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HomeMy WebLinkAbout2023 10 23 Consent 308 - Tuskawilla Crossings Subdivision - Pond 1 Repair and RehabilitationCONSENT AGENDA ITEM 308 CITY COMMISSION AGENDA | OCTOBER 23, 2023 REGULAR MEETING TITLE Tuskawilla Crossings Subdivision - Pond 1 Repair and Rehabilitation SUMMARY On August 31, 2023 a massive berm failure occurred to Pond 1, located in the Tuskawilla Crossings subdivision. In order to repair and rehabilitate the existing stormwater pond facility Pegasus Engineering and its sub-consultants will thoroughly investigate the cause(s) of the failure and prepare design and permitting documentation in order to restore the existing facility and its amenities. FUNDING SOURCE The funding source is the Third Generation Penny Sales Tax. RECOMMENDATION City staff request approval of the design and permitting services measures required to address failure of a stormwater pond berm located in the Tuskawilla Crossings subdivision. Staff requests the Commission authorize the Interim City Manager and City Attorney to prepare and execute a contract and any related documents required with Pegasus Engineering. Design services led by Pegasus Engineering will also include sub-consultants for survey, geotechnical, structural and ecological services. The total fee for these services is $178,750. 293 “Engineering a Higher Standard” 301 West State Road 434, Suite 309, Winter Springs, FL 32708 · 407-992-9160 · Fax 407-358-515 October 17, 2023 P-229804 Mr. Phillip Hursh, P.E. Interim City Manager City of Winter Springs 1126 East State Road 434 Winter Springs, Florida 32708 phursh@winterspringsfl.org Re: Tuskawilla Crossings Subdivision City of Winter Springs, Florida Subj: Pond 1 Repair and Rehabilitation Dear Phil: In follow-up to our previous discussions, we are pleased to submit the following documents for the above referenced project pursuant to the requirements of the City’s Master Agreement for Continuing Engineering Services – Road and Transportation Facilities, Stormwater Engineering and Flood Control: ·Exhibit "A" (Scope of Work); ·Exhibit “B” (Manhour and Fee Estimate); ·Exhibit "C" (Sub-consultant Proposals); and ·Exhibit "D" (Preliminary Assessment of the Pond 1 Berm Failure). We look forward to completing this important assignment for the City of Winter Springs. If you have any questions regarding the enclosed documents, please contact me at 407-992-9160, extension 309 (office), 407-247-0003 (cell), or by e-mail at david@pegasusengineering.net. Sincerely, PEGASUS ENGINEERING, LLC David W. Hamstra, P.E., CFM Stormwater Department Manager cc: Greg Teague, Pegasus Engineering 294 Mr. Phillip Hursh October 17, 2023 Page 2 Tuskawilla Crossings Subdivision City of Winter Springs, Florida Pond 1 Repair and Rehabilitation Approved for Pegasus Engineering, LLC _______________ _____Principal October 17, 2023 Fursan Munjed, P.E.Officer’s Title Date This proposal is hereby accepted and authorization to proceed is hereby given. (Please return one executed copy of this proposal for our Pegasus Engineering records). _______________ _______________________ Authorized Signature Officer’s Title Date 295 TUSKAWILLA CROSSINGS SUBDIVISION CITY OF WINTER SPRINGS, FLORIDA POND 1 REPAIR AND REHABILITATION Exhibit “A” Scope of Work 296 EXHIBIT "A"–SCOPE OF WORK TUSKAWILLA CROSSINGS SUBDIVISION POND 1 REPAIR AND REHABILITATION A-1 P-229804 1.0 BACKGROUND DISCUSSION Tuskawilla Crossings Subdivision is located south of State Road 434, east of Tuskawilla Road, adjacent to Indian Trails Middle School, within the Howell Creek tributary to Lake Jessup (refer to Figure 1). Figure 1 Vicinity Map The subdivision encompasses 133.3 acres, including a community park (pool, playground, dog park, etc.) and 747 residential lots that were constructed in two (2) separate phases pursuant to SJRWMD Permit 148395-1 that was issued on May 11, 2017. Seminole County’s Cross Seminole Trail bisects the property into unequal north and south parts (refer to Figure 2). ·Tuskawilla Crossings – Phase 1 (379 lots) .................................... Plat Book 83, Pages 75-89 ·Tuskawilla Crossings – Phase 2 (368 lots) .................................. Plat Book 84, Pages 48-55 1 1 A replat of future development Tracts FD-1, FD-2, FD-3, FD-5, and FD-6 of Tuskawilla Crossings Phase 1. City of Winter Springs Municipal Limits Tuskawilla Crossings 297 JOB NO.:MK-03DATE:10 / 2023FIGURE301 WEST STATE ROAD 434, SUITE 309 WINTER SPRINGS, FL 32708 TEL: 407-992-9160 FAX: 407-358-5155 WEB: WWW.PEGASUSENGINEERING.NET POND 1 REPAIR AND REHABILITATION TUSKAWILLA CROSSINGS 2AERIAL LOCATION MAP SCALE: 1" = 400'4000123456728797101110121313101MICHAEL BLAKE BOULEVARD2WOODED VINE DRIVE3GENTLE BREEZE LANE4WISE OWL WAY5SILVER MOON LANE6SWIFT CREEK WAY7DANCING WATER DRIVE8RUSHING RAPIDS WAY9CLEVER FOX LANE10EAGLE WIND TERRACE11SINGING TREE LANE12TRAILHEAD POINT13GRACEFUL DOE LOOPSTREETS WITHIN TUSKAWILLA CROSSINGS PARKAVERYSAVOYTHECROSSINGSEMINOLETOWNHOMESC R O S S S EM I N O L E T R A I LE STATE ROAD 434PO N D 1 WETLANDPOND POND POND FORESTOAKMIDDLE SCHOOLINDIAN TRAILSTUSKAWILLA ROAD FAILUREBERMTUSKAWILLACROSSINGSCROSS SEMINOLE TRAILPOND UNIT 9TUSKAWILLACROSSINGSTUSKAWILLACASA PARKVILLASAERIAL IMAGE DATED 2021FDOT OFFICE OF SURVEYING AND MAPPING(COMMERICAL)TRACT FD-4PARKCOMMERICAL298 EXHIBIT "A"–SCOPE OF WORK TUSKAWILLA CROSSINGS SUBDIVISION POND 1 REPAIR AND REHABILITATION A-3 P-229804 Site work began in late 2017 and construction of the residential lots was complete in late 2021. Construction of the commercial development platted on Tract FD-4 located immediately south of Michael Blake Boulevard has not started as of October 2023 and an application for Environmental Resource Permit (ERP) was not located on SJRWMD e-Permitting. The permitted stormwater management system includes a total of five (5) wet detention stormwater ponds that discharge to wetlands and conservation areas identified on the subdivision plat as Tracts A, B-1, B-2, C, and D (refer to Figure 2). The operation and maintenance phase of the stormwater management system began on December 17, 2019 when District staff issued SJRWMD Permit 148395-3. The scope of work for this proposal pertains specifically to Pond 1, which is located south of State Road 434, and north and east of the Cross Seminole Trail. Pond 1 comprises approximately 3.79 acres at the top of bank elevation 26-ft, NAVD and provides stormwater management for a contributing drainage area of 47.72 acres.2 The water quality and pollution abatement volume provided within Pond 1 is recovered by a 6- inch diameter circular orifice that is connected to a proprietary Nutrient Removal Filtration System (NRFS) that was installed to address the District’s nutrient removal criteria for discharges to Lake Jessup. Overflow discharge from Pond 1 is conveyed to the adjacent wetland and conservation area (Tract B-1) by a broad crested concrete weir. Figure 3 Aerial (Drone) Photograph of the Pond 1 Drawdown and Overflow Structures 2 Stormwater Management System Report for Tuskawilla Crossings prepared by B&S Engineering Consultants (aka, Appian Engineering) and dated February 15, 2017. Broad Crested Concrete Weir Pond 1 NRFS Structure Fiberglass Skimmer Tract B-1 Drawdown Orifice 299 EXHIBIT "A"–SCOPE OF WORK TUSKAWILLA CROSSINGS SUBDIVISION POND 1 REPAIR AND