with a discharge of no more than one-half the treatment volume in the first 60 hours. As the pond was discharging during dry-weather conditions, CDM also assumed the control elevation was at or close to the assumed normal water level; therefore, a control elevation of 14.5 ft-NGVD was assigned for this purpose. Since this residence time is less than the optimal threshold of 14 to 21 days, the Walker equation was used to estimate the percent reduction in TP loads. The Walker equation is an empirical approach to nutrients removal in impoundments and takes into account the actual residence time of the pond. This approach is typically used when a proposed facility has a residence time of less than the optimum 14 to 21 day threshold. The Walker equations can be found in: "Empirical Methods for predicting Eutrophication in Impoundments", Chief of Engineers, U.S. Army Washington, Tech. Report E-81-5 Environ. Lab, Waterways Exp. Sta. Vicksburg, MS, 1985. Please note that this equation is used for off-line facilities. The Walker equation for TP removal is as follows: ~~ 50 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of tMnter Springs TMDL Master Plan 1+(1+4•K2•P •~,losl P = I 1J (Equation 5-1) 2•K2•T K2= 0.056•Qs'FoT QS +13.3 Where: (Equation 5-2) P; =Inflow total phosphorus (mg/m3) P =Total phosphorus released by the impoundment QS=Surface overflow rate (m/yr) F°t =Tributary ortho-P/Total P (unitless) T =Hydraulic residence time (years) K2 =Second order decay rate function (m3/mg-yr) The Walker Equation results in an estimated 4.2 percent reduction in TP by the existing pond under existing conditions fora 241 acre treatment area. Therefore the assigned 60 percent removal efficiency for TP for wet detention ponds that is used in the TMDL model seems to be an overestimate of existing load reduction in this particular case. Please note this calculation does not take into account the existing treatment provided by BMPs upstream of the pond within the same tributary area. This purpose of this exercise is to better gauge the existing treatment capacity of the pond based on existing conditions in order to compare it to estimated reductions as a result of the improvements. Incorporating the improvements to the pond previously described as well as taking into account the increased tributary area of 288 acres results in achieving a 14-day residence time (as shown in Table 8) .Therefore, the proposed pond would be able to achieve the anticipated treatment efficiency of 60 percent for TP removal. Table 8 City of Winter Springs TMDL Master Plan Highlands Subdivision Proposed Pond Residence Time Calculations Existing Tributary Area to Wet Detention Pond (acres) 288 Total % Impervious 25.8% Runoff Coefficient 0.38 Total Impervious Area (acres) 74.3 ~~ 51 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of lMnter Springs TMDL Master Plan Table 8 City of Winter Springs TMDL Master Plan Highlands Subdivision Proposed Pond Residence Time Calculations Pond Data Pond Side slope Ratio (Horizontal :Vertical - i.e. 4:1) 4 Bottom of Pond (ft-NGVD) 4.0 Top of Bank (ft-NGVD) 16.0 Pond area at Bottom (acres) 2.0 Pond area at NWL (acres) 3.2 Pond area at Weir (acres) 3.4 Pond area at Top of Bank (acres) 3.5 Permanent Pool Volume Calculations Calculation of Permanent Pool Volume required (acre-ft) 37.8 Normal Water Level (ft-NGVD) 14.0 Depth of Permanent Pool Volume (PPV, ft) 10.0 Average Area for PPV (Ac) 3.8 Permanent Pool Volume Provided (acre-ft) 26.0 Residence time Provided (days) 14 Water Quality Treatment Volume Calculations (TV) Water Quality Treatment Volume required (acre-ft) 24.0 Water Quality Treatment Volume provided (acre-ft) 5.0 Invert of Weir (ft-NGVD) 15.5 CDM used the existing gross load estimates calculated by FDEP using the TMDL pollutant loading model for the proposed tributary area previously shown in Figure 35. FDEP's load estimate for the proposed 288 acre tributary area as well as the anticipated load reductions are shown in Table 9. Table 9 City of Winter Springs TMDL Master Plan Highlands Subdivision Proposed Improvements TP Load Reduction Estimates FDEP Estimated TP Estimated TP Reduction Net TP Proposed TP Existing Reduction Improved due to Reduction Tributary Gross TP due to TP Proposed due to Area (ac) Load Removal Existing Removal Improvements proposed (Ibs) Efficiency Wet Pond Efficiency (Ibs) Improvements % Ibs % Ibs 288 115.7 4.2 4.9 60 69.4 64.5 ~~ 52 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of Winter Springs TMDL Master Plan 5.2 Gee Creek Subbasin 5.2.1 Buttonwood Avenue Stormwater Facility The North Orlando Terrace and North Orlando Second Addition subdivisions were identified as areas that do not have stormwater BMPs in place and runoff discharges directly into Gee Creek. A portion of this area is also served by reclaimed water. Approximately two feet of flooding at Moss Road near Dolphin Road was observed during Tropical Storm Fay. Based on this information, CDM developed a conceptual solution to address water quality as well as to reduce flooding in the area. A 7.3-acre parcel owned by the City is located on the west side of the subdivision near Buttonwood Avenue as shown in Figure 36. A stormwater detention area could be constructed on this parcel to provide treatment for approximately 77 acres of untreated residential area. This would also require some of the infrastructure to be modified in order to direct runoff to the pond as it currently flows directly to Gee Creek. A control structure would also be required to release overflow out of the pond. A schematic of the proposed improvement is shown in Figure 36. Additionally, for those areas of the subdivision not included in this tributary area (primarily the North Orlando Second Addition subdivision), it is recommended to retrofit the outfalls using aflow-through filtration system. These systems use replaceable cartridges containing several types of filter media to remove sediments, oil and grease, soluble metals, organic compounds, phosphorus and nitrogen. A typical sketch is provided in Attachment 1. Performance evaluation for the removal of TP has indicated that removal efficiencies can range from 53 to 78 percent. Accepted BMP efficiency values for the Lake Jesup BMAP provided by FDEP on July 22, 2008 did not include values for filter media. CDM consulted the International Stormwater BMP Database [1999-2008] prepared for agencies such as U.S. Environmental Protection Agency (USEPA), American Society of Civil Engineers (ASCE) and the Federal Highway Administration (FHWA). The median TP removal efficiency for media filters was 30 percent. The locations where flow-through filtration systems are proposed are also shown on Figure 36. For consistency with the Lake Jesup TMDL and the reasons cited above, treatment efficiency for TP of 60 and 30 percent for the proposed pond and flow-through filtration systems, respectively will be used in the pollutant load estimate portion of the TMDL Master Plan (Task 4 of the scope of services). Recommendations Based on this conceptual analysis, CDM recommends the following: ^ Construct a 4.1-acre pond on City-owned property on the west side of the North Orlando Terrace subdivision near Buttonwood Avenue; ^ Re-route existing drainage in the subdivision towards the proposed pond; ^ Provide control structure that directs pond overflow to the tributary north of Alderwood St.; and ^ Retrofit outfalls serving the North Orlando 2nd Addition with flow-through stormwater filtration. ~~ 53 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx d o m U7 y _ _ ~ N m ~ N W ~ ~ r C N G N a ` Q ~ o ~ 3 w U f a ~~ 2 o a c :~ c a a /~ W ~ L ~ calf d m ~ ~ ~ N N ~ 9 ~ W O f6 N 111 m ~ U7 N C .Q 4J t6 N r N N N N U ~ 3 0 L m ~ '(] ~ yr ~ § O 1 7 ~ Vi E N }a F Z~ . -__ %l J N o 0 o Q Q Q v pl a o ~ m =~ ~° `m ~' w m ~' ~ a m ~ ~ m ~ a Q r a ~ a a s a in ~ m U U o 0 0 ~ C7 Y ~ ~ b a r U ii in ~ a U ~° r 0.L i ~@ r_~ •; O 4 ~~~- ~ t 1 ~_ ~ p ~~~~,- y_. _._ i O 1 ~~ i q~~,~"~~~A t ~. ~F N~~~, ~ . 0 a v "wr d i+~ ~,~:~_~ .r.i•s t f. .•i fir. City of lMnter Springs TMDL Master Plan Estimated Load Reduction Using the SJRWMD criteria for wet detention, CDM performed calculations to estimate whether the proposed pond would achieve the desired residence time for water quality (and therefore quantity) treatment for the proposed tributary area of 77 acres. These calculations are provided in Table 10. Table 10 City of Winter Springs TMDL Master Plan Buttonwood Avenue Proposed Stormwater Facility Residence Time Calculations Existing Tributary Area to Wet Detention Pond (acres) 77 Total % Im ervious 23.9% Runoff Coefficient 0.37 Total Im envious Area acres 18.4 Pond Data Pond Sideslope Ratio (Horizontal :Vertical - i.e. 4:1) 4 Bottom of Pond (ft-NGVD) 42.0 To of Bank ft-NGVD 51.0 Pond area at Bottom acres 2.8 Pond area at NWL (acres) 3.6 Pond area at Weir acres 3.9 Pond area at To of Bank acres 4.1 Permanent Pool Volume Calculations Calculation of Permanent Pool Volume required (acre-ft) 9.7 Normal Water Level ft-NGVD 48.0 De th of Permanent Pool Volume PPV, ft 6.0 Average Area for PPV (Ac) 1.6 Permanent Pool Volume Provided (acre-ft) 19.4 Residence time Provided da s 42 Water Quality Treatment Volume Calculations (TV) Water Qualit Treatment Volume re uired acre-ft 6.4 Water Quality Treatment Volume provided (acre-ft) 6.6 Invert of Weir ft-NGVD 49.8 According to Table 10, the proposed pond would be able to provide the desired residence time to achieve the anticipated treatment efficiency. In the case of the TMDL pollutant loading model, a treatment efficiency of 60 percent has been assigned to wet detention ponds for TP removal. Therefore the net loading under proposed conditions can be calculated using the following equation: ~~ 55 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of lMnter Springs TMDL Master Plan Net Loadingpro =Net LoadingeXst (1-BMP removal efficiency) (Equation 5-3) FDEP provided existing load estimates using the TMDL pollutant loading model for the proposed tributary area previously shown in Figure 36. Using FDEP's load estimate for the proposed tributary area shown in Table 11, the proposed net loading is: Net Loadingpro = (11.421bs/yr) (1- 0.6) = 4.61bs/ yr For the proposed filtration devices, CDM used the median TP removal efficiency of 30 percent for media filters previously cited from the International stormwater BMP Database [1999-2008] to calculate the proposed net loading: Net Loadingpro = (10.221bs/yr) (1- 0.3) = 7.21bs/ yr Table 11 City of Winter Springs TMDL Master Plan Buttonwood Avenue Proposed Improvements TP Load Reduction Estimates Proposed FDEP TP Proposed Net Estimated Tributary Area FDEP Gross Reduction due FDEP Net TP TP Loading TP Load (ac) Load (Ibs) to Existing Load (Ibs) (Ibs/yr) Reduction BMPs (Ibs) (Ibs/yr) 77 (pond) 14.2 2.8 11.4 4.6 6.8 49(filtration) 10.2 0.40 9.8 7.2 2.6 5.2.2 Hacienda Village Hacienda Village is a mobile home residential area situated on the north and south banks of Gee Creek. This area currently does not have any stormwater BMPs and runoff discharges directly into Gee Creek. As significant flooding occurred here during Tropical Storm Fay, the City has expressed interest in planning a project that provides both water quality and flood control benefits. Due to the lack of available open space on the property itself, the only viable area appears to be a long stretch of open space along the north bank of the creek. Based on review of the National Wetlands Inventory (NWI), no wetlands have been identified along this stretch of bank. It maybe possible to construct a 1.6-acre linear detention pond along this stretch of bank and redirect the stormwater outfalls from the mobile home park to the pond. However, environmental due diligence should be performed to verify that there are indeed no riparian wetlands where the pond is proposed. Public involvement is also recommended during the planning and design phases of such a project as the proposed pond is in close proximity to several nearby residents. During extreme events such as Tropical Storm Fay, the pond would most likely not reduce stages in Gee Creek itself as a portion of the mobile home park is located within the creek's natural floodplain. However, it would provide some water quality benefits in terms of reducing pollutant loads as well as some additional storage that may alleviate flood stages for some of the less severe storm events. This pond could ~~ 56 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of tMnter Springs TMDL Master Plan also act as an off-line facility to treat discharge from Gee Creek during low flow conditions. It is recommended to retrofit the remaining existing stormwater outfalls on the north and south side of Gee Creek with flow-through filtration systems, as shown in Figure 37. Performance evaluation for the removal of TP has indicated that removal efficiencies can range from 53 to 78 percent. Accepted BMP efficiency values for the Lake Jesup BMAP provided by FDEP on July 22, 2008 did not include values for filter media. CDM consulted the International stormwater BMP Database [1999-2008] prepared for agencies such as USEPA, ASCE and FHWA. The median TP removal efficiency for media filters was 30 percent. Therefore, CDM will use a removal efficiency of 30 percent as a conservative estimate. Recommendations Based on this conceptual analysis, CDM recommends the following: Determine the feasibility of constructing a 1.6-acre linear detention pond along the north banks of Gee Creek to address such challenges as elevation limitations and permitting constraints (i.e., wetlands); ^ If the project is determined to be feasible, provide opportunities for public involvement throughout the planning and design stages; and ^ Retrofit outfalls on north and south banks of Gee Creek with flow-through stormwater filtration. Estimated Load Reduction Using the SJRWMD criteria for wet detention, CDM performed calculations to estimate whether the proposed pond would achieve the desired residence time for water quality (and therefore quantity) treatment for the proposed tributary area of 52 acres. These calculations are provided in Table 12. Table 12 City of Winter Springs TMDL Master Plan Hacienda Village Proposed Wet Detention Pond Residence Time Calculations Existin Tributar Area to Wet Detention Pond acres 52 Total % Impervious 12.9% Runoff Coefficient 0.29 Total Impervious Area (acres) 6.7 Pond Data Pond Sideslo e Ratio Horizontal :Vertical - i.e. 4:1 4 Bottom of Pond ft-NGVD 23.0 To of Bank ft-NGVD 33.0 Pond area at Bottom (acres) 0.8 ~~ 57 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of lMnter Springs TMDL Master Plan Table 12 City of Winter Springs TMDL Master Plan Hacienda Village Proposed Wet Detention Pond Residence Time Calculations Pond area at NWL acres 1.2 Pond area at Weir acres 1.6 Pond area at Top of Bank (acres) 1.6 Permanent Pool Volume Calculations Calculation of Permanent Pool Volume re uired acre-ft 5.2 Normal Water Level ft-NGVD 29.0 Depth of Permanent Pool Volume (PPV, ft) 6.0 Avera e Area for PPV Ac 0.9 Permanent Pool Volume Provided (acre-ft) 6.0 Residence time Provided da s 24 Water Quality Treatment Volume Calculations (TV) Water Quality Treatment Volume required (acre-ft) 4.3 Water Qualit Treatment Volume rovided acre-ft 4.9 Invert of Weir (ft-NGVD) 32.5 According to Table 12, the proposed pond would be able to provide the desired residence time to achieve the anticipated treatment efficiency. In the case of the TMDL pollutant loading model, a treatment efficiency of 60 percent has been assigned to wet detention ponds for TP removal. FDEP provided existing load estimates using the TMDL pollutant loading model for the proposed tributary area previously shown in Figure 37. Using FDEP's load estimate for the proposed tributary area shown in Table 13 and Equation 5-3, the proposed net loading is: Net Loadingpro = (5.51bs/yr) (1- 0.6) = 2.21bs/ yr For the proposed filtration devices, CDM used the median TP removal efficiency of 30 percent for media filters previously cited from the International Stormwater BMP Database [1999-2008] to calculate the proposed net loading: Net Loadingpro = (0.621bs/yr) (1 - 0.3) = 0.431bs/ yr Table 13 City of Winter Springs TMDL Master Plan Hacienda Village Proposed Improvements TP Load Reduction Estimates Proposed FDEP TP Proposed Net Estimated Tributary Area FDEP Gross Reduction due FDEP Net TP TP Loading TP Load (ac) TP Load (Ibs) to Existing Load (Ibs) (Ibs/yr) Reduction BMPs Ibs Ibs/ r 52 (pond) 5.5 0.00 5.5 2.2 3.3 6.4(filtration) 0.62 0.01 0.61 0.43 0.18 ~~ 58 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx m N U 0 ~ ~ ~ E - m m ~ ii7 0 ~ m ~ E m ~_ ~ C li ~ N ~ r ~] a C ~ C m ~ 4 ~ 'o a v n v v m of U i in ~ ~ 3 ~ °- ~ m a n c ~ N N N N N N ~ ~ ~ ~ L ~ m a ~ H ~ Q ~ O C ~ ~ y ~ c°i °a. a a afi a ~~ v ~ U e " ~ cri 3 ~ v m ~ m '° m ~ v °° a„+ ~ ~ a ° ° Q Q ° ° m ~ ~ a a ~ m -- ~° m ~° m m ~-' r a~ a o ~' ~' m ii ti a a a I~ a x 7i ~ m c~ v ^ o ^ ii [~ _ ~ ~ D a ~ c~ a in ~ i1 a 4 wbri V~• Ea D D• P D• D 6••• I - u i_. ~ J ~~ ~d m a~ e m ~~ O J 7.~ .~ ~ ~ d O ~- ~1 ~, _ ~--.1 a n vs cri a~ ay ~} Q a~ V! L7 g 0 a a~ } c .~ City of Winter Springs TMDL Master Plan 5.2.3 N. Orlando Ranches Sections 2A, 9 & 10 & Winding Hollow Subdivision The North Orlando Ranches subdivision was identified as an area with limited stormwater treatment (i.e., swales) and is served by underdrains that discharge directly to a waterway, Gee Creek in this case. Just to the east, the Winding Hollow Subdivision, although equipped with stormwater BMPs, has underdrains that discharge directly to one of Gee Creek's main tributaries. Both the North Orlando Ranches and Winding Hollow subdivisions experienced significant roadway flooding during Tropical Storm Fay. Winding Hollow was constructed in a historical wetland and its stormwater ponds discharge to where Gee Creek, No Name Creek and the overflow from the Little Lake Howell subbasin all converge. There are two large City-owned parcels which comprise 31 acres, located between the two subdivisions as shown on Figure 38. Wetlands occupy both of these parcels based on the NWI. These wetlands appear to have once been part of the larger historical wetland system to the east where Little Lake Howell overflows. However; due to development of the Winding Hollow subdivision and the power easement, these two wetland areas have been isolated over time. The City may want to consider enhancing surface water flows to the wetland area within these two parcels which will provide additional attenuation, water quality treatment and wetland re-hydration. 62-25.042, F.A.C sets forth the permit requirements for wetland stormwater discharge facilities. The underdrains from Winding Hollow that currently discharge directly into No Name Creek could be piped so that they discharge into the wetland area. As the North Orlando Ranches Subdivision is located on the west side of No Name Creek, it would not be possible to route stormwater runoff across the creek into the wetland area. Therefore, it is recommended to install a low flow weir that will divert flow from No Name Creek into the wetland area. Off-line baffle boxes should also be installed to provide pre-treatment for the wetland. A control structure would allow for rehydration of the wetland treatment system and would also allow water to discharge during times of high flow. Recommendations Based on this conceptual analysis, CDM recommends the following: ^ Rehydrate the 31-acre wetland on City-owned property to the north of the Winding Hollow subdivision; ^ Re-route the underdrain discharge on the west side of the subdivision to the north into the wetland area; ^ Install an overflow weir to divert flow from No Name Creek into the wetland treatment system; and ^ Install baffle boxes for pre-treatment and a control structure to re-hydrate and regulate discharge from the wetland system. ~~ 60 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx c m ~ ~ E ~ 3 3 ~ C L ~' d7 v H N O +n cy ~ n~n a w U} ~ C t O LL D a ~ C f6 ~ ~ C C ~ y to C ~ ~ R 0 C D ~ 61] pT ~ ~„~ U v ~ ~ O1 JJ ~ ~ O W t3 } ~ C (Y ~ ~ 4 a ~ ~ .u C e`o N ~ C Q - ~ ~ N C1 .I- L7 n, m aai ~ s°u cai ~j ~ v~ a 2 0 ~ W o ~ a ~ a'r a Y m ~ ~ ~ = C = ~ ~ a a i~ a ~ in e m° v r~ n cs a ~ ~ x ~ ~ a d ~ ~ ~ ~ in a ~ ~, a ~ .~ - ~ o ~ ~ ~ '~ • o ~ • o e • o ^ o • • ~~ _~ ~ ©~o ~ ~c~+o 0 C ~ '~J - - - __~`' Y _-_-_ -. ~.---- O O J O G p ,~G~ ~~ ~ Q a ~r„ , `~ Q n v o o ~ -~_--, -`o ~ u v ~ rs o ;?7 a ~ ° o a ° ° ~~ o ~'~~ ~ h k ¢ o ~' ,i a cP ~ ~a 1~-~ 1J i} OO O D Ca O O t7 v S ~' fJ ^ ~ O f ~ . O (? p d 79 O ~..' 00 D '~ ^ rnU O O i ' r~ U k y d Cy q~ ~p ~ t D Q ~n n ~. _ ® a+ [l ~~7 [s ii ~ . `~rwl ~~ ~~ tt ~- ,~! O ~~r~`- g ~' y, ~._~. ~~ ~. ~,~•F' ~~;; ,, ;.~ ~_\ , , ~a u, ~~ ~,~ [~ d yy ~~ ~1L - - c ~ Q J a r_ ~~ ~~ gay City of lMnter Springs TMDL Master Plan Estimated Load Reduction Stormwater wetland systems use natural and constructed wetlands to treat stormwater. These systems often have open water or pond components for attenuation and pre-treatment. Specific types of stormwater wetland systems include natural marshes and swamps, constructed marshes, pond/wetland systems, and extended detention wetlands. The frequency and duration of storm events and the time between storm events affect the efficiency of these systems (Wong et al. 1992). Because the actual flow rates vary, the detention time and hydraulic loading are variable, and sizing criteria have been developed in terms of this variability. One approach for sizing these systems is to provide a runoff treatment volume that captures 90 percent of the annual runoff volume in the region (Schueler 1992). Another approach to sizing is for the wetland to watershed area ratio (WWAR) to be 2 percent for shallow marshes and 1 percent for pond/wetland and extended detention wetlands (Schueler 1992 and Strecker et a1.1992). In terms of treatment performance Schueler (1992) indicates that the pollutant removal rates for stormwater wetlands are similar to conventional pond systems, such as dry extended detention and wet ponds. In many cases, suspended solids removal rates were higher than conventional ponds and phosphorus removal rates were more variable and in some cases slightly lower than in wet ponds. The most reliable overall performance was achieved by pond/wetland systems. Hunt and Doll (2000) indicate that compared with ponds, sand filters, bio-retention area, and other practices, stormwater wetlands have the best median removal rate for total suspended solids, nitrate-nitrogen, ammonia-nitrogen, total phosphorus, phosphate-phosphorus, and some metals. These authors present average pollutant removal percentages for selected constituents as presented in Table 14 (adapted from Brown and Schueler 199'x. Table 14 City of Winter Springs TMDL Master Plan Pollutant Removal Effectiveness for Stormwater Wetlands Pollutant Number of Samples Median Pollutant Removal Percenta a Range for Projects Investi ated Total suspended sediment 35 78% -29% to 99.5% Soluble phosphorus 15 40% -34.5% to 75% Total phosphorus 35 51 % -9% to 99.5% Ammonia (as NHq) 19 43% -55.5% to 72% Nitrate-nitrogen 30 67% -100%to 90% Organic nitrogen 12 1 % -31 % to 43% Total Kjeldahl nitrogen (TKN) 10 14.5% -10.3%to 81% Total nitrogen 22 21% -25%to 83% Copper 10 39.5% 2% to 84% Lead 17 63% 23% to 94% Zinc 16 53.5% -73.5% to 90% ~~ 62 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of Winter Springs TMDL Master Plan For the purposes of estimating the TP load reduction for the proposed improvement utilizing the existing wetland within the Winding Hollow Subdivision, CDM applied design methodologies developed by Kadlec et. al. (2009) for stormwater wetlands. As the recommended project is conceptual in nature and existing data are limited, CDM used the wetland-to-watershed area ratio (WWAR) method for sizing the wetland based on the estimated tributary area: Watershed Area = 2,787 ac Available Wetland Area = 31 ac Annual rainfall = 51 in/yr Average Annual Rainfall Rate = (51in/yr)(yr/365days) = 0.14 in/day Watershed Runoff Coefficient = 0.4 Runoff = (0.14 in/day)(0.4) = 0.56 in/day 0.56 in/day = 0.14 cm/day WWAR = 100 (31 ac/2787 ac) = 0.96% Watershed/Wetland Area Ratio = 1/0.011 = 90.9 Average Annual Wetland Hydraluic Loading Rate from the Watershed = (90.9)(0.14cm/day) = 12.7 cm/day = 46.5 m/yr Since the WWAR is on the low end of the optimal range of 1 to 5 percent specified by Kadlec et. al (2009) for sizing, it is presumed that the natural wetland treatment system for Winding Hollow would achieve a TP removal of something less than the median value of 51 percent specified in Table 14 for stormwater wetlands. Regression equations for the purpose of sizing can be used to calculate the TP remaining based on hydraulic loading rate: TP (% remaining) = 12g0~44 RZ = 0.71 Where: q =hydraulic loading rate (m/yr) Applying the equation results in: TP (% remaining) = 12(46.5)044 = 65% Therefore, based on the equations previously presented, one could expect an approximate removal rate of 35 percent for the system in question. ~~ 63 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of lMnter Springs TMDL Master Plan FDEP provided existing load estimates using the TMDL pollutant loading model for the proposed tributary area. For the wetland system, CDM applied the TP removal efficiency of 35 percent to calculate the proposed net loading from the Winter Springs tributary area (1,959 acres). Using FDEP's load estimate for the proposed tributary area provided in Table 15 and Equation 5-3, CDM calculated the proposed net loading: Net Loadingpro = (576.71bs/yr) (1- 0.35) = 3751bs/ yr Table 15 City of Winter Springs TMDL Master Plan N. Orlando Ranches/Winding Hollow Proposed Improvements TP Load Reduction Estimates Proposed FDEP Gross FDEP TP FDEP Net TP Proposed Net Estimated Tributary Area TP Load (Ibs) Reduction due Load (Ibs) TP Loading TP Load (ac) to Existing (Ibs/yr) Reduction BMPs (Ibs) (Ibs/yr) 1,959 (wetland) 748.7 164.9 576.7 375 201.7 5.2.4 North Orlando Townsite Subdivision The North Orlando Townsite subdivision is located just south of SR419 within the Gee Creek subbasin. With the exception of underdrains, the subdivision does not have stormwater treatment in place. The eastern portion of the subdivision discharges directly into a tributary of Gee Creek, while the western portion discharges through a series of stormwater pipes that ultimately outfall to the large wetland system that is contiguous with Soldiers Creek. There are no City-owned parcels within close vicinity to the subdivision. Due to site constraints, it is recommended to retrofit the stormwater outfalls with flow-through filtration systems as shown on Figure 39. As several other stormwater management systems discharge to the western outfall, some benefit in pollutant load reduction would also be realized. ~~ 64 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx v e ~ v = O LL d N u c ~ c m w m r z ~ 9G ~ Y ~ ~ V ~ C ~ 0 C ~ ~ ! ~ ~ ~ ~ ~ U7 _N ~ O ~ ~ p @ N LLl v V ~~ ~ B CC3 ~ ~_ __ :/' ~ ~ ~_ ~ ~ a ~ m v° a ~ ~ a m D W ~~ N E e D J ui o ~ ~ a o ~ m ~° m ~° m m S si ~ ~. c o 6 h LL vr, ~ m t~ c} ^ ® ^ ~ c3 ~ ~ ~ C]a' ~ cs ~ a cn ~ z v i C_? Q P i p p i D D i i i I~ ~~ ~d m a~ e m ~~ O J 7.