REHABILITATION A-4 P-229804 Sometime in late August or early September 2023, a berm failure occurred on the north side of Pond 1 that resulted in a nearly vertical breach that rapidly drained the pond with significant soil loss and sediment deposition within the downstream wetland and conservation area (Tract B-1). Figure 4 Photograph of the Pond 1 Berm Failure Looking Northeast Towards the Wetland and Conservation Area (Tract B-1) Approximate Width = 30’ Pond 1 Tract B-1 300 EXHIBIT "A"–SCOPE OF WORK TUSKAWILLA CROSSINGS SUBDIVISION POND 1 REPAIR AND REHABILITATION A-5 P-229804 In addition to the berm failure, the following deficiencies will also need to be addressed as part of repairing and rehabilitating Pond 1, and it is very likely that additional deficiencies will also be discovered after engineering design commences. ·Side slope erosion around the entire pond perimeter. ·Localized erosion of the pond berm and side slope caused by a rear yard drainage system located at 1533 Graceful Doe Loop. ·Elevated pond control water level caused by the drawdown orifice and the NRFS structure. ·Damaged fiberglass skimmer for the broad crested concrete weir. ·Erosion potential between the broad crested concrete weir and the downstream wetland and conservation area (Tract B-1). ·Erosion and scour at the outlet ends of the storm pipes that discharge into Pond 1. ·Exposed storm pipe and joint along the Pond 5 outfall system just after the 90 degree turn along the south side of Pond 1. It should be noted that possible causes of this deficiency could include: a leaking pipe joint; erosion, soil loss and limited pipe cover; and groundwater seepage related “gouging” that is occurring between the Cross Seminole Trail and Pond 1. ·Horizontal sock drains that were left over from the original pond dewatering that have been exposed and ruptured by the rapid loss of water in Pond 1. ·Repair and reconstruction of the berm breach. The reader is also referred to a preliminary assessment of the Pond 1 berm failure prepared by Pegasus Engineering (refer to Exhibit “D”). 301 EXHIBIT "A"–SCOPE OF WORK TUSKAWILLA CROSSINGS SUBDIVISION POND 1 REPAIR AND REHABILITATION A-6 P-229804 2.0 PROFESSIONAL ENGINEERING SERVICES Pegasus Engineering, LLC (Consultant), shall provide the engineering services as itemized on the Manhour and Fee Estimate provided as Exhibit “B”. Referring to the information provided within Exhibit “C”, this proposal also includes services from the following sub-consultants. Survey Sub-consultant .................................. Southeastern Surveying & Mapping Corp. (SSMC) The topographic survey limits were defined to encompass all of the Pond 1 deficiencies that were previously discussed, and will also include the area downstream of the berm breach where eroded soils have been deposited in the downstream wetland and conservation area (Tract B-1). Refer to the “Basis of Proposal / Assumptions” section of this proposal for additional discussion regarding sediment deposition within the downstream wetland. Geotechnical Sub-consultant ............................................................ Devo Engineering (DEVO) The geotechnical investigation will assess soil conditions at the berm failure, identify the primary cause of the berm failure and provide specific recommendations for repairing and reconstructing the Pond 1 berm. Pegasus Engineering will use the figures and recommendations presented within the geotechnical report to prepare construction plans for the proposed berm repair and reconstruction. Because repairing and re-constructing the berm failure is a critical component that involves atypical work, the geotechnical sub-consultant has also included some limited post-design service related to construction oversight. Structural Sub-consultant ............................................Florida Bridge and Transportation (FBT) Because the geotechnical sub-consultant anticipates that repairing and re-constructing the Pond 1 berm using compacted fill will not be sufficient to adequately prevent the possibility of a future failure, a sheet pile wall will be designed by the structural sub-consultant based on recommendations presented within the geotechnical report. The structural sub-consultant has also included some limited post-design services for reviewing and approving submittals related to the sheet pile wall. 302 EXHIBIT "A"–SCOPE OF WORK TUSKAWILLA CROSSINGS SUBDIVISION POND 1 REPAIR AND REHABILITATION A-7 P-229804 3.0 GENERAL The Consultant will adhere to the following procedures throughout the course of the contract. 1.Construction plans will be prepared to scale on 24” x 36” sheet size. A single set of construction plans will be prepared that is suitable for public bid and ready to award for construction. All design parameters, surveys, and construction plans will be prepared and submitted in English standard units. 2.Construction cost estimates shall show quantity breakdowns of all items following the Florida Department of Transportation (FDOT) numbering system. 3.Digital copies of all construction plans and work products shall be provided at the conclusion of the contract. 4.0 BASIS OF PROPOSAL / ASSUMPTIONS The following conditions and assumptions are noted as qualifications to this proposal. 1.This proposal does not include the following professional services. In the event that any of these services are required in the future, it is assumed that an amendment will be processed to encompass those additional services. ü Stormwater modeling for proposed conditions. ü Permitting related to Section 404 of the Clean Water Act, including any applications submitted to the U.S. Army Corps of Engineers (USACE) for “retained waters” or the Department of Environmental Protection (DEP) for “assumed waters”. ü Permitting with Seminole County related to the Cross Seminole Trail. ü Permitting with the Florida Department of Environmental Protection (FDEP) to relocate existing water and/or sewer lines within the limits of construction. ü Modification or relocation of existing utility systems. ü Maintenance of Traffic (MOT) operations and Traffic Control Plans (TCP). ü Ecological assessments and wetland mitigation. 303 EXHIBIT "A"–SCOPE OF WORK TUSKAWILLA CROSSINGS SUBDIVISION POND 1 REPAIR AND REHABILITATION A-8 P-229804 ü Restoration, tree replacement and/or landscape plans. ü Legal sketches and descriptions for easement acquisition or vacating conservation easements. ü Construction Engineering and Inspection (CEI) services. 2.Environmental restoration to ameliorate the adverse effects of sediments that were transported and deposited within the downstream wetland and platted conservation area (Tract B-1) is not recommended. Accurately defining the areal extent of sediment deposition and estimating the volume of sediment removal are both very difficult tasks, and removing the sediments can often result in causing more environmental damage than environmental benefit. Based on our experience with previous projects, environmental restoration through natural recruitment and regeneration from existing seed source is recommended. However, this will need to be discussed with District staff to determine if the sediment discharge will be considered an unauthorized filling of a wetland or the result of a natural disaster. 