~ ~ ~ a~ a~ ~ ~ _~ Q 4) V! g 0 a Q .~ .~ a s3 s~ ;~ 0 v -c3 Q a City of lMnter Springs TMDL Master Plan Recommendations Based on this conceptual analysis, CDM recommends to retrofit the eastern and western outfalls with flow-through off-line stormwater filtration devices. Estimated Load Reduction FDEP provided existing load estimates using the TMDL pollutant loading model for the proposed tributary area. For the proposed filtration devices, CDM used the median TP removal efficiency of 30 percent for media filters previously cited from the International stormwater BMP Database [1999-2008] to calculate the proposed net loading. Using FDEP's load estimate for the proposed tributary area provided in Table 16 and Equation 5-3, CDM calculated the proposed net loading: Net Loadingpro = (17.41bs/yr) (1 - 0.3) = 12.21bs/ yr Table 16 City of Winter Springs TMDL Master Plan North Orlando Townsite Proposed Improvements TP Load Reduction Estimates Proposed FDEP Gross FDEP TP FDEP Net TP Proposed Net Estimated Tributary Area TP Load (Ibs) Reduction due Load (Ibs) TP Loading TP Load (ac) to Existing (Ibs/yr) Reduction BMPs (Ibs) (Ibs/yr) 75 filtration 18.8 1.4 17.4 12.2 5.2 5.3 Howell Creek Subbasin 5.3.1 Tuscawilla Country Club The Tuscawilla Country Club was identified as a potential stormwater retrofit site as it currently does not have stormwater BMPs in place and irrigates with reclaimed water. Howell Creek runs through the middle of the golf course and receives untreated runoff from the various greens and fairways adjacent to the creek. There are a number of wet detention ponds located on the southeast side of Howell Creek throughout the golf course that currently serve adjacent residential developments (Figure 40). To reduce the nutrient loading associated with reclaimed water, it is recommended to replace reclaimed water as the primary source of irrigation with stormwater reuse, using the various wet detention ponds as the irrigation source. Reclaimed water may be used as a backup source when the detention ponds cannot meet irrigation demand. This would not only reduce the nutrient loading associated with reclaimed water, but would also increase the treatment efficiency for those surrounding subdivisions as discharge from these ponds would either be eliminated altogether or drastically reduced. A modification of the existing environmental resource permits (ERPs) for these stormwater management systems would be required in order to convert the existing ponds to stormwater reuse ponds. There are approximately 185 acres of residential development currently served by wet ponds adjacent to the golf course. Several of these ponds are also maintained by the City. ~~ 66 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx m y N a v C ~ p ~ 6 LL. a¢ ~ ~ o ~ U) N aY 3 ' N j ~ G E N c w ~ ' , a 9Y ~ v ~ ~ m w p ~, - ~i 9C U y ~ m CL W W Il ~ LL ~ C ~ ~ 4i CI] C.7 ~ p in N ~ ~ ~ m ~ E ~ O ~ p ~ 1 N i3 '~ a ~ L ~ . - v O ~ = ~ iR ~ N R ~ G ~ ~ N LL Ln C Z _ '.F F ~;J N b y ~ J ^. N o F 4L ~ aa rj} ~ m ,C] o ~~ = U V L] O ` m m m ~ C5 IJa C7 Z ~ W ~ ~ ~ Q a. a~ ~ a p. r1 H U SL U7 , „ m [i7 VJ ~ ~ C3 W s '' O D i® O! 0 0 0 i i I' _ L_ O Crs .Q ~ CJ} iL L L p J ~~ ±'' ~ ~~ o ~ r3) cll ~ ~ ~_ LL p rQ. C Vi !7 Q O S~ 3 U a U ~s .~ c~ a City of Winter Springs TMDL Master Plan The SJRWMD requires that a portion of the runoff from the site must be stored in the pond and subsequently withdrawn through the reuse system. For systems which discharge to Class III receiving water bodies, the rule specifies that the system reuse at least 50 percent of the average annual runoff discharging to the reuse pond. Based on FDEP's TMDL Pollutant Load Model, these areas generate 64.9 ac-ft of runoff volume per year. Based on the SJRWMD's rule, the reuse systems would require at least 32.5 ac-ft of volume in order to be permittable. This would be volume in addition to what is already within the permanent pool of each pond. In FDEP's "Guidance for Entities Estimating Urban Nonpoint Source Load Reductions" prepared for the Lake Jesup BMAP Technical Working Group, FDEP identifies stormwater reuse as an accepted practice and that it "...may be eligible for up to 100% TP load reduction credit, depending on the design of the project." The treatment efficiency assigned to wet detention ponds in the Lake Jesup TMDL is 60 percent for TP. By implementing a stormwater reuse system, the treatment efficiency of these ponds could be increased while nutrient loads to Howell Creek from reclaimed water may be reduced. In addition to the stormwater reuse system, it is recommended to construct several small detention areas adjacent to where the golf course crosses Howell Creek. Currently, there are no measures in place to prevent runoff directly into the Creek. These could be incorporated into the fairways such that they act as water hazards while capturing the first flush of stormwater runoff from the golf course. There are four creek crossings and it is recommended to place a water feature on both sides of the creek as shown in Figure 40. Recommendations Based on this conceptual analysis, CDM recommends the following: ^ Convert existing subdivision wet detention ponds to stormwater reuse ponds that will be used to irrigate the golf course; ^ Incorporate water features adjacent to Howell Creek that will capture runoff from the golf course; and ^ Consider management activities to help reduce nonpoint source runoff to Howell Creek. Estimated Load Reduction As mentioned previously, in FDEP's "Guidance for Entities Estimating Urban Nonpoint Source Load Reductions" prepared for the Lake Jesup BMAP Technical Working Group, FDEP identifies stormwater reuse as an accepted practice and that it "...may be eligible for up to 100% TP load reduction credit, depending on the design of the project..." and projects will need to be evaluated on a case-by-case basis. To be somewhat conservative, CDM estimated the removal efficiency at less than 100 percent for the stormwater reuse retrofit project. Therefore a removal efficiency of 90 percent was used for the purpose of calculating the proposed net loading: ~~ 68 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of lMnter Springs TMDL Master Plan Net Loadingpr° _ (33.1 lbs/yr) (1 - 0.9) = 3.31bs/ yr. CDM estimated that each water feature would be approximately 0.1 ac and a total of six (6) would be required to capture runoff into the creek. As the land use type is consistent for the individual proposed tributary areas, CDM estimates a 0.6 ac pond would treat the combined proposed tributary area of 6.4 acres. For the purposes of evaluating the SJRWMD criteria for wet detention, CDM performed calculations to estimate whether the proposed pond would achieve the desired residence time for water quality (and therefore quantity) treatment for the proposed tributary area. These calculations are provided in Table 17. Table 17 City of Winter Springs TMDL Master Plan Tuscawilla Country Club Proposed Water Features Residence Time Calculations Existing Tributary Area to Wet Detention Pond (acres) 6 Total % Impervious 4.10% Runoff Coefficient 0.23 Total Impervious Area (acres) 0.3 Pond Data Pond Sideslope Ratio (Horizontal :Vertical - i.e. 4:1) 4 Bottom of Pond (ft-NGVD) 33.0 Top of Bank (ft-NGVD) 39.0 Pond area at Bottom (acres) 0.3 Pond area at NWL (acres) 0.4 Pond area at Weir (acres) 0.5 Pond area at Top of Bank (acres) 0.6 Permanent Pool Volume Calculations Calculation of Permanent Pool Volume required (acre-ft) 0.5 Normal Water Level (ft-NGVD) 36.0 Depth of Permanent Pool Volume (PPV, ft) 3.0 Average Area for PPV (Ac) 0.2 Permanent Pool Volume Provided (acre-ft) 1.1 Residence time Provided (days) 46 Water Quality Treatment Volume Calculations (TV) Water Quality Treatment Volume required (acre-ft) 0.5 Water Quality Treatment Volume provided (acre-ft) 1.0 Invert of Weir (ft-NGVD) 38.0 ~~ 69 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of lMnter Springs TMDL Master Plan According to Table 17, the proposed water features would provide the desired residence time to achieve the anticipated treatment efficiency. In the case of the TMDL pollutant loading model, a treatment efficiency of 60 percent has been assigned to wet detention ponds for TP removal. FDEP provided existing load estimates using the TMDL pollutant loading model for the proposed tributary area previously shown in Figure 40. Using FDEP's load estimate for the proposed tributary area shown in Table 18 and Equation 5-3, the proposed net loading is: Net Loadingpro = (6.21bs/yr) (1- 0.6) = 2.51bs/ yr Table 18 City of Winter Springs TMDL Master Plan Tuscawilla Country Club Proposed Improvements TP Load Reduction Estimates Proposed FDEP Gross FDEP TP Net TP Load Proposed Net Estimated Tributary Area TP Load (Ibs) Reduction due (Ibs) TP Loading TP Load (ac) to Existing (Ibs/yr) Reduction BMPs (Ibs) (Ibs/yr) 185 (stormwater 75.8 42.8 33.1 3.3 29.8 reuse 21.8 wet onds 6.4 0.2 6.2 2.5 3.7 5.3.2 Winter Springs Boulevard Pond at Bear Creek The existing stormwater pond located on the north side of Winter Springs Boulevard adjacent to Bear Creek and serves a portion of the surrounding roadway. The pond was inspected during CDM's field reconnaissance in March 2008 and was observed to contain dense vegetation floating on the surface and continuous discharge from the control structure to Bear Creek. The presence of dense floating vegetation indicates a euthrophic system (i.e., high levels of nutrients); however, the source of nutrients was not entirely evident. There is a large network of underdrains associated with this system as shown in Figure 41. It may be beneficial to obtain water quality samples from the pond as well as the underdrains to determine the concentration and types of nutrients (i.e., nitrogen and phosphorus) present. Multiple grab samples based on storm events are recommended as they may be more indicative of non-baseflow conditions, although baseflow grab samples may help determine baseflow loads. Additionally, a sediment sample from the pond may indicate if there are legacy sediments present and if these are contributing to the nutrient load in the pond. The surrounding subdivisions also irrigate with reclaimed water which may be causing additional nutrient input into the system. Harper et. al. (1999) calculated removal efficiencies for changes in water quality concentration during migration through an underdrain outflow system. The research found that migration through the underdrain system appeared to reduce measured concentrations of dissolved organic nitrogen and particulate nitrogen, while increasing measured concentrations of ammonia and nitrate. On an overall basis, total nitrogen concentrations were reduced by approximately 37% within the filter underdrain system. Although the filter system appeared capable of removing total ~~ 70 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of Winter Springs TMDL Master Plan nitrogen, the long-term fate of these pollutants in the filter system was uncertain. Measured concentrations of orthophosphorus, particulate phosphorus, and total phosphorus were found to increase in concentration during migration through the underdrain filter system. Conversion of trapped particulate matter in the filter media into dissolved forms was observed for several parameters, such as ammonia, nitrate, and orthophosphorus. Based on observations and discussion with the City, it is recommended to increase the size of the existing pond from 0.17 acres to 0.8 acres. A wet pond is located directly to the north of the Winter Springs Boulevard pond and is separated by a berm. It is recommended to remove the berm and join these two ponds in order to increase the pond footprint. The existing control structure should also be relocated to the northwest corner of the new pond footprint and modified as dry-weather flow from the pond was observed during the field visit. Relocating the control structure will avoid "short-circuiting" and increase detention times in the pond. If it is determined that the underdrains (and weir elevation) are the source of excess nutrients, the City may want to consider replacing these with pipes as the increased pond size may accommodate the additional flow. If results from the sediment sample indicate sediments are a potential source, excavation of the pond and removal of other algal or accumulated vegetation is also recommended. A detailed hydrologic and hydraulic analysis should be performed to determine this. Overall, the recommended activities will increase the treatment efficiency of the pond. Recommendations Based on this conceptual analysis, CDM recommends the following: ^ Obtain a water quality samples (multiple grab samples) of the pond influent and effluent to characterize groundwater baseflow and determine actual efficiency; ^ Obtain a sediment sample from the pond to determine if legacy sediments are contributing to high nutrient concentrations; ^ Excavate existing pond area as necessary while removing accumulated algal growth and vegetation; ^ Increase the size of the existing 0.17-acre pond to 0.8 acres using the pond to the north; ^ Relocate and modify the control structure of the pond to improve its performance; and ^ Obtain a water quality sample in the underdrain system to determine the source of excess nutrients. ~~ 72 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of lMnter Springs TMDL Master Plan Estimated Load Reduction As mentioned previously, CDM observed that the existing wet pond was continuously discharging during dry-weather which indicated that the pond may not be achieving its design treatment efficiency. FDEP's TMDL pollutant loading model assumes that existing BMPs are providing the assigned treatment efficiency (i.e., 60 percent TP removal for wet detention). Based on this assumption and field conditions, CDM felt that the existing pond is achieving a treatment efficiency that is something less than the 60 percent assigned by the model. Using existing information as well as some assumptions, CDM performed calculations, provided in Table 19, to estimate whether the pond is achieving the desired residence time for water quality (and therefore quantity) treatment for the existing tributary area of 8.6 acres. Table 19 City of Winter Springs TMDL Master Plan Winter Springs Boulevard Existing Pond Residence Time Calculations Existing Tributary Area to Wet Detention Pond (acres) 9 Total % Impervious 31.2% Runoff Coefficient 0.42 Total Impervious Area (acres) 2.7 Pond Data Pond Sideslope Ratio (Horizontal :Vertical - i.e. 4:1) 4 Bottom of Pond (ft-NGVD) 20.0 Top of Bank (ft-NGVD) 26.0 Pond area at Bottom (acres) 0.0 Pond area at NWL (acres) 0.1 Pond area at Weir (acres) 0.1 Pond area at Top of Bank (acres) 0.2 Permanent Pool Volume Calculations Calculation of Permanent Pool Volume required (acre-ft) 1.2 Normal Water Level (ft-NGVD) 23.0 Depth of Permanent Pool Volume (PPV, ft) 3.0 Average Area for PPV (Ac) 0.4 Permanent Pool Volume Provided (acre-ft) 0.2 Residence time Provided (days) 3 Water Quality Treatment Volume Calculations (TV) Water Quality Treatment Volume required (acre-ft) 0.7 Water Quality Treatment Volume provided (acre-ft) 0.05 Invert of Weir (ft-NGVD) 23.5 ~~ 73 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of lMnter Springs TMDL Master Plan As can be seen from the table, the existing pond under is estimated to achieve a 3-day residence time which is significantly less than the minimal desired residence time of 14 days required by the SJRWMD for wet detention systems. Wet detention basin efficiencies are based on a permanent pool storage volume that achieves average hydraulic residence time of at least 2 to 3 weeks. Under the SJRWMD requirements, this will be detention of the runoff from the first 1.0 to 2.5 inches of rainfall with a discharge of no more than one-half the treatment volume in the first 60 hours. As the pond was discharging during dry-weather conditions, CDM also assumed the control elevation was at or close to the assumed normal water level, therefore a control elevation of 23.5 ft-NGVD was assigned for this purpose. Since this residence time is less than the optimal threshold of 14 to 21 days, the assigned 60 percent removal efficiency for TP for wet detention ponds that is used in the TMDL model seems to be an overestimate of existing treatment efficiency in this case. Since the Walker Equation cannot be applied in this instance as this is not an off- line facility, CDM estimated the current treatment efficiency based on the water quality treatment provided compared to the water quality treatment required as shown above in Table 19. Using this ratio, CDM estimated the current treatment efficiency for TP removal is 7.1 percent. Incorporating the improvements to the pond previously described results in achieving a 28-day residence time (as shown in Table 20). Table 20 City of Winter Springs TMDL Master Plan Winter Springs Boulevard Proposed Pond Residence Time Calculations Existing Tributary Area to Wet Detention Pond (acres) 9 Total % Impervious 31.2% Runoff Coefficient 0.42 Total Impervious Area (acres) 2.7 Pond Data Pond Sideslope Ratio (Horizontal :Vertical - i.e. 4:1) 4 Bottom of Pond (ft-NGVD) 20.0 Top of Bank (ft-NGVD) 26.0 Pond area at Bottom (acres) 0.5 Pond area at NWL (acres) 0.6 Pond area at Weir (acres) 0.7 Pond area at Top of Bank (acres) 0.8 Permanent Pool Volume Calculations Calculation of Permanent Pool Volume required (acre-ft) 1.2 Normal Water Level (ft-NGVD) 23.0 Depth of Permanent Pool Volume (PPV, ft) 3.0 Average Area for PPV (Ac) 0.4 ~~ 74 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of lMnter Springs TMDL Master Plan Table 20 City of Winter Springs TMDL Master Plan Winter Springs Boulevard Proposed Pond Residence Time Calculations Permanent Pool Volume Provided (acre-ft) 1.6 Residence time Provided (days) 28 Water Quality Treatment Volume Calculations (TV) Water Quality Treatment Volume required (acre-ft) 0.7 Water Quality Treatment Volume provided (acre-ft) 1.0 Invert of Weir (ft-NGVD) 24.5 According to Table 20, the proposed improvements would provide the desired residence time to achieve the anticipated treatment efficiency. In the case of the TMDL pollutant loading model, a treatment efficiency of 60 percent has been assigned to wet detention ponds for TP removal. FDEP provided existing gross load estimates using the TMDL pollutant loading model for the tributary area of 8.6 acres. Table 21 shows the estimated existing reduction by the pond using a treatment efficiency of 7 percent versus the pond with the improved treatment efficiency of 60 percent. Table 21 City of Winter Springs TMDL Master Plan Winter Springs Boulevard Proposed Pond Improvements TP Load Reduction Estimates Proposed FDEP Estimated TP Reduction Estimated TP Reduction due Tributary Area Gross TP Existing TP due to Existing Improved TP to Proposed (ac) Load (Ibs) Treatment Wet Pond (Ibs) Treatment Improvements Efficienc Efficienc Ibs 8.6 (wet pond) 2.5 7.1 0.18 60.0 1.5 5.3.3 Winter Springs and Wedgewood Subdivisions The Winter Springs Subdivision is located at the most upstream point of the Howell Creek subbasin within the City limits. Currently Winter Springs Units 2 and 3 and Wedgewood subdivisions have limited stormwater treatment in the form of swales while portions of Unit 4 are treated with wet detention. As this area is built out and there is no City-owned land or open available space in close proximity, it is recommended to retrofit the stormwater outfalls to the creek with flow-through off-line filtration devices. The filtration devices will provide some treatment for Units 2 and 3 (278 acres) and will increase the efficiency of treatment for Unit 4 (190 acres) (i.e., treatment train). There is some additional area to the east of these subdivisions as well as a small portion of the golf course that would also benefit. There are six (6) outfalls along the creek, as shown in Figure 42, that were identified as candidates for retrofit. Recommendations Based on this conceptual analysis, CDM recommends to retrofit the six (6) existing stormwater outfalls to Howell Creek with flow-through off-line filtration devices. ~~ 75 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx c _ a '~ ~ LL d ~ ~ d N R ~ _ N ~ £ q c r v LL a oo c m ~ a ~ c E ~ c m ~ a ~ en ~ ~ ti a ~ c it ~+ O t]d'. C} ~ P ~ U ® m 'a U ~ L ~ ~ N ~ ~ ~ a LV - ~I ~ YL L L V] D ~ ~ 61 % O ~ O ~ 7 ~ m W ~ ~ ~ ±D ~ ~ ~ N C R ~ ~ ~ O. ~ ~ ~ J ~ ~ C ~ 4 ~ ~ W e ~ ~ ~ G ~ ~C ~ - -- . ~ J ~ fl. V7 C 0] U U' ^ O ^ LL C'S = T2 ~ D ~ d ~ U ~ d N S U Q y F~ lL ~ w • ~:? o a • v a • a o a •• ~I 9 Q F ~ a m •rr~~ vd L L CCN C O J 7.~ ~ ~ c~ yr ~ ~ m ~ ~_}. Q Q 0 a ~_ N 3 ~3 a a tl3 tea as car c .~ cx. U] L L City of lMnter Springs TMDL Master Plan Estimated Load Reduction FDEP provided existing load estimates using the TMDL pollutant loading model for the proposed tributary area. For the proposed filtration devices, CDM used the median TP removal efficiency of 30 percent for media filters previously cited from the International Stormwater BMP Database [1999-2008] to calculate the proposed net loading. Using FDEP's load estimate for the proposed tributary area provided in Table 22 and Equation 5-3, CDM calculated the proposed net loading: Net Loadingpro = (85.71bs/yr) (1 - 0.3) = 60.0 lbs/ yr Table 22 City of Winter Springs TMDL Master Plan Winter Springs and Wedgewood Subdivisions Proposed Improvements TP Load Reduction Estimates Proposed FDEP Gross TP Reduction FDEP Net Proposed Net Estimated TP Tributary Area TP Load due to Existing TP Load TP Loading Load Reduction (ac) (Ibs) BMPs (Ibs) (Ibs) (Ibs/yr) (Ibs/yr) 489.2 (filtration) 104.9 19.2 85.7 60.0 25.7 5.4 Little Lake Howell Subbasin 5.4.1 Oak Forest Unit 2A, 2B & 3 With the exception of underdrains, Units 2A, 2B and 3 of the Oak Forest subdivision do not have stormwater treatment in place, as shown in Figure 43. These areas discharge directly into the tributaries of the Little Lake Howell primary stormwater management system (PSMS). The City may want to consider retrofitting the underdrain outfalls with end of pipe treatment such as flow-through off-line filtration devices; however, there exist no easements along these tributaries and residential properties are immediately adjacent to these areas. Stormwater retrofit in this area may not be as critical as some of the other areas because the overflow from the Little Lake Howell PSMS flows through a large wetland system to the north towards Lake Jesup. Recommendations Based on this conceptual analysis, CDM recommends the following: ^ Explore the feasibility of obtaining an easement behind residents in order to equip existing outfall with flow-through off-line filtration devices; and ^ Retrofit the six existing stormwater outfalls to the Little Lake Howell tributaries with flow-through off-line filtration devices. ~~ 77 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx o e o - a, w ~ a ;` m LL G ~ t d ~ 3 C ~ ~ ~ ^ E ~ C ~ C ~ Q GS V j Sn N' ~ ~ ~ kL 0 4--6 m ~ N V N N ~ d W 3 m~ U€ 9~ m~ m m~ c `m o d i~ a m® ~i V] ~ m CT U ^ O ^ ti i7 Y ~ ~ © ~ H U 5 a G7 ~ b ., i ~~ r.. 'e ~ ~~ ., <- d ~'~ ~. 1 1 ~~ ~`6 ca ~ tC1 V '.i..l z ~~ ~~ ~~~ ~_~~ City of lMnter Springs TMDL Master Plan Estimated Load Reduction FDEP provided existing load estimates using the TMDL pollutant loading model for the proposed tributary area. For the proposed filtration devices, CDM used the median TP removal efficiency of 30 percent for media filters previously cited from the International stormwater BMP Database [1999-2008] to calculate the proposed net loading. Using FDEP's load estimate for the proposed tributary area provided in Table 23 and Equation 5-3, CDM calculated the proposed net loading: Net Loadingpro = (18.1 lbs/yr) (1 - 0.3) = 12.71bs/ yr Table 23 Winter Springs TMDL Master Plan Winter Springs and Wedgewood Subdivisions Proposed Improvements TP Load Reduction Estimates Proposed FDEP Gross TP Reduction FDEP Net TP Proposed Net Estimated TP Load Tributary Area TP Load (Ibs) due to Existing Load (Ibs) TP Loading Reduction (ac) gMPs (Ibs) (Ibs/yr) Ibs/ r 44.8 (filtration) 21.5 3.4 18.1 12.7 5.4 6.0 Recommended Non-Structural Pollutant Load Reduction Strategies The BMAP also requires that future growth is addressed. Future growth is typically addressed through an entity's long term planning (i.e., Comprehensive Plan) and policies. The following paragraphs describe a number ofnon-structural practices, although to date have not been quantified in terms of pollutant load reduction, that when implemented can help reduce the impact of future growth as it related to nonpoint source runoff. 