3.Because the proposed construction activities are anticipated to result in more than 1-acre of disturbed land, a National Pollutant Discharge Elimination System (NPDES) construction permit application from the Environmental Protection Agency (EPA) will be required. However, and although a Storm Water Pollution Prevention Plan (SWPPP), Notice of Intent (NOI) and Notice of Termination (NOT) are applicable to this project, task assignments related to NPDES permitting are not included in the scope of work for this proposal. 4.Permit application fees are not included and will be provided by others. 5.The bid advertisement will disseminate electronic files (in PDF format) instead of hard copies. 304 TUSKAWILLA CROSSINGS SUBDIVISION CITY OF WINTER SPRINGS, FLORIDA POND 1 REPAIR AND REHABILITATION Exhibit “B” Manhour and Fee Estimate 305 EXHIBIT "B" - Manhour and Fee Estimate Tuskawilla Crossings Subdivision Pond 1 Repair and Rehabilitation Task Description (See Note 1 Below)Department Project Sr. Project CADD Admin. (Effective Date : October 17, 2023)Manager Manager Engineer Technician Assistant Hourly Rate $177.91 $177.91 $161.46 $95.68 $74.75 A Project Administration 0.0 $0.00 A1 => Prepare and issue the sub-consultant NTP letters and contract agreements 2.0 2.0 4.0 $505.32 A2 => Coordinate with the sub-consultants 4.0 4.0 $711.64 A3 => Conduct a field review and take project photographs 4.0 4.0 8.0 $1,357.48 A4 => Perform sufficiency reviews of the preliminary sub-consultant deliverables 8.0 8.0 $1,423.28 A5 => Coordinate with County staff regarding the Cross Seminole Trail 2.0 2.0 $355.82 A6 => Coordinate with City staff regarding construction access, staging and stockpiling 2.0 2.0 $355.82 A7 => Two (2) meetings with City staff or other interested parties 4.0 4.0 $711.64 A8 => Conduct one (1) neighborhood meeting or public workshop 6.0 12.0 18.0 $3,202.38 A9 => Conduct one (1) presentation to the City Commission 6.0 12.0 18.0 $3,202.38 A10 => QA/QC the final project deliverables 8.0 8.0 $1,291.68 A11 => Monthly status reports via invoices 8.0 8.0 16.0 $2,021.28 B Construction Plans 0.0 $0.00 B1 => Cover Sheet 4.0 4.0 $711.64 B2 => General Notes 2.0 2.0 $355.82 B3 => Aerial Location and Drainage Map 12.0 12.0 $2,134.92 B4 => Topographic Survey (by others)4.0 4.0 $711.64 B5 => Existing Conditions Plan with Deficiency Photographs 8.0 8.0 $1,423.28 B6 => Overall Plan and Construction Access, Staging and Stockpiling 2.0 16.0 18.0 $3,202.38 B7 => Pond Repair and Rehabilitation Site Plan 2.0 36.0 38.0 $6,760.58 B8 => Berm Repair and Rehabilitation Plan 2.0 16.0 18.0 $3,202.38 B9 => Overflow Weir Repair and Rehabilitation Plan 12.0 12.0 $2,134.92 B10 => Pond Cross Sections 12.0 12.0 $2,134.92 B11 => Sheet Pile Structural Design (by others)2.0 2.0 $355.82 B12 => Temporary Erosion Control Plan and Pollution Control Details 8.0 8.0 $1,423.28 B13 => Drainage Structure Details 12.0 12.0 $2,134.92 B14 => Miscellaneous Details 8.0 8.0 $1,423.28 B15 => Prepare 90% plans for review and comment 8.0 8.0 $1,423.28 B16 => Revise the 90% plans to address the review comments 32.0 32.0 $5,693.12 B17 => Prepare 100% plans for review and comment 6.0 6.0 $1,067.46 B18 => Revise the 100% plans to address the review comments 16.0 16.0 $2,846.56 Task Hours Task Fees Page 1 P-229804 306 EXHIBIT "B" - Manhour and Fee Estimate Tuskawilla Crossings Subdivision Pond 1 Repair and Rehabilitation Task Description (See Note 1 Below)Department Project Sr. Project CADD Admin. (Effective Date : October 17, 2023)Manager Manager Engineer Technician Assistant Hourly Rate $177.91 $177.91 $161.46 $95.68 $74.75 Task Hours Task Fees C SJRWMD Permitting 0.0 $0.00 C1 => Conduct a SJRWMD pre-application meeting and prepare minutes 2.0 4.0 6.0 $1,067.46 C2 => Prepare an engineering report narrative to accompany the SJRWMD ERP application 24.0 4.0 28.0 $4,652.56 C3 => Evaluate outfall structure modifications related to pond drawdown and recovery 8.0 8.0 $1,291.68 C4 => Evaluate nutrient removal alternatives 2.0 12.0 14.0 $2,490.74 C5 => Prepare and submit a SJRWMD ERP application (Sections A, C and E)16.0 2.0 18.0 $3,037.92 C6 => Prepare responses to one (1) SJRWMD request for additional information (RAI)2.0 16.0 2.0 2.0 22.0 $3,716.66 D Bidding 0.0 $0.00 D1 => Prepare the 90% Engineer's Estimate of the Probable Construction Cost 8.0 8.0 $1,423.28 D2 => Prepare the 100% Engineer's Estimate of the Probable Construction Cost 4.0 4.0 $711.64 D3 => Prepare the final Engineer's Estimate of the Probable Construction Cost 4.0 4.0 $711.64 D4 => Prepare the final construction plans 4.0 4.0 $711.64 D5 => Prepare a bid schedule 2.0 2.0 $355.82 D6 => Prepare the supplemental specifications and special provisions 24.0 24.0 $4,269.84 E Post-design Services 0.0 $0.00 E1 => Prepare for and attend the pre-bid meeting 2.0 2.0 $355.82 E2 => Prepare technical responses for up to five (5) RFIs received from potential bidders 2.0 12.0 14.0 $2,490.74 E3 => Prepare a bid tabulation, evaluation and recommendation 2.0 12.0 14.0 $2,490.74 E4 => Prepare for and attend the pre-construction meeting 2.0 2.0 $355.82 E5 => Review and process shop drawings 24.0 24.0 $4,269.84 E6 => Review and process shop drawing resubmittals 6.0 6.0 $1,067.46 E7 => Address the Contractor's RFIs during construction 2.0 16.0 18.0 $3,202.38 E8 => Prepare for and attend four (4) on-site progress meetings during construction 12.0 12.0 $2,134.92 E9 => Participate in the substantial completion inspection and prepare a "punch list"6.0 2.0 8.0 $1,423.28 E10 => Participate in the final inspection 4.0 4.0 $711.64 E11 => Review the Contractor's as-built drawings and issue sufficiency comments 8.0 8.0 $1,423.28 E12 => SJRWMD As-built Certification and Request for Conversion to Operation Phase 2.0 8.0 10.0 $1,779.10 E13 => Prepare an Engineer's Certification of Completion 4.0 4.0 $711.64 Page 2 P-229804 307 EXHIBIT "B" - Manhour and Fee Estimate Tuskawilla Crossings Subdivision Pond 1 Repair and Rehabilitation Task Description (See Note 1 Below)Department Project Sr. Project CADD Admin. (Effective Date : October 17, 2023)Manager Manager Engineer Technician Assistant Hourly Rate $177.91 $177.91 $161.46 $95.68 $74.75 Task Hours Task Fees TOTAL LABOR HOURS 76.0 464.0 22.0 8.0 10.0 580.0 - - TOTAL LABOR COSTS $13,521.16 $82,550.24 $3,552.12 $765.44 $747.50 - -$101,136.46 PERCENT BREAKDOWN (HOURS)13.1%80.0%3.8%1.4%1.7%100.0%- - NOTES:1. Pegasus Labor Fees = 2. Other Direct Costs = 1. Refer to the proposal scope of work for additional discussions and qualifications.3. Survey Sub-consultant - SSMC = 4. Getoechnical Sub-consultant - DEVO = 5. Ecological Sub-consultant - N/A = 6. Structural Sub-consultant - FBT = > Structural Engineering Design > Structural Post-Design Services TOTAL FEES = $32,885.00 - - - - $178,750.00 $101,136.46 $200.45 $29,430.00 $10,335.36 $4,762.73 Page 3 P-229804 308 TUSKAWILLA CROSSINGS SUBDIVISION CITY OF WINTER SPRINGS, FLORIDA POND 1 REPAIR AND REHABILITATION Exhibit “C” Sub-consultant Proposals 309 Survey Sub-consultant (SSMC) 310 100 % Employee-Owned | www.southeasternsurveying.com Orlando, Florida | Jacksonville, Florida | Chipley, Florida Tampa, Florida | Kissimmee, Florida | Marianna, Florida | Tavares, Florida | Dothan, Alabama October 11, 2023 VIA EMAIL: david@pegasusengineering.net CC: Greg@pegasusengineering.net Mr. David W. Hamstra, P.E./ CFM| Stormwater Department Manager Pegasus Engineering, LLC 301 West State Road 434, Suite 309 Winter Springs, Florida 32708 Cell: 407-247-0003 RE: City of Winter Springs - Tuskawilla Crossings Pond 1 Repair and Rehabilitation Near: State Road 434 and Cross Seminole Trail, Winter Springs, FL 32708 PID: 06-21-31-5VK-0F00-0000 Tract F Tuskawilla Crossings Phase I, Plat Book 83, Pages 75-89 Section 38, Township 21 South, Range 31 East, Seminole County, Florida Dear Mr. Hamstra, We are pleased to submit our proposal for Surveying Services on the above-referenced project. SCOPE OF WORK: Provide a Topographic Survey to meet the Standards of Practice as prescribed by the Florida Board of Professional Land Surveyors in Chapter 5J-17 FAC, Section 472.027 of the Florida Statutes. The survey will include the following: 1. Locate all improvements and utilities, as evidenced by above-ground features or if designated and marked by the Utility Owners, their designated representative, or a contracted service at the original time of field visit. 