6.1 Low Impact Development Practices The City may want to consider requiring new development to incorporate more low impact development (LID) practices. Through the City's Comprehensive Code, Code of Ordinances and the MS4 NPDES permit, several practices are already required such as upland buffers for wetlands, protecting environmentally sensitive features increasing infiltration, and education and outreach. The Center for Watershed Protection (CWP) convened a roundtable in the late 1990s to develop a set of model development principles for consideration by local planners, developers, lenders and environmental groups. Applied together, the model principles can measurably reduce impervious cover, conserve natural areas and prevent stormwater pollution from new development (CWP, 2001) and CDM has evaluated and recommended LID practices in stormwater master plans since the 1980s. These development principles are not national design standards but instead identify areas where existing codes and standards can be changed to better protect streams, lakes and wetlands at the local level. The development principles have been grouped into three major categories: ~~ 79 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of lMnter Springs TMDL Master Plan ^ Residential Streets and Parking Lots ^ Lot Development ^ Conservation of Natural Areas The development principles under each of these categories are summarized in Table 24. Table 24 City of Winter Springs TMDL Master Plan LID Development Principles Residenti al Streets and Parking Lots 1. Design residential streets for the minimum required pavement width needed to support travel lanes; on-street parking; and emergency, maintenance, and service vehicle access. These widths should be based on traffic volume. 2. Reduce the total length of residential streets by examining alternative street layouts to determine the best option for increasing the number of homes per unit length. 3. Wherever possible, residential street right-of-way widths should reflect the minimum required to accommodate the travel-way, the sidewalk, and vegetated open channels (i.e., swales). Utilities and storm drains should be located within the pavement section of the right-of-way wherever feasible. 4. Minimize the number of residential street cul-de-sacs and incorporate landscaped areas to reduce their impervious cover. The radius of cul-de-sacs should be the minimum required to accommodate emergency and maintenance vehicles. Alternative turnarounds should be considered. 5. Where density, topography, soils, and slope permit, vegetated open channels should be used in the street right-of-way to convey and treat stormwater runoff. 6. The required parking ratio governing a particular land use or activity should be enforced as both a maximum and a minimum in order to curb excess parking space construction. Existing parking ratios should be reviewed for conformance taking into account local and national experience to see if lower ratios are warranted and feasible. 7. Parking codes should be revised to lower parking requirements where mass transit is available or enforceable shared parking arrangements are made. 8. Reduce the overall imperviousness associated with parking lots by providing compact car spaces, minimizing stall dimensions, incorporating efficient parking lanes, and using pervious materials in the spillover parking areas. 9. Provide meaningful incentives to encourage structured and shared parking to make it more economically viable. 10. Wherever possible, provide stormwater treatment for parking lot runoff using landscape swales, bioretention areas, filter strips, and/or other practices that can be integrated into required landscaping areas and traffic islands. Lot Development 11. Advocate open space development that incorporates smaller lot sizes to minimize total impervious area, reduce total construction costs, conserve natural areas (i.e., reduced ~~ 80 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of lMnter Springs TMDL Master Plan Table 24 City of Winter Springs TMDL Master Plan LID Development Principles clearing of trees), provide community recreational space, and promote watershed protection. 12. Relax side yard setbacks and allow narrower frontages to reduce total road length in the community and overall site imperviousness. Relax front setback requirements to minimize driveway lengths and reduce overall lot imperviousness. 13. Reduce overall lot imperviousness by reducing site clearing, promoting alternative driveway surfaces and shared driveways that connect two or more homes together. 14. Clearly specify how community open space will be managed and designate a sustainable legal entity responsible for managing both natural and recreational open space. 15. Direct rooftop runoff to pervious areas such as yards, open channels, or vegetated areas and avoid routing rooftop runoff to the roadway and the stormwater conveyance system. Conservation of Natural Areas 16. Create a variable width, naturally vegetated buffer system (e.g., landscaped swale) along all perennial streams that also encompasses critical environmental features such as the 100-year floodplain, steep slopes and freshwater wetlands. 17. The riparian stream buffer should be preserved or restored with native vegetation that can be maintained throughout the plan review, delineation, construction, and occupancy stages of development. 18. Clearing and grading of forests and native vegetation at a site should be limited to the minimum amount needed to build lots, allow access, and provide fire protection. A fixed portion of any community open space should be managed as protected green space in a consolidated manner. 19. Conserve trees and other vegetation at each site by planting additional vegetation, clustering tree areas, and promoting the use of native plants. Wherever practical, manage community open space, street rights-of-way, parking lot islands, and other landscaped areas to promote natural vegetation. 20. Incentives and flexibility in the form of density compensation, buffer averaging, property tax reduction, stormwater credits, and open space development should be encouraged to promote conservation of stream buffers, forests, meadows, and other areas of environmental value. In addition, off-site mitigation consistent with locally adopted watershed plans should be encouraged. 21. New stormwater outfalls should not discharge unmanaged stormwater into jurisdictional wetlands, sole-source aquifers, or other water bodies. Source: Consensus Agreement on Model Development Principles to Protect Our Streams, Lakes and Wetlands. CWP, 1998.; City of Jacksonville stormwater Master Plan (CDM, 1992); Big Creek Water Resources Management Plan (CDM, 2001) ~~ 81 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of Winter Springs TMDL Master Plan In addition to the development principles listed above, other LID principles can include: ^ Incorporation of small-scale stormwater treatment systems integrated at the lot level; ^ Increasing infiltration; ^ Green roofs; ^ Pervious pavement; ^ Florida friendly landscaping; ^ Lakeshore protection; and ^ Education & outreach. 6.2 Redevelopment The City's land development code currently requires stormwater management for new development; however it is not specific to redevelopment. In addition to the economic and social benefits that successful redevelopment projects provide, they also afford an opportunity to incorporate stormwater management techniques and practices, which may have not previously existed or were substandard, which in the long term can provide better overall protection to the watershed. The following paragraphs provides examples of stormwater practices that can be used as guidance that when implemented at the local level, will help reduce pollutants in runoff, improve stormwater management and improve the environmental quality of development sites in highly urbanized watersheds. The CWP convened a Redevelopment Roundtable, which consisted of national and local stakeholders who participated in the process to develop "Smart Site Practices" specifically for redevelopment and infill sites. These practices are documented in the Redevelopment Roundtable Consensus Agreement, Smart Site Practices for Redevelopment and Infill Projects (CWP, 2001). When applied together, these practices provide benefits for all local stakeholders including developers, local government residents and others who are interested in designing redevelopment so that it better protects the local watershed features such as streams, lakes, wetlands and estuaries. Examples of redevelopment projects include historic preservation, waterfront development, Brownsfields, residential infill, adaptive reuse, downtown business district, multifamily, suburban commercial, mixed use development and roadway expansion. The "Smart Practices" were developed as a tool to be used by developers, local government and planners and can be utilized to develop better criteria on which to gauge the potential impact of a development site. The practices are generally described below: Practice No. 1: Redevelopment and infill planning should include environmental site assessments that protect existing natural resources and identify opportunities for restoration where feasible. ~~ 82 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of Winter Springs TMDL Master Plan ^ Practice No. 2: Sites should be designed to use impervious cover efficiently and to minimize stormwater runoff. Where possible, the amount of impervious cover should be reduced or kept the same. In situations where impervious cover does increase, sites should be designed to improve the quality of stormwater runoff at the site or in the local watershed. ^ Practice No. 3: Plan and design sites to preserve naturally vegetated areas and to encourage revegetation, soil restoration and the utilization of native or non- invasive plants where feasible. ^ Practice No. 4: Establish mechanisms to guarantee long-term management and maintenance of all vegetated areas. ^ Practice No. 5: Manage rooftop runoff through storage, reuse, and/or redirection to pervious surfaces for stormwater management and other environmental benefits. ^ Practice No. 6: Parking lots, especially surface lots, should be minimized and designed to reduce, store and treat stormwater runoff. Where site limitations or other constraints prevent full management of parking lot runoff, designers should target high-use areas first. ^ Practice No. 7: Utilize a combination of Better Site Design techniques with infill projects to minimize stormwater runoff and maximize vegetated areas. Many single lot or small multi-lot infill projects contribute to "impervious creep;' which is defined as the increase uz impervious cover seen over time in highly developed areas. On-site improvements, such as house additions, expanded driveways, new housing, and sidewalks all contribute to impervious creep. Better Site Design refers to a design approach that seeks to reduce the amount of impervious cover associated with development, increase the natural lands set aside for conservation, use pervious areas for more effective stormwater treatment, and achieve a marketable, cost-effective product. Better Site Design consists of a series of benchmarks that fall under three categories: parking lot and street design, lot development, and natural areas conservation. ^ Practice No. 8: Use proper storage, handling and site design techniques to avoid the contact of pollutants with stormwater runoff. ^ Practice No. 9: Design the streetscape to minimize, capture and reuse stormwater runoff. Where possible, provide planting spaces to promote the growth of healthy street trees while capturing and treating stormwater runoff. In arid climates, xeriscape or water wise landscaping should be used to achieve similar benefits. ^ Practice No. 10: Design courtyards, plazas, and amenity open space to store, filter or treat rainfall. ^ Practice No. 11: Design sites to maximize transportation choices in order to reduce pollution and improve air and water quality. ~~ 83 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of Winter Springs TMDL Master Plan 6.3 Fertilizer Ordinance The Florida Consumer Fertilizer Task Force was created by the Florida Legislature in 2007 to review and provide recommendations on the state's policies and programs addressing consumer fertilizers. One of the key recommendations adopted by the Task Force that is described in the Florida Department of Agriculture and Consumer Services Florida Consumer Fertilizer Task Force Final Report to the 2008 Florida Legislature (Blair et. al., 2008) included a model ordinance concerning the use of nonagricultural fertilizer for use by local governments who choose to adopt an ordinance as directed by the Legislature. The Task Force recommended that local governments can adopt more stringent provisions to the model ordinance provided the local government can demonstrate they meet at least one of the following criteria: 1. They have verified impaired waters and are facing existing or possible TMDL requirements (under state and federal laws); or; 2. They have verified harm to human health or harm to the environment that warrants additional consumer fertilizer requirements; or 3. That they will improve water quality or prevent future impacts of consumer fertilizers on the environment. Several communities throughout Florida have either adopted or are moving toward developing fertilizer ordinance that restricts the use of commercial and residential fertilizers. Sarasota County's recently adopted ordinance, now one of the strictest within the State, contains the following provisions: ^ Homeowners and business owners are forbidden from using chemical fertilizers during the rainy season; ^ Sets maximum levels for nitrogen and phosphorus; and ^ Creates a 10-foot "fertilizer-free zone" near bodies of water. Although it is still relatively early to realize the benefits and challenges of implementing such an ordinance, the City has also expressed interest in developing one. A model ordinance can be found on FDEP's website at: http: / /www.dep.state.fl.us/water/nonpoint/pubs.htm#Model%200rdinances 6.4 Golf Courses BMPs There are a number of management activities outlined in the Best Management Practices for the Enhancement of Environmental Quality on Florida Golf Courses (FDEP, 2007) that can be implemented to help reduce nonpoint source runoff to surrounding waterways including irrigation, fertilization, cultural practices (i.e. mowing, cultivation), lake and aquatic plant management, turfgrass pest management, pesticides and maintenance. ~~ 84 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of lMnter Springs TMDL Master Plan 7.0 Pollutant Load Summary The estimated pollutant load reductions associated with projects and activities discussed in this report have been summarized below in Table 25. Based on the activities and projects outlined in this report, it is apparent that the recommendations made with quantified estimates can address the remaining reduction for the Phase II allocation (242.41bs) of the total TP reduchon required by FDEP and a portion of the remaining reduction for the Phase III allocation. Table 25 City of Winter Springs TMDL Master Plan Summary of Estimated TP Removal Activity/Project Estimated TP Reduction (I bs/yr) Highlands Subdivision Pond Improvements 64.5 Buttonwood Avenue Stormwater Facility and Filtration Devices g.4 Hacienda Village Stormwater Facility and Filtration Devices 3.5 N. Orlando Ranches & Winding Hollow Subdivision Wetland Treatment Area 201.7 North Orlando Townsite Subdivision Filtration Devices 5.2 Tuscawilla Country Club Stormwater Reuse 2g.g Tuscawilla Country Club Golf Course Water Features 3.7 Winter Springs Boulevard Pond Enhancements 1.5 Winter Springs and Wedgewood Subdivisions Filtration Devices 25.7 Oak Forest Units 2A, 2B & 3 Filtration Devices 5.4 Street Sweeping 7.3 Total Estimated Reduction for Proposed Projects 357.7 Other Activities/Projects Outside of TMDL Master Plan Estimated TP Reduction (I bs/yr) Florida Yards & Neighborhoods 80.5 Local Codes and Ordinances 34.5 Solary Canal Regional Stormwater Treatment Area 314.0 Total Estimated Reduction for Proposed Projects and Non-Master Plan Projects 788.7 Total Reduction Needed to Meet Phase I Allocation (as per FDEP, February 2009) 0.0 Documented BMP Load Reductions (as per FDEP, February 2009) 786.4 Remaining Reduction Needed to Meet Phase II Allocation (as per FDEP, February 2009) 241.3 Remaining Reduction Needed to Meet Phase III Allocation (as per FDEP, February 2009) 513.9 ~~ 85 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of lMnter Springs TMDL Master Plan 8.0 Recommended Project Ranking and Prioritization To assist the City with implementation, CDM has developed a prioritized list of conceptual stormwater improvements based upon the results of this TMDL Master Plan. The remainder of this section provides a discussion on project prioritization criteria and the results of the application of these criteria to the identified improvements. It should be noted that this list is only a tool for project planning and should not be considered absolute. Recommended improvements are conceptual in nature. 8.1 Estimated Alternative Costs Conceptual cost estimates were developed for the alternative improvements described in Section 5. A summary of the conceptual planning level cost by project is provided in Table 26. A detailed breakdown of cost by item is provided in Attachment 2. Table 26 City of Winter Springs TMDL Master Plan Estimated Capital Improvement Costs Major Subbasin Description Estimated Cost Soldiers Creek Highlands Subdivision Pond Improvements $1,385,000 Gee Creek Buttonwood Avenue stormwater Facility and Filtration $3 613 000 Devices , , Gee Creek Hacienda Village stormwater Facility and Filtration $1 276 000 Devices , , Gee Creek/Little N. Orlando Ranches & Winding Hollow Subdivision $357 000 Lake Howell Wetland Treatment Area , Gee Creek North Orlando Townsite Subdivision Filtration Devices $80,000 Howell Creek Tuscawilla Country Club stormwater Reuse $499,000 Howell Creek Tuscawilla Country Club Golf Course Water Features $993,000 Howell Creek Winter Springs Boulevard Pond Enhancements $250,000 Howell Creek Winter Springs and Wedgewood Subdivisions Filtration $194 000 Devices , Little Lake Oak Forest Units 2A 2B & 3 Filtration Devices $194,000 Howell , Total $8,841,000 8.2 Development of Ranking Criteria The preliminary ranking of stormwater problem areas was developed using an assessment criteria-screening matrix. The City reviewed the ranking criteria and provided feedback. The criteria used to rank the recommended projects are: ^ Construction Cost per lb of TP Removal ^ Flood Benefit ^ Permittability ^ Ease of Maintenance ~~ 86 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of lMnter Springs TMDL Master Plan The typical evaluation for each recommended project included assigning a value (0- 10) to each criterion. These values are based on information collected during the development of the TMDL Master Plan and are intended only to assist in defining priorities. As more detailed information becomes available, these criteria should be re- evaluated and priorities should be redefined accordingly. Values for each criterion are based on the following: Construction Cost per lb of TP Removal This criterion is related to the potential enhancement of water quality and the associated costs. As a detailed benefit cost analysis is beyond the scope of services, CDM estimated the cost per lb of TP removal using a standard design life for the types of stormwater facilities recommended. For wet detention facilities and filtration devices, CDM used a design life of 50 and 25 years, respectively. Based on this approach, the cost per lb of TP removed is provided below in Table 27. A value of 0 represents the project with the highest cost per lb of TP removed while a value of 10 represents the lowest cost per lb of TP removed. Using the difference between the lowest and highest cost per lb of TP removed, CDM assigned scores for the remaining projects based on a proportion. Table 27 City of Winter Springs TMDL Master Plan Estimated Cost er lb of TP Removal Design Facility Cost/Ib TP Description Estimated Cost Life Cost per Removed (years) Year' ($) ($/Ib) Highlands Subdivision Pond Improvements $1,385,000 50 $27,700 $429 Buttonwood Avenue stormwater Facility $3 613 000 50 $72 260 $7 687 and Filtration Devices , , , , Hacienda Village stormwater Facility and $1 276 000 50 $25 520 $7 291 Filtration Devices , , , , N. Orlando Ranches & Winding Hollow $357 000 50 $7 140 $35 Subdivision Wetland Treatment Area , , North Orlando Townsite Subdivision $80 000 25 $3 200 $615 Filtration Devices , , Tuscawilla Country Club stormwater $499 000 25 $19 960 $670 Reuse , , Tuscawilla Country Club Golf Course $883 000 50 $19 860 $5 368 Water Features , , , Winter Springs Boulevard Pond $250 000 50 $5 000 $3 333 Enhancements , , , Winter Springs and Wedgewood $194 000 25 $7 760 $330 Subdivisions Filtration Devices , , Oak Forest Units 2A, 2B & 3 Filtration $194 000 25 $7 760 $1 437 Devices , , , 1. Does not include annual operation and maintenance costs ~~ 87 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of Winter Springs TMDL Master Plan Flood Benefit The flooding criterion is based on the ability of the recommended project to provide any relief for known flooding problems in the vicinity. The City provided information on recent flooding due to Tropical Storm Fay that occurred in August, 2008. Where applicable, CDM attempted to incorporate flood control benefits into the water quality improvement projects. A value of 0 is given to represent either no flooding or the project does not provide flood control benefits. A value of 5 represents some anticipated flood relief and/or provides additional storage capacity based on the projects proposed, and a value of 10 represents substantial flood relief based on the project recommended. As detailed hydrologic and hydraulic modeling were not performed, scores for this criterion were assigned on a qualitative basis. Permittability Permittability refers to the ability of the identified project to be permitted under current regulatory constraints. An unpermittable project would be assigned a 0. A value of 5 represents that a permit could potentially be obtained. A value of 10 would represent an easily permittable or exempt situation. A project that would require significant dredging in wetlands would be considered unpermittable. Ease of Maintenance This criterion is related to the level of maintenance needed to keep the facility in good working order. A value of 5 represents a moderate level of maintenance is needed as in the case of a baffle box that needs to be cleaned with a "vac truck" on a regular basis. A value of 10 would represent a lower level of maintenance such as culvert cleaning which would require less expensive equipment and would need to occur less frequently. Criteria Weighting Each of the criteria noted above have been assigned a "weight" that is based on the value of the criterion. That is, one criterion may be more important to the County than another. The value assigned to each criterion is multiplied by the "weight" of the criterion and summed to determine the accumulative score for each problem area. The weights assigned to each criterion are as follows: Criterion Weight Construction Cost/lb TP Removal 7.0 Flood Benefit 1.0 Ease of Maintenance 1.0 Permittability 1.0 CDM assigned scores for each of the individual projects based on the criteria discussed above. The projects were then ranked based on the total score for each project. The results of the ranking are provided in Table 28. ~~ 88 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx ~i O N O r--I Y .^ m F-I Y ~ ~ O1 (n Fy v N N ~I 3~~ O Q U H U Y ~ ~ N M V Ln CO I~ CO O) ~ i ~ V CO CO CO CO ~ I~ COO V N ~ y d ~a o ~ ~ ~ 0 0 0 ~ ~ ~ ~ ° co co co . ., N G d J.~~ O ~ ~ O ~ O O Ln O O M ~ ~ a `0 r t 3 d e d m O r M O M O O Cp Cp CO M a 0 0 ti e ,~ 0 O i p ~ Q O ~ r~r N ~. O n CO O) ~ I~ O N O N O N CO ~ Ln O M O O Ln O ~ Q d O y ~ U O U ~ r ~ ~ ° a°i ~ ~ > o r Y .- a ~ a ~ O ° ~ > O L y~ E L j Y~ to C O ~ N °- T O .E (6 C N '~ a N Y '~ ~ N (6 ~ L Y O N Y~ -_ >i N Q >i a Q~~ w 9 N C N ~ O ~~ N L ~ ~ 0 U O ~ J C_ ' > ~ N O ~ Y O O Z CJ O y p T y - ~ a Y U ~ - N j/1 to O L N O N O y a a Y y C C ~~ (6 O o C~ N Q C !6 N p- a 0 y~ a C ~ y0 0 + -' J N N O N a > t/1 ~ Y Y (6 .~ ~ `p ~ (6 Q p . !6 X (p -p N L Z O S a w C p p Y N~ y Q L Y N (~ - N m ?~ a~ ~ °- O C p ~ 9 O L (h -_ a to ~ C y O 0 9 ~ z ~ ~ Q~ L ~ O f/) >j C ~'"' C _ N O` O C Q y0 ~ ~ !6 ~ ~ p 9 y (6 U t/1 C N ~~ C ~ ~ O p N E (6 a O ~ ~ C y ~ ~ t/1 ~ U (6 > p T'_ (6 C N N O : O S C°~ 0 0 a C ~~ U ~ a tp/1 C O a ~ y O (6 ~ C y O 9 C T -_ !6 ~ N O (6 p O ~ C !6 O !6 'p N ° a O C - t/1 . t/1 (6 p p U O ~ y N Y C° to a > 9 a a > p- C C L O C y O a C~ U O ~ N C C O D C (6 ~ ~ . a- ~ O ~ .O ~ to ` C N U f/) N f0/) O i _T 9~ y~ 0 O ,C ~~ N 00 O ~ N -O '~ > ~ C L ~ f/) ~ a N ~ - ~ -O CO ~ 'p ~ C O Y ~ ~ >j N C w O a ` a .~ a ~6 a 9 a ~6 ~ O U C N o rn N ~ L o ~ (C6 O C o !6 w rn - O U C O a C - m' ~ o a 0~ rn ~ a o~ L °~ '~ 9 ~' ~~ ~ ~ o > o a ~ `~ o a 5 a o ~ °~ p a o~~ i ' ~~ E °-o aim a~ Q ~ ~y~~ Tai ° ca a9 ~= m ~Y ° ° c0 'L-' o my n ~ Q~ ° oa o ~ o Q = ° 0 0 . ~ ° o ~ rn Y ~ ° ° ~ in o ~' ~' ° ° . o ~ Q~ m o o ~ ~ a Q -O m ~ -O X .. rn m . ~ o L ~X U y 0 ~ ~ a i M S N O N f/1 ~ ~ m .-. O (6 C ~ ' - ~ (6 X N ~ a ~ C _O U O ~ ~ o ~ O p O N o L O N~ N' p N T N O a t E y C~ j jp O~ X w ~ L y t/1 t/1 !6 -' N w X L t/1 ' ~ !6 !6 ~ a -O N •~ >i O O 'C N L O V ~ a~ a ~ N p O ,L...X w a p y -O ~ p~ C -O C ~ Y~ N a Y y Y~ X ~ N (6 O ~ y y ~ C ~` (6 ~~ X>~ !6 U p y 0 ~ Y Y V y t0/1 y O C ' w ~ ~ ~ (6 a ~ a C N .