2. Obtain spot elevations on natural ground and existing improvements suitable for interpolation of one-foot contours to be shown on the final drawing. Cross sections will be performed every 100 feet and tighter in areas that need more detail to produce accurate contours. 3. Establish a minimum of two (2) site benchmarks. 4. Topographic coverage will be limited to the area as shown hatched and outlined in red on the attached Exhibit “B”. 5. Locate rip-rap and extend Topographic coverage 10 feet beyond rip-rap, locate and detail existing yard drainage system and locate and extend Topographic coverage 10 feet beyond sediment deposition; all shown on “Exhibit B”. 6. Locate soil borings performed by a Geotechnical Subconsultant. 7. Locate and detail all existing stormwater and sewer structures, including 1 off scope. 8. Locate trees 8 inches and larger in diameter at breast height (DBH) in the area of the sediment deposition and in the overflow weir area. DELIVERABLE The final product will be three (3) certified prints and an electronic file for your use. The survey drawing will be prepared at a scale of 1” = 20’ on a 24” x 36” sheet size. DELIVERY All documents will be sent to the client or the client’s representative(s) via USPS. If overnight shipping is requested or required by the client or the client’s representative(s), then said charges would appear as a separate item on our invoice unless we are provided with the client’s overnight carrier account number for shipping. 311 Mr. David W. Hamstra, P.E./ CFM| Stormwater Department Manager City of Winter Springs - Tuskawilla Crossings Pond 1 Repair and Rehabilitation October 11, 2023 2 \\navision\admin\Data\Admin Documents\P\Pegasus Engineering, LLC (PEL)\City of Winter Springs (CWS)\RFQ 01-21 TP (W109657)\2_ Proposal Letters\Tuskawilla Crossings\Tuskawilla Crossings Pond 1 Repair & Rehabilitation.docx Utility owners do not designate and mark their utilities as a result of contacting Sunshine 811 during the design phase. Therefore, Southeastern Surveying and Mapping Corporation (SSMC) will request a Design Ticket from Sunshine 811 and provide the utility contact information received from the Design Ticket. ADDITIONAL SERVICES Any service not explicitly provided for in the above scope will be billed as additional services and will be performed at our then current hourly rates as provided for in Exhibit A. INFORMATION PROVIDED BY CLIENT SSMC shall be entitled to rely on the completeness and accuracy of all information provided by the Client or the Client’s consultants or representatives. PROJECT TIMELINE We anticipate the completion of the above-described work within thirty-five (35) business days after receipt of a written notice to proceed. EXPENSES AND FEES Our fee for the above-referenced work will be as follows: Topographic Survey: $29,430.00 PAYMENT TERMS Payment is expected within thirty (30) days from the date of the invoice. PAYMENT OPTIONS SSMC is committed to ensuring our clients have access to various payment options. These options include cash, paper checks, ACH transfers, wire transfers, and credit cards. Credit card payments are subject to a vendor administrative fee of 3.5% of the invoice total. We look forward to the opportunity to work with you on this project. Sincerely, Jesse Hodapp, P.S.M. Survey Project Manager JRH.dcw 312 Mr. David W. Hamstra, P.E./ CFM| Stormwater Department Manager City of Winter Springs - Tuskawilla Crossings Pond 1 Repair and Rehabilitation October 11, 2023 3 \\navision\admin\Data\Admin Documents\P\Pegasus Engineering, LLC (PEL)\City of Winter Springs (CWS)\RFQ 01-21 TP (W109657)\2_ Proposal Letters\Tuskawilla Crossings\Tuskawilla Crossings Pond 1 Repair & Rehabilitation.docx If the above scope, period of service, and method of compensation meets with your approval, please have an authorized person execute below and send via email to contracts@southeasternsurveying.com as an official notice to proceed along with the notice of commencement. Fees and times stated in this agreement are valid for six months from the date of the proposal. CLIENT AUTHORIZATION I declare that I am authorized to sign the binding contractual document. I also declare that I have read, understand, and accept this proposal. Signature Date Printed Name Title (if any) 313 Mr. David W. Hamstra, P.E./ CFM| Stormwater Department Manager City of Winter Springs - Tuskawilla Crossings Pond 1 Repair and Rehabilitation October 11, 2023 4 \\navision\admin\Data\Admin Documents\P\Pegasus Engineering, LLC (PEL)\City of Winter Springs (CWS)\RFQ 01-21 TP (W109657)\2_ Proposal Letters\Tuskawilla Crossings\Tuskawilla Crossings Pond 1 Repair & Rehabilitation.docx EXHIBIT “A” HOURLY RATES Professional Surveyor & Mapper $162.00/per hour Project Manager (Survey) $162.00/per hour Project Manager (SUE) $162.00/per hour Senior Technician (Survey) $122.00/per hour Senior Technician (SUE) $122.00/per hour CAD Technician $108.00/per hour 2 Person Survey Field Crew $163.00/per hour 3 Person Survey Field Crew $214.00/per hour 4 Person Survey Field Crew $265.00/per hour 2 Person SUE Field Crew $198.00/per hour 3 Person SUE Field Crew $276.00/per hour 314 Mr. David W. Hamstra, P.E./ CFM| Stormwater Department Manager Tuskawilla Crossings Pond 1 Repair & Rehabilitation October 11, 2023 5 \\navision\admin\Data\Admin Documents\P\Pegasus Engineering, LLC (PEL)\City of Winter Springs (CWS)\RFQ 01-21 TP (W109657)\2_ Proposal Letters\Tuskawilla Crossings\Tuskawilla Crossings Pond 1 Repair & Rehabilitation.docx EXHIBIT “B” PROJECT LIMITS 315 FEE QUOTATION PROPOSAL Project Name:Date: Contract:Name of Firm: Hrly Rate:$162.00 Hrly Rate:$162.00 Hrly Rate:Hrly Rate:$108.00 Hrly Rate:$163.00 Hrly Rate: Man Hrs Fee Man Hrs Fee Man Hrs Man Hrs Fee Man Hrs Fee Man Hrs 5 810.00$ 5 810.00$ 10 50 5,400.00$ 130 21,190.00$ 29,430.00$ 5 5 10 50 130 Lump Sum Fee Breakdown Project Manager Surveyor & Mapper/PSM Senior Technician CAD Technician 2 Person Field Crew Clerical & Mileage Additional Fees Additional Fees Additional Fees Lump Sum Fee Total CAD Technician 2 Person Field Crew 1,220.00$ 5,400.00$ 21,190.00$ Clerical & Mileage Activity Fee Total 810.00$ Total Hours Senior Technician October 11, 2023City of Winter Springs - Tuskawilla Crossings Pond 1 Repair and Rehabilitation Topographic Survey Southeastern Surveying and Mapping