-. ~ - ~ Q N ~ ._ ~ .-. ~ - !6 p 0 ~ ~ O N ` Z ~ Q ~ 0 ~ ~ O U (6 !6 N C a a C U O (6 N -_ T N Y ~p (6 L y ~ a ~' f/1 N N N Y O ~i N > N C j O O~ N O y6 O O N 9 > ~ .C !6 ~ p U U .~ O~ Q ~ O Q ° p ~ - y6 f/1 N L C y D a 0~ O 9 O f/1 C N L_ O N O C E a Q C C d' O O .C >i !6 .L.. p d' w U ~ d' f/1 d' .`. X U X N W (6 N ~ Q (p C U p U O ~ Q... Z . C~ C~ >i G y ~ ~ N Y Y ~ Y Y U N N CJ N CJ N = N CJ N CJ N N ~ ~ U U Y U U i' =p N ~ ~ N J ~ ~ N N W In ~ S S (7 0 = _ C7 (7 J C N C O rn C N ~ C C C '~ p ~ 9 j 9 C CO d 9 d ~ O Q W - ~> -o (~ ~ ~~ -o (~ ~ ~ C o O ~ ~ ~ C ~ ~ a ~ ~ ~ C N 6 ~ O ~ 9 p m ~ ! E v O O m> U o ~ CJ ° ~ ~> S ~9 ~ O N ~L ~ > (n V a O ~ ~ a ° W ° Q W ~ Q N 1 9 C - (n U ~ (C6 Y Cn U ~ a O O ~ O ~ a (n ~ a 0 ° ~ ° ~ p ~ O (6 O ~ p ~ p ~ -_ > ~ ~ ~ O ~ o ~ -Oo C L 01 Z m N U S O S City of Winter Springs TMDL Master Plan 9.0 Summary and Conclusions Based on the ranking shown in Table 28, the Highlands Subdivision pond enhancement and the Winding Hollow Subdivision wetland rehydration project were the top ranked projects with the total scores only differing by a point. The City will receive credit for the Solary Canal Regional stormwater Treatment Area (designed by others) as well as education and Florida Yards and Neighborhood programs that will help fulfill the remainder of the City's Phase II allocation. Based on the load reduction estimates presented in this report, implementation of both the Highlands Subdivision pond enhancement and the Winding Hollow Subdivision wetland rehydration projects would help fulfill the City's Phase III allocation in its entirety. It is also important to note that Winding Hollow Subdivision wetland rehydration project would treat area in addition to what is within City limits (as well as provide additional load reduction other than what is reported for just the City), as shown in Figure 44. The total estimated tributary to the proposed facility is approximately 2,810 acres. There may be some opportunity for regional participation as a large portion of the upstream area is within unincorporated Seminole County. Some projects that were recommended may also provide additional TP load removal currently not recognized by the FDEP TMDL pollutant load model. One such example is the Tuscawilla Country Club project. By implementing stormwater reuse, the pollutant load model can recognize the benefit of this project by increasing the treatment efficiency of the surrounding wet detention ponds. However benefits that are not currently recognized by the model include the reduction of reclaimed water on the golf course by using stormwater for irrigation. The model currently does not account for potential TP loads due to the site-specific mismanagement (i.e., overuse) of reclaimed water. In other instances, projects were recommended to provide surface water treatment, but they also have the capability to capture flow from underdrains that currently discharge directly into the MS4 and constitute base flow (e.g., Highlands Subdivision, Winding Hollow Subdivision). Although FDEP's TMDL modeling did account for base flow, FDEP considered it to be an uncontrollable source and therefore did not give credit to activities or projects that may be reducing the concentration in baseflow in the tributaries to Lake Jesup. As the TMDL pollutant load model is refined over time, it is anticipated that some of the aforementioned examples that provide treatment to pollutant sources currently not recognized in the model will receive credit in future iterations of the BMAP. The contributions of these pollutant sources need to be better quantified and agreed upon by Lake Jesup BMAP Stakeholders so that proper credit can be given for projects implemented. The load reductions presented in Table 25 are relatively low (less than 251bs/year for most projects) and the estimated capital costs for construction may seem high for the benefit received. However, in order to gage the true benefit received, the life cycle cost of the project should be calculated and then compared to the removal (lbs/yr) in order to develop acost-to-benefit ratio for each project. Life cycle costs are all the costs ~~ 90 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx ~ ~ ~ ~ ~Q ~~ ~~ s~ w a E 0 rz v c a .~ .~ a vi a 0 w c v c s s.~ ~s 0 c Z City of Winter Springs TMDL Master Plan that occur during the life time of the stormwater control device. It includes design, construction, operation and maintenance, and closeout activities. Life cycle costs include the initial capital cost and the present worth of annual O&M costs that are incurred over time, less the present worth of the salvage value at the end of the service life (Sample, et al., 2003). In general, it appears that the projects that capture and treat flows diverted directly from the creeks provide a far greater treatment capability than conventional stormwater retrofits. The tributary areas on individual retrofit projects are not large enough to generate TP loads that justify the costly retrofits. With this in mind, it appears that over the long term the City should pursue projects that divert and treat flows from Howell, Gee, and Bear Creeks. 10.0. References Brown, W. 1998. The Site Planning Roundtable: Technical Support Document. Center for Watershed Protection, Ellicott City, MD. Brown, W. and T. Schueler. 1997. National Pollutant Removal Performance Database for stormwater Best Management Practices. Center for Watershed Protection, Ellicott City, MD. Center for Watershed Protection. 2001. Redevelopment Roundtable Consensus Agreement, Smart Site Practices for Redevelopment and Infill Projects. Gao, X. 2006. TMDL Report. Nutrient and Unionized Ammonia TMDLs for Lake Jesup, WBIDs 2981 and 2981A. Florida Department of Environmental Protection. Guidelines for Water Reuse. 2004. U.S. Environmental Protection Agency. Harper, H.H., J.L. Herr, D. Baker, and E.H. Livingston. 1999. Performance Evaluation of Dry Detention stormwater Management Systems. Sixth Biennial stormwater Research h Watershed Management Conference. Hunt, W.F. and B.A. Doll. 2000. Designing stormwater Wetlands for Small Watersheds. North Carolina Cooperative Extension Service. International stormwater BMP Database www.bmpdatabase.org Kadlec, R.H. and Wallace, S.D. (2009). Treatment Wetlands. (2nd Addition). Fort Lauderdale, Fl: CRC Press. Sample, D.J., J.P.Heaney, L.T.Wright, C.Y.Fan, F.H.Lai, and R.Field. 2003. Cost of Best Management Practices and Associated Land for Urban stormwater Control. Journal of Water Resources Planning and Management, Vol. 129, No.1, pp. 59-68. ~~ 92 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx City of Winter Springs TMDL Master Plan Schueler, T.R. 1992. Design of Stormwater Wetland Systems: Guidelines for Creating Diverse and Effective Stormwater Wetlands in the Mid-Atlantic Region. Anacosta Restoration Team, Department of Environmental Programs, Metropolitan Washington Council of Governments. Strecker, W.E., J.M. Kersnar, and E.D. Driscoll. 1992. The Use of Wetlands for Controlling Stormwater Pollution. Woodward-Clyde Consultants. Prepared for the U.S. Environmental Protection Agency. 61 pp + appendix. Wong, T.H.F., P.F. Breen, N.L.G. Somes, and S.D. Lloyd. 1992. Managing Urban Stormwater Using Constructed Wetlands. Cooperative Research Center (CRC) for Catchment Hydrology Department of Civil Engineering, Monash University, Australia. ~~ 93 S:\65898\63938\Report\Letter Report\Ltr_Rprt.Docx Attachment 1 2'-3 I 4' I 3 /4" 1T WITH PLUG LE 'VC WEIR 'VC BAFFLE CLEAN OUT I PLUG 1-CARTRIDGE CATCHBASIN -SECTION VIEW A 1 TI1E STORM WATER MANAGEMENT StormFilter® U.S. PATENT No. 5,322,629, No. 5,707,527, No. 6,027,639 No. 6,649,048, No. 5,624,576, AND OTHER U.S. AND FOREIGN ©2006 CONTECH Stormwater Solutions PATENTS PENDING DRAWING A~~~~ITCAIJ® CONCRETE CATCHBASIN STORMFILTER iii-~ ~i~~:-! STORMWATER PLAN AND SECTION VIEWS ~ SOLUTIONS~~ 1 CARTRIDGE UNIT -STANDARD DETAIL ,/3 contechstomlwater.com DATE:10/26/05 SCALE: NONE FILE NAME: CBSF1-C-DTL DRAWN: MJW CHECKED:ARG 1-CARTRIDGE CATCHBASIN -PLAN VIEW 1 1 6' 1-CARTRIDGE CATCHBASIN -SECTION VIEW 1-CARTRIDGE CATCHBASIN -SECTION VIEW ©2006 CONTECH Stormwater Solutions 35" ~ 2.9') TI1E STORM WATER MANAGEMENT StormFilter® U.S. PATENT No. 5,322,629, No. 5,707,527, No. 6,027,639 No. 6,649,048, No. 5,624,576, AND OTHER U.S. AND FOREIGN PATENTS PENDING DRAWING A~~~~ITCA^® CONCRETE CATCHBASIN STORMFILTER ~~~~~~~ ~ ~~ ~ ' SECTION VIEWS 2 STORMWATER SOLUTIONS~~ 1 CARTRIDGE UNIT -STANDARD DETAIL 2/9 contechstomlwater.com DATE:10/26/05 SCALE: NONE FILE NAME: CBSF1-C-DTL DRAWN: MJW CHECKED:ARG GENERAL NOTES I) STORMFILTER BY CONTECH STORMWATER SOLUTIONS; PORTLAND, OR (S00) 548-4667; SCARBOROUGH, ME (877) 907-8676; LINTHICUM, MD (866) 740-33 I S. 2) FILTERS TO BE SIPHON-ACTUATED AND SELF-CLEANING. STANDARD DETAIL SHOWS MAXIMUM NUMBER OF CARTRIDGES. EXACT NUMBER REQUIRED TO BE SPECIFIED ON SITE PLANS. 3) INLET AND OUTLET PIPES TO BE GROUTED INTO HOLES PROVIDED. JOINTS TO BE WATER-TIGHT. 4) STORMFILTER REQUIRES BETWEEN 2.75' AND 2.9' OF DROP FROM RIM TO OUTLET. INLET (IF APPLICABLE) AND OUTLET PIPING TO BE SPECIFIED BY ENGINEER AND PROVIDED BY CONTRACTOR. PIPES TO BE GROUTED INTO PROVIDED CORINGS BY CONTRACTOR. 5) ALL STORMFILTERS REQUIRE REGULAR MAINTENANCE. REFER TO OPERATION AND MAINTENANCE GUIDELINES FOR MORE I CARTRIDGE CONCRETE CATCH BASIN STORMFILTER DATA STRUCTURE ID XXX WATER QUALITY FLOW RATE (cfs) X.XX PEAK FLOW RATE (< I cfs) X.XX RETURN PERIOD OF PEAK FLOW (rs) XXX CARTRIDGE FLOW RATE (I 5 OR 7.5 m) XX MEDIA TYPE (CSF, PERLITE, ZPG) XXXXX RIM ELEVATION XXX.XX' PIPE DATA: I.E. MATERIAL DIAMETER INLET XXX.XX' XXX XX" OUTLET XXX.XX' XXX XXX CONFIGURATION OUTLET O INLET OPTIONS (AVAILABLE AT EXTRA COST): ^ HOLE FOR OUTLET STUB OTHER THAN 12" ^ CLEAN-OUT IN WEIR OTHER THAN 4" ^ CORED HOLE FOR INLET PIPE ^ DEEP OUTLET CORING ^ OTHER:XXX 3' I '-6" I '_5" , b A O ~ -~ - 6' ~I 8 d .a w - ~IR - - - dl TI1E STORM WATER MANAGEMENT StormFilter® 1-CARTRIDGE CATCHBASIN -TOP VIEW 1 No. 5,707E527,°No.6027,639 No. 6,649,048, No. 5,624,576, 3 AND OTHER U.S. AND FOREIGN ©2006 CONTECH Stormwater Solutions PATENTS PENDING DRAWING A~~~~ITCAIJ® CONCRETE CATCHBASIN STORMFILTER iii-~ ~i~~:-! STORMWATER TOP VIEW, DATA AND NOTES 3 SOLUTIONS~~ 1 CARTRIDGE UNIT -STANDARD DETAIL 3/3 contechstomlwater.com DATE:10/26/05 SCALE: NONE FILE NAME: CBSF1-C-DTL DRAWN: MJW CHECKED:ARG ATE PIPE ON RTES 5~6) CAST IRON, NON-HINGED 28" x 48" ACCESS HATCH 24" (d FRAME AND COVER (TYP) (SEE NOTE 4) ~~ ~ - A - ~'4. ~. l:u i •ti.. .. : . 18 (lJ TRANSFER ~~ OPENING TO ~' -------------~ FILTRATION BAY f~ 5'-6" MIN °' (SEE NOTE 7) 's. ~ . I '- 10" _ I,~ `~\t / .: DISCHARGE FROM 7' q~_g~~ FILTRATION BAY (lYP) CURB INLET STORMFILTER -SECTION VIEW A TFIESTORMWATERMANAGEMENT 1 StormFilter® U.S. PATENT No. 5,322,629, No. 5,707,527, No. 6,027,639 No. 6,649,048, No. 5,624,576, AND OTHER U.S. AND FOREIGN ©2006 CONTECH Stormwater Solutions PATENTS PENDING DRAWING A~~~~ITCAIJ® 6' x 12' CURB INLET STORMFILTER ~~%-~ ~ir~:7 STORMWATER PLAN AND SECTION VIEWS ~ SOLUTIONS- STANDARD DETAIL ,/3 contechstomlwater.com DATE: 12/12/05 SCALE: NONE FILE NAME: CISF11-612PGDTL DRAWN: MJW CHECKED: ARG CURB INLET STORMFILTER -PLAN VIEW 1 1 FACE PLATE WITH ANCHORS AND SUPPORT 28" x 48" ACCESS CURB AND GUTTER PER BOLT(S) PER CITY HATCH LOCAL STANDARD STANDARD (BY CONTRACTOR) . ~ ; . ~ --_-____ - ...: .p I . ,~ '~ ~. BAFFLE ~. . ~: (5) - 5/8 NC INSERT • ~`^~ ~ WALL STORMFILTER ~' ~- AT 12" O.C. FOR 5/8" CARTRIDGE (TYP) :.~ THREADED ROD OR (SEE NOTE 2) BOLT (TYP) OUTLET .a: . . .a. ~ `. "~ ~,.~ -~ : ~~ ~ ~ : ~ ~ : ~ ' PIPE . . p. - .a~, : ~ .:; ; : :, , INLET BAY UNDERDRAIN FLOOR MANIFOLD CURB INLET STORMFILTER -SECTION VIEW B 2 CAST IRON, NON-HINGED 28" x 48" ACCESS HATCH 12' •°.. •, ~ • s~ `~ ~ .~ ~ : °. " • ~ . .• , ~ j 24" FRAME AN D ~~. • ~ :I: .~~ °' ~ ~.J~ ~• COVER (TYP) .. .;~. :~~~. ... ,. ~.ti;' ~ °~ (SEE NOTE 4) - ~ . • 'r• -I° .. t..~ >. CAST IN PLACE CURB •~ f~. . r • . • ° • (BY CONTRACTOR) '' ~ ~ . ~'°'• "?• ~. ~ ~ •• 'J~{1'~ 1 -. - 6 CAST IN PLACE CURB INLET STORMFILTER -TOP VIEW 1 LOCAL DEPRESSION (BY CONTRACTOR) 2 TF1E STORMWATER MANAGEMENT StormFilter® U.S. PATENT No. 5,322,629, No. 5,707,527, No. 6,027,639 No. 6,649,048, No. 5,624,576, AND OTHER U.S. AND FOREIGN ©2006 CONTECH Stormwater Solutions PATENTS PENDING A~~~~ITCAIJ® ' 12' RB INLET T RMFILTER DRAWING 6 x CU S O TOP AND SECTION VIEWS 2 STORMWATER STANDARD DETAIL SOLUTIONS~~ 2/3 contechstomlwater.com DATE: 12/12/05 SCALE: NONE FILE NAME: CISF11-612PGDTL DRAWN: MJW CHECKED: ARG GENERAL NOTES I) STORMFILTER BY CONTECH STORMWATER SOLUTIONS; PORTLAND, OREGON (800) 548-4667; SCARBOROUGH, ME (877) 907-8676; LINTHICUM, MD (866) 740-3318. 2) FILTER CARTRIDGE(S) TO BE SIPHON-ACTUATED AND SELF-CLEANING. STANDARD DETAIL DRAWING SHOWS MAXIMUM NUMBER OF CARTRIDGES. ACTUAL NUMBER REQUIRED TO BE SPECIFIED ON SITE PLANS OR IN DATA TABLE BELOW. 3) PRECAST VAULT TO BE CONSTRUCTED IN ACCORDANCE WITH ASTM C857 AND C858. DETAIL DRAWING REFLECTS DESIGN INTENT ONLY. ACTUAL DIMENSIONS AND CONFIGURATION OF STRUCTURE WILL BE SHOWN ON PRODUCTION SHOP DRAWING. 4) STRUCTURE AND ACCESS COVERS TO MEET AASHTO H-20 LOAD RATING. 5) INLET AND OUTLET PIPING TO BE SPECIFIED BY ENGINEER AND PROVIDED BY CONTRACTOR. PRECAST STORMFILTER VAULT EQUIPPED WITH EITHER CORED OPENINGS OR KNOCKOUTS AT INLET AND OUTLET LOCATIONS. 6) MAXIMUM CURB INLET OPENING IS 7 FEET. MIRROR IMAGE AVAILABLE. INLET SIDE SPECIFIED IN DATA TABLE BELOW. 7) PROVIDE MINIMUM CLEARANCE FOR MAINTENANCE ACCESS. IF A SHALLOWER SYSTEM IS REQUIRED, CONTACT CONTECH STORM WATER SOLUTIONS FOR OTHER OPTIONS. 8) ANTI-FLOTATION BALLAST TO BE SPECIFIED BY ENGINEER AND PROVIDED BY CONTRACTOR, IF REQUIRED. BALLAST TO BE SET ALONG ENTIRE LENGTH OF BOTH SIDES OF THE STRUCTURE. 9) ALL STORMFILTERS REQUIRE REGULAR MAINTENANCE. REFER TO OPERATION AND MAINTENANCE GUIDELINES FOR MORE INFORMATION. 6' x 12' PRECAST CURB INLET STORMFILTER DATA STRUCTURE ID XXX INLET SIDE (LEFT OR RIGHT) X WATER QUALITY FLOW RATE (cfs) X.XX PEAK FLOW RATE (cfs) X.XX RETURN PERIOD OF PEAK FLOW (rs) XXX # OF CARTRIDGES REQUIRED XX CARTRIDGE FLOW RATE (I 5 OR 7.5 m) XX MEDIA TYPE (CSF, PERLITE, ZPG) XXXXX PIPE DATA: I.E. MATERIAL DIAMETER INLET PIPE XXX.XX' XXX XX" OUTLET PIPE XXX.XX' XXX XX" TOP OF CURB 0 XXX.XX' XXX.XX' WEIR CREST ELEVATION XXX.XX' HEAD OVER WEIR, H (ft) X.XX' WSE at Q eak XXX.XX' ANTI-FLOTATION BALLAST WIDTH HEIGHT XX" XX" NOTES/SPECIAL REQUIREMENTS: ©2006 CONTECH Stormwater Solutions TF1E STORMWATER MANAGEMENT StormFilter® U.S. PATENT No. 5,322,629, No. 5,707,527, No. 6,027,639 No. 6,649,048, No. 5,624,576, AND OTHER U.S. AND FOREIGN PATENTS PENDING UIiAWIN(i A~~~~ITCAIJ® 6' x 12' CURB INLET STORMFILTER ~~%-~ ~ir~:7 STORMWATER NOTES AND DATA 3 SOLUTIONS~~ STANDARD DETAIL 3/3 contechstormwater.com DATE: 12/12/05 SCALE: NONE FILE NAME: CISF11-612PGDTL DRAWN: MJW CHECKED: ARG 42 INLET P (SEE NOTES 5 ~ MANHOLE STORMFILTER -PLAN VIEW 1 1 30"O FRAME AND COVER {STD) CONCRETE (SEE NOTE 4) GRADE RING STEP {TYP) a.,~ INLET PIPE ~ ~ HDPE OUTLET (SEE NOTES 5 ~ 6) RISER WITH SCUM BAFFLE 4'-6" MIN ~ (SEE NOTE 7) STORM FILTER CARTRIDGE (TYP) (SEE NOTE 2) BALLAST {5EE NOTE 8) HEIGHT ~ ~ f• ~:? a ~~ ~ WIDTH UNDERDRAIN SEE DETAIL 2/2 MANIFOLD MANHOLE STORMFILTER -SECTION VIEW ~A UTLET °556) ~~ THESTORMWATER MANAGEMENT StormFilter® U.S. PATENT No. 5,322,629, No. 5,707,527, No. 6,027,639 No. 6,649,048, No. 5,624,576, AND OTHER U.S. AND FOREIGN ©2006 CONTECH Stol'mwater Solutions PATENTS PENDING A~~~~ITCALI® PRECAST 48" MANHOLE STORMFILTER DRAWING ~.1' ~` ~ `~ r~ STORMWATER PLAN AND SECTION VIEWS ~ SOLUTIONS~~ STANDARD DETAIL ~~ contechstormwater.com DATE:09Y16/05 SCALE: NONE FILE NAME: MHSF3-48PC-DTL DRAWN: MJW CHECKED:ARG GENERAL NOTES I) STORMFILTER BY CONTECH STORM WATER SOLUTIONS; PORTLAND, OR (800) 548-4667; SCARBOROUGH, ME (877) 907-8676; ELKRIDGE, MD (866) 740-3318. 2) FILTER CARTRIDGE{5) TO BE SIPHON-ACTUATED AND SELF-CLEANING. STANDARD DETAIL SHOWS MAXIMUM NUMBER OF CARTRIDGES. ACTUAL NUMBER REQUIRED TO BE SPECIFIED ON SITE PLANS OR IN DATA TABLE BELOW. 3) PRECAST MANHOLE STRUCTURE TO BE CONSTRUCTED IN ACCORDANCE WITH ASTM C478. DETAIL REFLECTS DESIGN INTENT ONLY. ACTUAL DIMENSIONS AND CONFIGURATION OF STRUCTURE WILL BE SHOWN ON PRODUCTION SHOP DRAWING. 4) STRUCTURE AND ACCESS COVERS TO MEET AASHTO H-20 LOAD RATING. 5) STORMFILTER REQUIRES 2.3 FEET OF DROP FROM INLET TO OUTLET. IF LESS DROP IS AVAILABLE, CONTACT CONTECH STORM WATER SOLUTIONS. MINIMUM ANGLE BETWEEN INLET AND OUTLET IS 45°. 6) INLET PIPING TO BE SPECIFIED BY ENGINEER AND PROVIDED BY CONTRACTOR. PRECAST MANHOLE STORMFILTER EQUIPPED WITH A DUAL DIAMETER HDPE OUTLET STUB AND SAND COLLAR. EIGHT INCH DIAMETER OUTLET SECTION MAY BE SEPARATED FROM OUTLET STUB AT MOLDED-IN CUT LINE TO ACCOMMODATE A 12 INCH OUTLET PIPE. CONNECTION TO DOWNSTREAM PIPING TO BE MADE USING A FLEXIBLE COUPLING OR ECCENTRIC REDUCER, AS REQUIRED. COUPLING BY FERN CO OR EQUAL AND PROVIDED BY CONTRACTOR. 7) PROVIDE MINIMUM CLEARANCE FOR MAINTENANCE ACCESS. IF A SHALLOWER SYSTEM IS REQUIRED, CONTACT CONTECH STORM WATER SOLUTIONS FOR OTHER OPTIONS. 8) ANTI-FLOTATION BALLAST TO BE SPECIFIED BY ENGINEER AND PROVIDED BY CONTRACTOR, IF REQUIRED. BALLAST TO BE SET AROUND THE PERIMETER OF THE STRUCTURE. 9) ALL STORMFILTERS REQUIRE REGULAR MAINTENANCE. REFER TO OPERATION AND MAINTENANCE GUIDELINES FOR MORE INFORMATION. 30"O FRAME AND COVER (STD) ~. - ,~..: .a ~., `4, .~: ~ gyp.. •/•• MANHOLE STORMFILTER -TOP VIEW 1 2 OUTLET SAND COLLAR RISER 12"O OUTLET STUB as MOLDED-IN CUT LINE -~ ~ 8"PJ OUTLET STUB PRECAST MANHOLE STORMFILTER DATA STRUCTURE ID XXX WATER QUALITY >=LOW RATE (cfs) X.XX PEAK FLOW RATE (< I cfs) X.XX RETURN PERIOD OF PEAK FLOW ( rs) XXX # 01= CARTRIDGES REQUIRED XX CARTRIDGE FLOW RATE (I 5 or 7.5 m) XX MEDIA TYPE {CSF, PERLITE, ZPG) XXXXX RIM ELEVATION XXX.XX' PIPE DATA: I.E. ORIENTATION MATERIAL DIAMETER INLET PIPE # I XXX.XX' XX° XXX XX" INLET PIPE #2 XXX.XX' XX° XXX XX" OUTLET STUB XXX.XX' 0° XXX 8" / 12" ECCENTRIC REDUCER YES\NO SIZE (BY CONTRACTOR) XXX XX" x XX" ANTI-FLOTATION BALLAST WIDTH HEIGHT XX" XX" NOTES/SPECIAL REQUIREMENTS: PIPE ORIENTATION KEY: 90° I 180° --0° I 270° s , ~ OUTLET PIPE (BY CONTRACTOR) . ° COUPLING (BY CONTRACTOR) (SEE NOTE 6) BALLAST GROUT (SEE NOTE 8) (BY CONTRACTOR) MANHOLE STORMFILTER -OUTLET DETAIL ©2006 CONTECH Stormwater Solutions THE STORMWATER MANAGEMENT StormFilter® U.S. PATENT No. 5,322,629, No. 5,707,527, No. 6,027,639 No. 6,649,048, No. 5,624,576, AND OTHER U.S. AND FOREIGN PATENTS PENDING A~~~~ITCALI® PRECAST 48" MANHOLE STORMFILTER DRAWING ~~/~~~ ~ r~.r~ STORMWATER TOP AND SECTION VIEWS, NOTES AND DATA 2 SOLUTIONS~~ STANDARD DETAIL 2n contechstormwater.com DATE:09Y16/05 SCALE: NONE FILE NAME: MHSF3-48PC-DTL DRAWN: MJW CHECKED:ARG Attachment 2 W H Q H `W ,L V/ O U J Q H d W U Z O U N C ~L ,^~ V/ L w O A C O .N .; ,~ V/ N C f3 t U = O O O O O O O O O O O O O O O O O O O O H O O O O O O O O O O O O O O O O O O O O (n O O V 0 0 0 L(7 0 0 0 0 0 0 0 0 0 0 O O O O V N N V O O I~ O H O 00 CO O ~ ~ O O ~ O Ln (~ 00 V EA EA CO V EA ('') ~ O EA ('') O EA EA N O CO N 00 EA EA EA ('~ EA EA ~ EA N EA ~ O ('~ M D ~ ~ ~ ~ ~ ~ ~ W ~3 b9 H Q ~ _ H W 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 W o 0 0 0 0 0 0 0 0 0 0 0 0 0 ~ o 0 0 M U O O O N O O L(7 0 0 0 0 0 0 0 ('') O O O O N EA O ~ EA N O O O O O O EA O O ~ O O EA O EA EA ~ 0 0 0 ~ L(7 O O W V N O ~ ~ V CO ~ ('') O O ~ 00 V ('~ EA EA EA EA N O ~ ~ ~ ~ ~ Z ~» ~ T U ~ y ~ ~ ° o O ° ° ° ° O ~ ~ a~ ~ 0 U z ~ ~ o N O O N O O L(7 O L(7 O I~ o O N CO O p N O p ~ ~ 7 ~ ~+ ~ ~ N ~ ~ ~ ~ ~ N N S O + H C~ U ~ c~ c~ ~ ~ U ~ ~ ~ z ~ Q Q ~ Q ~ c~ c~ z J J J J Q U (~ (~ H U W W J W (~ J J c Z ~ ~ O ~ ~ ~ ~ ~ ~ U ~ ~ ~ W 0 ~ ~ ~ ~ ~ ~ ~ _ .~ U O W ~ _ O ~ ~ ~ V ~ N ~ ~ ~ U ~ ~ a~ N ~ a~ . ~ ~ m ~ ~~ ca 0 a~ c o c c m c~i ~ a~ 0 ~ ~ ~ °~ ~ U ~ m ~~n c 0 ~ i ~ ~ ~ Q ~ ~ ~ ~ n ~ a~ ~ i ~ ~ ~ ~ o c ~ _ ±' otS c p o CO a~ ~ 0 ~ ~p - ~ O c W ~ c ~ N N ~ ~ ~ j .N ~ ~ D ? ~ ~ ~ N ~ .~ Y Y (6 U ~ ,O N ~ ~ ~ ~ ~ ~ ~ ~ ~ (n (n U W (n O (n U ~ H N ~ (~ W W ~ W ~ rn Q H ~ ~ LL Q N (~ ~ ~ O ~ 6~ N ~ aN0 N ~ N W ~ ~ ~ ~ ~ ~ V I~ r I~ ~ ~ 6i X 0 0 ~ N V V 0 0 0 L(7 V ('') L(7 L(7 O O O O O O O O O ~ N CO 00 ('') L(') N N ('') ('') I~ O O ~ N ('~ V ~ CO ~ a0 O ~ ~ ~ ~ ~ ~ ~ ~ z W H Q ~_ H `W ,L V/ O U J Q H d W U Z O U N C ~L ,^~ V/ L t~ w O U C O +. :a Q C O U N O C L O L 0 Z N U c3 L H O v c c~ O ~_ `o Z O O O O O O O O O O O O O O O O O O O O O O O H O O O O O O O O O O O O O O O O O O O O O O O (n O O V 0 0 0 0 0 0 0 00 0 0 0 0 0 0 L(') O O O O O O O O N L(7 L(7 O O O CO O O CO N O O I~ V 0 0 0 O V M O N ~ EA EA ('~ CO ('~ N CO O ~ ~ ('~ L(7 I~ EF3 EF3 ~ a0 L(') ~ ('~ r N ~ ~ CO EA ~ EA ('~ EA EA ~ ('~ N EA EA N I~ a0 (O D EA EA EA EA EA EA EA EA EA EA N EA ~.,~ W ~3 b9 H Q ~ _ H W 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 W o 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ~ o 0 0 M U O O O N O O L(7 0 0 0 0 0 0 0 0 0 0 ('') O O O O N EA O ~ EA N O O O O O O L(7 O O EA O O ~ O O EA O EA EA ~ O CO 0 0 ~ ~ L(7 O O O ~ O O O ~ ~ ('') V CO ~ ~ ('') V O O ~ N ~ ('') fA fA fA fA fA fA N L(7 N ~ cf? cf3 N Z ~» ~» ~» ~ T U ~ y ~ ~ o °O o O °O °O 0 0 °O ° °O O ~ ~ a~ ~ 0 U z ~ ~ N L(7 L(7 O O O CO O ('') V N N ~ O a0 N ~ O V ~ 7 ~ - f3 ++ ~ ~ N ~ CO CO ~ M (~ ~ (~ ~ O H C~ U ~ c~ c~ w w U ~ ~ ~ z ~ Q Q Q w w Q Q ~ Q c~ z J J J J Q U (~ (~ H U W W W J J W W (~ W J ~ N ~ o Z ~ ~ O ~ ~ ~ ~ W ~ ` ~ o ~ U ~ o ~ ~ w o a~ w ~ a~ a~ ~ a~ ~ _ _ ~ U W ~ a i ~ ~ ~ - ~ o f o o - v - ~ ~ a~i ~ ~ ~ U ~ a~ a~ N c~ ~ a~ . ca ~ m ~ ~~~-, ~ bo c c ~ o ~ o m c m o ~ o o ~ ~ ~ ? 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U U ~ A N ~ ( ~ ~ ~ LL ~ 0 ~ x ~ ~ C ~ E O ~ _ ~ m O W > C (6 ~ ~ N ~ ~ O N N 'O 'O ~ O D _ ~ N ~ ~ N ~ O O (6 ~ (6 ~ ~_ ~ (n (n ~ ~ ~ N ~ O (n W ~ W ~ rn Q H ~ ~ ~ Q ~ , V ~ N 6~ ~ a0 ~ N O N N N ( ~ N ~ ~ ~ ~ ~ W ~ ~ ~ ~ ( ~ O ~ ~ O ~ V V L(7 L(7 L(7 O O V O O O O N N N ('') ('') N I~ O ~ N ('~ V ~ CO ~ a0 O ~ ~ z ~ o 0 0 0 0 0 0 cn o ~ o 0 0 0 0 O L(~ 0 0 CO N O O U ~» ~ v ~» co ~ ao ~ ~ ~ ~ ~ 0 W Q W 0 0 0 0 0 W o ~ o o ~ U o ri o 0 M ° ~ ° ° ~ o o o ~ Sri o co ~ ~ ~ ~ Z ~ T U ~ y ~_ ° ° ~ a~ U ~ ~ O N ~ ~ °~ O ~ ~ O H C~ U W H ~ z ~ ~ J ~ (n Q W ~ J Q ~_ y +~+ N H ~ ~ C W ~/Q~ a O ` r A L O ~ +' 0 U ~ ~ ~ J ~ f3 ~ Q J ~ ~ O D 0 N d ~ ~ ~ ~' ~ L O W U z ~ C z Z ~ O U ~ o ~ _ U ~ ~ ~ W D ~ ~ U W ~ ~ ~ ~ a~ - ~ c~ ~ ~ m ~ U ~ (6 ~ N U D c o ~ a c .~ ~ .~ N_ ~ N ~ . ~ (n (n W ~ W O ~ ~ Q N ~ N W ~ ~ O O ~ O O O O I~ O O r ~ ~ ~ z ~ N ('') V a D U W H y ~ y ~ ~ _ 7 ~ .~ ~ U ~ W L ^ ~ Q I..L L r ~ L ~ L O ~ +~ 0 U ~_ ~U~ J ~ f3 N Q ~ J - ~ ~ ~ ~ ~ O W ~ ~ y U z U H O O ~ U H O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O (n 0 0 0 0 0 0 0 0 0 0 L(7 O L(7 L(7 O O O O ('') N CO O O 00 00 00 O O O 00 O O V O M (~ CO EA EA CO O ~ EA ~ O O ~ EA ~ CO CO ('') O ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ 0 ~ ~ ER W H Q ~ _ H W 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 W o 0 0 0 0 0 0 0 0 0 0 0 ~ o M U O O N O O O O O O O O O ('') O ~ O O N EA O O ~ 0 CO 0 0 0 0 0 L(7 O L(7 O O EA O L(7 W ('') EA O EA ('') V CO ~ ~ ~ ~ ('') V O ~ CO ('~ EA EA EA EA EA CO Z ~ ~ ~ ~ T U ~ y ~ ~ 0 o ° O o o o O ~ ~ ~ °~ ~ 0 U Z ~ O 0 p N 0 L(7 N ('') o p ~ ('') N O p ~ 7 ~ ~+ M O ~ M ~ + ~ M O H C~ U ~ c~ ~ ~ U ~ Q Q Q ~ ~ Q Q ~ c~ z J J J Q U W W W J J W W (~ J Z O ~_ U W 0 a~ a~ W ~ ~ ~ v ~ a~i N N N N ('~ N C - X U U O O ~ ~ m U Q i ? 0 U 0 U . 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N O +) U ~ c3 U ~ ~ J ~ fC ?r ~ ~ Q J ~ O 0 ?~ ~ ~ ~ ~=~ ~ y W U U ~ Z O cn z ~ ~ E O U ~ ~ ~ ~ U ~ W ~ D ~ ~ ~ W ~ ~ o ~ cn - ~ ~ U - ~ ~ ~ N ~ D C ~ i ~ O ±' N C (6 ~ ' ~ ~ N N ~ ~ i ~ N ~ . ~ (n (n (n W ~ W O ~ LL Q (+7 N ~ N W ~ ~ ~ O O ~ V 0 0 0 O O I~ O O r r ~ ~ ~ a D U W H Q ~_ H `W ,L V/ O U J Q ^H I..L W U Z O U N C ~L ,^~ V/ L N C w O t~ U f3 N M0 W N c .Q L t~ H 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 O O O O O O (n 0 0 0 0 0 0 0 L(7 L(7 O O O O O CO N ('') O O CO O ('~ ('~ a0 N a0 O U ~ ~ ~ ~ o ~» ~ ~» ~» ~ rn ~ ~ W Q W 0 0 0 0 0 0 0 0 0 0 0 ° W o 0 0 0 0 0 0 0 ~ o M U o o c~i o o o o o ri o ~ °o ~ ~ o ~ oo o o ~» oo ~ co o co ~ ri ao ~ ~ ~ ~ ~ Z ~ ~ ~ ~ T U ~ y ~ ~ 0 o 0 ° 0 o O o O O ~ ~ ~ °~ ~ 0 U z ~ o ~ ~ ~ o ~ o ~ ~ ~ +v C~ U ~ c~ ~ ~ U ~ Q ~ Q ~ c~ z J J J Q U W J W (~ J Z O ~_ U W D ~ W ~ ~ ~ v a i N 'p N N N N C LL (6 ~ ~ ~ O U 0 ~ ~ C ~ c ~ a i a i ~ C ~ ~ ~ = U ~ 0 7 = ~ C ~ ~ O ~ C W C (6 ~ ~ C N 'N N N '~ > ~ _ N N ~ C . p (6 (6 N W N _ ( W ~ (n (n U ~ ~ n ~ W ~ rn p ~ - ~ ° 0 LL Q N (~ ~ ~ ~ aN0 N ~ W i i i i i i i i i 0 ~ V V O O L(7 O O O O O O O ~ N N ('') ('') I~ O ~ N ('~ V ~ CO ~ a0 O ~ z ~ o 0 0 0 0 0 0 cn o ~ o 0 0 0 0 O ('') N O V O ~ ~ (~ ~ cfT N ~ ~ V ~ ~ ~ ~ ~ ~ D ~ ~ ~ W Q W 0 0 0 0 0 W o ~ o o ~ U o ri o 0 M ° ~ ° ° ~ o o o ~ ri o v ~ » ~ Z ~ T U ~ y ~ O ~ 0 ~ U ~ o ~ ~ ~ ~ ~ ~ ~ ~ o H C~ U N ~ ~ W •~ H ~ ~ Z ~ (~ J ~ (~ Q W (~ J Q ~ ~_ fA 7 H ~ ~ ~ W ~~ ~3 '~ ^ I..L 0 r ~ L 0 O ~ +' U ~ ~ 'a J ~ N ' ~ O D \ N ~ fA ~= ~ O W ~ U Z ~ Z ~ ~ ~ O ~ ~ o U ~ ~ U ~ c ~ ~ 0 ~ ~ U W ~ ~ ~ ~ a~ - ~ c~ ~ ~ m ~ U ~ (6 ~ N U D c o ~ a c . ~ . ~ ~ N_ ~ N ~ . ~ (n (n W ~ W O ~ ~ Q N ~ N W ~ ~ O O ~ O O O O I~ O O r ~ ~ ~ z I~INI~I~ a 0 U ~ o 0 0 0 0 0 0 cn o ~ o 0 0 0 0 O ('') N O V O ~ ~ (~ ~ cfT N ~ ~ V ~ ~ ~ ~ ~ ~ D ~ ~ ~ W Q W 0 0 0 0 0 W o ~ o o ~ U o ri o 0 M ° ~ ° ° ~ o o o ~ ri o v ~ » ~ Z ~ T U ~ y ~ o ~ O ~ U ~ o ~ ~ ~ ~ ~ ~ ~ ~ o H C~ U W H ~ z ~ ~ J ~ (n Q W ~ J Q ~ y C O ~ ~ fA C ~ ~ . . W > Q d ` ~/ r A L O ~ t~ U ~ ~ ~ _ J ~ to Q ~ J ~ ~ O p O a~ ~ ~ ~ w ~' ~ o ~ Z U ~ z ~ ~ ~ O U ~ o ~ U _ ~ ~ ~ W D ~ ~ U W ~ - ~ ~ ~ a~ ~ c~ ~ ~ m ~ U ~ (6 ~ N U D c o ~ a c .~ ~ .~ N_ ~ N ~ . ~ (n (n W ~ W O ~ ~ Q N ~ N W ~ ~ O O ~ O O O O I~ O O r ~ ~ ~ z ~ N ('') V a D U consulting ~ engineering ~ construction ~ operations ®CDM is a registered trademark of Camp Dresser & McKee Inc.