CorporationSSMC Standard Hourly Rates Project ManagerActivity $122.00 Fee 1,220.00$ Surveyor & Mapper/PSM 810.00$ 29,430.00$ \\navision\admin\Data\Admin Documents\P\Pegasus Engineering, LLC (PEL)\City of Winter Springs (CWS)\RFQ 01-21 TP (W109657)\2_ Proposal Letters\Tuskawilla Crossings\Tuskawilla Crossings Pond 1 Repair & Rehabilitation.xlsx 316 Geotechnical Sub-consultant (Devo Engineering) 317 Date: October 9, 2023 Devo’s Project No.: not yet assigned to: PEGASUS ENGINEERING, LLC 301 W. State Rd. 434, Suite 309 Winter Springs, FL 32708 Phone (407-992-9160, Ext. 311; Email: greg@pagasusengineering.net attention: Greg A. Teague, P.E., CFM, Project Manager Ref: PROPOSAL FOR: GEOTECHNICAL INVESTIGATION OF ROOT CAUSE OF SEP 2023 POND 1 BERM BREACH (CONSTRUCTED CIRCA SEP 2018) AND RECOMMENDED CONCEPT RETROFIT TUSKAWILLA CROSSINGS City of Winter Springs, Seminole County, Florida Dear Mr. Teague: Tuscawilla Crossings single family subdivision is located south of State Road 434 and east of Tuscawilla Road in the City of Winter Springs, Seminole County, Fl. The Cross Seminole Trail runs through the relatively new subdivision. Pond 1 of this subdivision is a narrow linear, "inverted L-shaped", wet detention pond (with nutrient removal box) which rims a lower lying wetland. A fill berm with a design top of bank elevation of +26 ft NAVD is on the downhill side of this pond and the height of the fill varies from zero to approximately 7 ft above natural ground. The maintenance berm is 10 ft wide and the pond side slope is 4H:1V to approximate elevation +19 ft NAVD on the inboard slope, and then steepens to 2H:1V to approximate elevation +10 ft NAVD at the bottom. The outboard slope is also 4H:1V or gentler, but the offsite grade drops off into a ditch within the wetland which is at elevation +16 ft NAVD at a distance of about 60 ft from the top of berm at the location of interest. The pond bottom elevation in its deeper lobes (which includes the area of interest) is approximately +10 ft NAVD. With a controlled pond water level 12+ ft above the bottom at +22.6 ft NAVD and a spillway at elevation +24 ft NAVD. This means that there is full water pressure acting on the soil from elevation +10 ft NAVD to generally +22.6 ft NAVD and the base and side of the fill berm below the control elevation are now sustaining this groundwater head elevated above natural ground and water wanting to leak through any permeable contact faces or planes between fill/fill or fill/natural ground. Pond 1 was constructed in calendar year 2018 and was certified complete in April 2019, although Pond 1 is completed by December 2018. In September 2023 (approximately 5 years after construction), the highest portion of the fill berm (approximately 35 ft wide) undermined and suddenly breached over a distance of about 30-35 ft width with sheer sides. Aerial photos show seepage collecting in the wetland at this location in January 2023 Devo Engineering Consulting Geotechnical Engineers Page 1 318 predating the actual berm collapse. More importantly, the berm breach corresponds with a berm excavation at this same location and extent in January 2018 where Pond 1 was isolated to allow drainage into the offsite wetland swale. The failed berm appears to coincide exactly with the berm excavation which appears on the Jan 3, 2018 aerial photo. The water mark line in the pond at the time of the failure is approximately +24.5 ft NAVD which is about 7 ft above the adjacent ditch in the wetland and it appears the berm fill placed within the incision may not have been tied back into the cut surfaces to prevent preferential seepage planes. Horizontal sock drains which were used for the pond dewatering have been exposed and ruptured by the loss of water in the pond (and are now discharging) and the circular depressional fish nests on the sandy slope are also apparent but initial assessment does not indicate that these are root cause factors in the berm breach. The purpose of this report will be to assess the soil profiles on the berm, root cause analysis of the failure, and provide concept recommendations for reinstatement of the berm. Six (6) Standard Penetration Test (SPT) borings are planned and they will be drilled to a depth of 25 ft to provide sufficient data for sheetpile design in the berm which may be 20 ft deep or 25 ft deep but such a cutoff will extend to at least 5 ft below the pond bottom of +10 ft NAVD. Lab testing will be performed on the soil samples to check fines content. The sharp interface of the berm breach indicates a construction discontinuity. Note that our design will be conceptual showing depth and extent of repair and reinstatement but the actual plans and specs will be prepared by Pegasus. Our services will also include limited inspection of the proposed retrofit and consultation with the structural engineer on the final design. Our estimated fee for services is in Table 1 and we can complete this work within 6 weeks of authorization to proceed, although we can provide an interim and conservative repair plan for the berm to discontinue the discharge of water into the wetland system. We appreciate the opportunity to provide this proposal for your review and trust that it covers the work needed. Please feel free to contact us if there are any questions. Claudia Callahan Claudia Callahan, B.Sc. Senior Administrative Assistant Devo Engineering Consulting Geotechnical Engineers Page 2 319 TABLE 1. FEE ITEMIZATION FOR TUSKAWILLA CROSSINGS - BERM FAILURE DESCRIPTION OF WORK ITEM UNIT UNIT COST QUANTITY TOTAL GEOTECHNICAL FIELD SERVICES in Senior Technician - site recon. & coordination of stakeout with surveyor hr $75.00 20.0 $1,500.00 Mobilization/Demobilization of truck rig each $750.00 1.0 $750.00 Site to site movement of drill rig hr $200.00 0.0 $0.00 Senior Engineering Technician to coordinate drilling and record stabilized water table readings and elevation survey hr $75.00 20.0 $1,500.00 Senior Field Inspector hr $75.00 60.0 $4,500.00 Standard Penetration Test boring up to 30 feet ft $18.50 150.0 $2,775.00 Jars for samples case $20.00 4.0 $80.00 Muck survey day $1,000.00 0.0 $0.00 Senior Geotechnical Engineer for field work coordination hr $120.00 6.0 $720.00 GEOTECHNICAL LABORATORY TESTING SERVICES Visual & tactile examination of soil samples each $50.00 4.0 $200.00 Natural moisture content and -200 each $45.00 10.0 $450.00 DATA INTERPRETATION, ANALYSES, AND PREPARATION OF REPORT Principal Engineer hr $130.00 58.0 $7,540.00 Senior Geotechnical Engineer hr $120.00 46.0 $5,520.00 Senior-Level CADD/GIS hr $75.00 58.0 $4,350.00 Mid-level CADD/GIS hr $65.00 40.0 $2,600.00 ADMINISTRATIVE SUPPORT Administrative Assistant hr $50.00 8.0 $400.00 TOTAL FOR ALL TASKS $32,885.00 Devo Engineering Consulting Geotechnical Engineers Page 3 320 AUTHORIZATION To authorize this proposal, please complete the information requested and return by mail or fax. TABLE A.1: AUTHORIZATION OF OFFER This offer is authorized only when signed below otherwise it should be considered a draft. Authorization signature: Devo Seereeram, Ph.D., P.E. Owner To authorize this work, please complete the information below and return a copy of the executed authorization to: Devo Seereeram, Ph.D., P.E. LLC 5500 Alhambra Drive Orlando, FL 32808 Phone: 407-290-2371; devo@devoeng.com TABLE A.2: AUTHORIZATION BY CLIENT Proposal Authorized on this day of 2023 Authorized Signature ........... Print Name & Title ............ Company name .............. Company address............. Company phone # ............ Company fax # .............. Cellular/mobile phone # ........ E-mail address ............... Devo Engineering Consulting Geotechnical Engineers Page 4 321 Structural Sub-consultant (FBT) 322 Florida Bridge and Transportation, Inc. Structural Engineers 633 Dartmouth Street * Orlando, FL 32804 * Phone (407) 513-9709 * Fax (407) 513-9712 October 6, 2023 Mr. Greg Teague, P.E. Pegasus Engineering 301 West SR 434, Suite 309 Winter Springs, FL 32708 RE: Structural Design and Plan Sheet for Sheet Pile Wall Tuskawilla Crossings Pond 1 Berm Failure, City of Winter Springs Proposal for Structural Design Services FBT Project Number 23-74.01 Dear Greg: Florida Bridge and Transportation, Inc. (FBT) is pleased to submit this proposal to PEGASUS for engineering services for the above referenced project. The scope of design services for this work order includes the following: 1) Design and Plan Production: FBT will provide the structural design and plan sheets for the proposed sheet pile walls per the concept shown in the plan provided by Pegasus. It is assumed the sheet pile walls will be cantilever walls (not braced or anchored). FBT will provide design and details for the sheet pile and a concrete coping with railing (if required). The railing will be a standard railing from FDOT Standard Indexes and no custom modifications are included. It is assumed special coating systems (other than coal tar epoxy) and colors for the sheet pile will not be required. Wall control drawings will not be provided (wall geometry will be shown in Pegasus’ plans). The plans and calculations will include one custom design with details for the “short sheets” which will be required to span across the existing storm drain outfall from the retention pond to the creek. The total lump sum for Item #1 and #2 is $10,335.36. 2) Meetings, Specifications and Cost Estimates: FBT will attend one status meeting (if required) with the City staff and Pegasus. The project specifications will consist of the FDOT Standard Specifications for Road and Bridge Construction, and supplemental specifications are not anticipated or included. FBT will provide one estimate of probable construction cost for the structural items. FBT will assist Pegasus develop a bid schedule for the structural items. 3) This proposal includes an allotment of up to 24 hours for post design services such as (but not limited to) site visits during construction and review of RFIs. The maximum limiting amount fee for this task will be $4,762.73 based on an hourly/unit rate basis (Project Manager at $250/hr, SR Engineer at $217/hr, Project Engineer at $143/hr, SR Designer at $138/hour and Engineer Intern at $98/hr). 4) The project deliverables will consist of 100% and signed and sealed “final” plans and structural calculations. We understand the final deliverables may include 24x36 sheets. The reprographic cost for FBT’s portion of the project is included in the fee below. 323 Greg Teague Oct. 6, 2023 Sheet 2 of 2 FBT Tuskawilla Crossing Sheet Pile Proposal 10-6-23 We propose a total lump sum fee of $10,335.36 for all FBT's basic structural engineering services indicated in Item #1 and #2 above, and a maximum limiting amount of $$4,762.73 for the post-design services as described in Item #3 above. The work will be invoiced monthly on a percent complete basis. If the work is stopped by PEGASUS or others for any reason before completion, FBT will be reimbursed for the hours expended up to that point at an average hourly rate of $175 per hour. The scope and fee indicated above does not include the following services: · Braced or anchored wall design and details · Reinforcing steel bar list for the concrete coping · Design and detailing of custom railing (other than standard FDOT railing) · Development of site plans, permitting, utility coordination, etc. · Design or analysis of special coating systems · Post design services exceeding the 24 hour allotment described above · Development of As-Built or Construction Record Drawings · Construction inspection or observation of on-going or completed construction The items indicated above, or any other services not included in the basic scope of design services described above, may be provided for an additional fee. A supplemental agreement must be negotiated prior to the additional work being performed by FBT. Additional services required for this project may be provided based on an addendum to this agreement. Fees for additional services will be addressed on a case by case basis. In order for FBT to perform these services, we will need the following information from others: · Site layout showing overall geometry with top of wall and existing/proposed grades on low side of wall · Survey at the walls including elevations, contours and topo · Geotechnical field work and design recommendations This proposal will become invalid if not executed within 90 days. We are prepared to commence the structural design services upon receipt of written notice to proceed. Very truly yours, Florida Bridge and Transportation, Inc. Mark Niedermann, P.E. President 324 ESTIMATE OF WORK EFFORT AND COST - PRIME CONSULTANT Name of Project: Tuskawilla Crossings Pond 1 Berm Failure Consultant Name: FBT County:Winter Springs Consultant No.: 23-74.01 FPN: N/A Date: 10/6/2023 FAP No.:N/A Estimator: Niedermann SH Salary Average By Cost By Rate Per $98.00 $85.00 $55.95 $38.25 $54.00 $0.00 $0.00 $0.00 $0.00 $0.00 $0.00 $0.00 Activity Activity Task 3. Project Common and Project General Tasks 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 4. Roadway Analysis 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 5. Roadway Plans 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 6a. Drainage Analysis 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 6b. Drainage Plans 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 6c. Selective C&G 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 7. Utilities 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 8. Environmental Permits,and Env. Clearances 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 9. Structures - Misc. Tasks, Dwgs, Non-Tech.18 5 5 3 2 3 0 0 0 0 0 0 0 18 $1,321 $73.41 10. Structures - Bridge Development Report 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 11. Structures - Temporary Bridge 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 12. Structures - Short Span Concrete Bridge 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 13. Structures - Medium Span Concrete Bridge 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 14. Structures - Structural Steel Bridge 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 15. Structures - Segmental Concrete Bridge 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 16. Structures - Movable Span 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 17. Structures - Retaining Walls 40 8 8 10 8 6 0 0 0 0 0 0 0 40 $2,654 $66.34 18. Structures - Miscellaneous 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 19. Signing & Pavement Marking Analysis 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 20. Signing & Pavement Marking Plans 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 21. Signalization Analysis 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 22. Signalization Plans 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 23. Lighting Analysis 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 24. Lighting Plans 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 25. Landscape Analysis 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 26. Landscape Plans 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 27. Survey (Field & Office Support)0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 28. Photogrammetry 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 29. Mapping 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 30. Terrestrial Mobile LiDAR 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 31. Architecture Development 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 32. Noise Barriers Impact Design Assessment 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 33. Intelligent Transportation Systems Analysis 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 34. Intelligent Transportation Systems Plans 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 35. Geotechnical 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! Total Staff Hours 58 13 13 13 10 9 0 0 0 0 0 0 0 58 Total Staff Cost $1,274.00 $1,105.00 $727.35 $382.50 $486.00 $0.00 $0.00 $0.00 $0.00 $0.00 $0.00 $0.00 $3,974.85 $68.53 Check =$3,974.85 Survey Field Days by Subconsultant SALARY RELATED COSTS:$3,974.85 4 - Person Crew:OVERHEAD: 127.67%$5,074.69 OPERATING MARGIN: on raw salary only 27%12% on total $1,073.21 Notes:FCCM (Facilities Capital Cost Money):0.349%$13.87 1. This sheet to be used by Prime Consultant to calculate the Grand Total fee.EXPENSES:5.00%$198.74 2. Manually enter fee from each subconsultant. Unused subconsultant rows may be hidden.Survey (Field - if by Prime)0 4-person crew days @ -$ / day $0.00 SUBTOTAL ESTIMATED FEE:$10,335.36 Subconsultant: Enter Name Sub 1 $0.00 Subconsultant: Sub 2 $0.00 SUBTOTAL ESTIMATED FEE:$10,335.36 Geotechnical Field and Lab Testing $0.00 SUBTOTAL ESTIMATED FEE:$10,335.36 Optional Services $0.00 GRAND TOTAL ESTIMATED FEE:$10,335.36 Senior Engineer Engineer Engineer Intern Senior Designer CADD Staff Classification Total Staff Hours From "SH Summary - Project Manager Staff Classi- fication 12 Staff Classi- fication 9 Staff Classi- fication 10 Staff Classi- fication 11 Staff Classi- fication 6 Staff Classi- fication 7 Staff Classi- fication 8 FBT sheet pile proposal 10-6-23 Fee Sheet - Prime Page 1 of 5 10/6/2023 3:01 PM 325 Project Activity 9: Structures Summary and Miscellaneous Tasks and Drawings Estimator: Niedermann Tuskawilla Crossings Pond 1 Berm Failure N/A NOTE: Signature Block is optional, per District preference No. of Units Hours per Unit No. of Sheets Total General Drawings 9.1 Key Sheet and Index of Drawings Sheet 0 0 0 0 9.2 Project Layout Sheet 0 0 0 0 9.3 General Notes and Bid Item Notes Sheet 0 0 0 0 9.4 Miscellaneous Common Details Sheet 0 0 0 0 9.5 Incorporate Report of Core Borings Sheet 0 0 0 0 9.6 Standard Plans- Bridges LS 0 0 0 9.7 Existing Bridge Plans LS 0 0 0 Bridges 0 Walls 0 Box Culverts 0 9.9 Cost Estimate LS 1 2 2 9.10'Technical Special Provisions and Modified Special Provisions LS 0 0 0 0 2 Task No.Task Total Task 10 Task 11 Task 12 Task 13 Task 14 Task 15 Task 16 Task 17 Task 18 10-16 Bridge 1 0 0 0 0 0 0 0 0 10-16 Bridge 10 0 17 Retaining Walls 40 40 18 Miscellaneous Structures 0 0 Consultant Name FL Bridge Representing Print Name FDOT District Signature / Date Task No.Task Structures - Summary and Miscellaneous Tasks and Drawings Units 9.8 Structures Quantites for EQ Report Design and Production Staffhours Comments 0 Calculated Hours 0 FBT sheet pile proposal 10-6-23 9. Structures Summary Page 2 of 5 10/6/2023 326 Project Activity 9: Structures Summary and Miscellaneous Tasks and Drawings 40 0 0 0 0 0 0 0 40 0 Task No.Task Units No. of Units Hours per Unit Total 9.11 Field Reviews LS 1 4 4 9.12 Technical Meetings LS 1 4 4 9.13 Quality Assurance/Quality Control LS %5%2 9.14 Independent Peer Review LS 1 0 0 9.15 Supervision LS %5%2 12 9.16 Coordination LS 1 4 4 18 Units No of Units Hours/ Unit Total Hours PM Attendance at Meeting Required? Number EA 0 0 0 0 EA 0 0 0 0 EA 0 0 0 0 EA 0 0 0 0 EA 1 4 4 0 EA 0 0 0 0 EA 0 0 0 0 4 0 EA 0 0 0 - - EA 0 0 0 - - 4 0 Carries to 9.12 Carries to Tab 3 Local Governments (cities, counties) Utility Companies Other Meetings Technical Meetings BDR Coordination/Review 90/100% Comment Review Aesthetics Coordination Regulatory Agency Total Meetings Total Project Manager Meetings (carries to Tab 3) PM attendance at Phase Review Meetings is manually entered on General Task 3 PM attendance at Progress Meetings is manually entered on General Task 3 Subtotal Technical Meetings Progress Meetings (if required by FDOT) Phase Review Meetings 9. Structures - Summary and Miscellaneous Tasks and Drawings Structures Nontechnical Subtotal Structures Technical Subtotal Meetings are listed below Comments Comments Coordinate with geotech, civil, City, etc. FBT sheet pile proposal 10-6-23 9. Structures Summary Page 3 of 5 10/6/2023 327 Project Activity 17: Retaining Walls Estimator: Niedermann Tuskawilla Crossings Pond 1 Berm Failure N/A NOTE: Signature Block is optional, per District preference Task No.Task Unit No. of Units Hours/ Unit No. of Sheets Total Hours Comments General Requirements 17.1 Key Sheet Sheet 0 0 0 0 17.2 Horizontal Wall Geometry Per Wall 1 2 2 Permanent Proprietary Walls 17.3 Vertical Wall Geometry Per Wall 0 0 0 17.4 Semi-Standard Drawings Sheet 0 0 0 0 17.5 Wall Plan and Elevations (Control Drawings)Sheet 0 0 0 0 17.6 Details Sheet 0 0 0 0 Temporary Proprietary Walls 17.7 Vertical Wall Geometry Per Wall 0 0 0 17.8 Semi-Standard Drawings Sheet 0 0 0 0 17.9 Wall Plan and Elevations (Control Drawings)Sheet 0 0 0 0 17.10 Details Sheet 0 0 0 0 Cast-in-Place Retaining Walls 17.11 Design EA Design 0 0 0 17.12 Vertical Wall Geometry EA Wall 0 0 0 17.13 General Notes Sheet 0 0 0 0 17.14 Wall Plan and Elevations (Control Drawings)Sheet 0 0 0 0 17.15 Sections and Details Sheet 0 0 0 0 17.16 Reinforcing Bar List Sheet 0 0 0 0 Sheet Pile and Other Retaining Walls 17.17 Design EA Design 1 24 24 Representing Print Name Signature / Date FDOT District Consultant Name FL Bridge FBT sheet pile proposal 10-6-23 17. Str-Retaining Walls Page 4 of 5 10/6/2023 328 Project Activity 17: Retaining Walls Task No.Task Unit No. of Units Hours/ Unit No. of Sheets Total Hours Comments 17.18 Vertical Wall Geometry EA Wall 1 2 2 17.19 General Notes, Tables and Misc. Details Sheet 1 4 1 4 17.20 Wall Plan and Elevations Sheet 1 4 1 4 work with Pegasus to get wall geometry and design cases on the same page 17.21 Details Sheet 1 4 1 4 3 4017. Structures - Retaining Walls Total FBT sheet pile proposal 10-6-23 17. Str-Retaining Walls Page 5 of 5 10/6/2023 329 ESTIMATE OF WORK EFFORT AND COST - PRIME CONSULTANT Name of Project: Tuskawilla Crossings Pond 1 Berm Failure Consultant Name: FBT County:Winter Springs Consultant No.: 23-74.01 FPN: N/A Date: 10/6/2023 FAP No.:N/A Estimator: Niedermann SH Salary Average By Cost By Rate Per $98.00 $85.00 $55.95 $38.25 $54.00 $0.00 $0.00 $0.00 $0.00 $0.00 $0.00 $0.00 Activity Activity Task 3. Project Common and Project General Tasks 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 4. Roadway Analysis 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 5. Roadway Plans 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 6a. Drainage Analysis 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 6b. Drainage Plans 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 6c. Selective C&G 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 7. Utilities 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 8. Environmental Permits,and Env. Clearances 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 9. Structures - Misc. Tasks, Dwgs, Non-Tech.8 3 2 1 1 1 0 0 0 0 0 0 0 8 $612 $76.53 10. Structures - Bridge Development Report 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 11. Structures - Temporary Bridge 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 12. Structures - Short Span Concrete Bridge 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 13. Structures - Medium Span Concrete Bridge 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 14. Structures - Structural Steel Bridge 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 15. Structures - Segmental Concrete Bridge 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 16. Structures - Movable Span 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 17. Structures - Retaining Walls 16 6 5 2 2 1 0 0 0 0 0 0 0 16 $1,255 $78.46 18. Structures - Miscellaneous 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 19. Signing & Pavement Marking Analysis 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 20. Signing & Pavement Marking Plans 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 21. Signalization Analysis 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 22. Signalization Plans 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 23. Lighting Analysis 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 24. Lighting Plans 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 25. Landscape Analysis 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 26. Landscape Plans 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 27. Survey (Field & Office Support)0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 28. Photogrammetry 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 29. Mapping 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 30. Terrestrial Mobile LiDAR 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 31. Architecture Development 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 32. Noise Barriers Impact Design Assessment 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 33. Intelligent Transportation Systems Analysis 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 34. Intelligent Transportation Systems Plans 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! 35. Geotechnical 0 0 0 0 0 0 0 0 0 0 0 0 0 0 $0 #DIV/0! Total Staff Hours 24 9 7 3 3 2 0 0 0 0 0 0 0 24 Total Staff Cost $882.00 $595.00 $167.85 $114.75 $108.00 $0.00 $0.00 $0.00 $0.00 $0.00 $0.00 $0.00 $1,867.60 $77.82 Check =$1,867.60 Survey Field Days by Subconsultant SALARY RELATED COSTS:$1,867.60 4 - Person Crew:OVERHEAD: 127.67%$2,384.36 OPERATING MARGIN: on raw salary only 27%12% on total $504.25 Notes:FCCM (Facilities Capital Cost Money):0.349%$6.52 1. This sheet to be used by Prime Consultant to calculate the Grand Total fee.EXPENSES:0.00%$0.00 2. Manually enter fee from each subconsultant. Unused subconsultant rows may be hidden.Survey (Field - if by Prime)0 4-person crew days @ -$ / day $0.00 SUBTOTAL ESTIMATED FEE:$4,762.73 Subconsultant: Enter Name Sub 1 $0.00 Subconsultant: Sub 2 $0.00 SUBTOTAL ESTIMATED FEE:$4,762.73 Geotechnical Field and Lab Testing $0.00 SUBTOTAL ESTIMATED FEE:$4,762.73 Optional Services $0.00 GRAND TOTAL ESTIMATED FEE:$4,762.73 Senior Engineer Engineer Engineer Intern Senior Designer CADD Staff Classification Total Staff Hours From "SH Summary - Project Manager Staff Classi- fication 12 Staff Classi- fication 9 Staff Classi- fication 10 Staff Classi- fication 11 Staff Classi- fication 6 Staff Classi- fication 7 Staff Classi- fication 8 FBT post design proposal 10-6-23 Fee Sheet - Prime Page 1 of 5 10/6/2023 3:00 PM 330 Project Activity 9: Structures Summary and Miscellaneous Tasks and Drawings Estimator: Niedermann Tuskawilla Crossings Pond 1 Berm Failure N/A NOTE: Signature Block is optional, per District preference No. of Units Hours per Unit No. of Sheets Total General Drawings 9.1 Key Sheet and Index of Drawings Sheet 0 0 0 0 9.2 Project Layout Sheet 0 0 0 0 9.3 General Notes and Bid Item Notes Sheet 0 0 0 0 9.4 Miscellaneous Common Details Sheet 0 0 0 0 9.5 Incorporate Report of Core Borings Sheet 0 0 0 0 9.6 Standard Plans- Bridges LS 0 0 0 9.7 Existing Bridge Plans LS 0 0 0 Bridges 0 Walls 0 Box Culverts 0 9.9 Cost Estimate LS 0 0 0 9.10'Technical Special Provisions and Modified Special Provisions LS 0 0 0 0 0 Task No.Task Total Task 10 Task 11 Task 12 Task 13 Task 14 Task 15 Task 16 Task 17 Task 18 10-16 Bridge 1 0 0 0 0 0 0 0 0 10-16 Bridge 10 0 17 Retaining Walls Post Design 16 16 18 Miscellaneous Structures 0 0 Consultant Name FL Bridge Representing Print Name FDOT District Signature / Date Task No.Task Structures - Summary and Miscellaneous Tasks and Drawings Units 9.8 Structures Quantites for EQ Report Design and Production Staffhours Comments 0 Calculated Hours 0 FBT post design proposal 10-6-23 9. Structures Summary Page 2 of 5 10/6/2023 331 Project Activity 9: Structures Summary and Miscellaneous Tasks and Drawings 16 0 0 0 0 0 0 0 16 0 Task No.Task Units No. of Units Hours per Unit Total 9.11 Field Reviews LS 1 4 4 9.12 Technical Meetings LS 1 0 0 9.13 Quality Assurance/Quality Control LS %5%1 9.14 Independent Peer Review LS 1 0 0 9.15 Supervision LS %5%1 6 9.16 Coordination LS 1 2 2 8 Units No of Units Hours/ Unit Total Hours PM Attendance at Meeting Required? Number EA 0 0 0 0 EA 0 0 0 0 EA 0 0 0 0 EA 0 0 0 0 EA 0 0 0 0 EA 0 0 0 0 EA 0 0 0 0 0 0 EA 0 0 0 - - EA 0 0 0 - - 0 0 Carries to 9.12 Carries to Tab 3 Local Governments (cities, counties) Utility Companies Other Meetings Technical Meetings BDR Coordination/Review 90/100% Comment Review Aesthetics Coordination Regulatory Agency Total Meetings Total Project Manager Meetings (carries to Tab 3) PM attendance at Phase Review Meetings is manually entered on General Task 3 PM attendance at Progress Meetings is manually entered on General Task 3 Subtotal Technical Meetings Progress Meetings (if required by FDOT) Phase Review Meetings 9. Structures - Summary and Miscellaneous Tasks and Drawings Structures Nontechnical Subtotal Structures Technical Subtotal Meetings are listed below Comments One site visit during construction Comments Coordinate with geotech, civil, City, etc. FBT post design proposal 10-6-23 9. Structures Summary Page 3 of 5 10/6/2023 332 Project Activity 17: Retaining Walls Estimator: Niedermann Tuskawilla Crossings Pond 1 Berm Failure N/A NOTE: Signature Block is optional, per District preference Task No.Task Unit No. of Units Hours/ Unit No. of Sheets Total Hours Comments General Requirements 17.1 Key Sheet Sheet 0 0 0 0 17.2 Horizontal Wall Geometry Per Wall 0 0 0 Permanent Proprietary Walls 17.3 Vertical Wall Geometry Per Wall 0 0 0 17.4 Semi-Standard Drawings Sheet 0 0 0 0 17.5 Wall Plan and Elevations (Control Drawings)Sheet 0 0 0 0 17.6 Details Sheet 0 0 0 0 Temporary Proprietary Walls 17.7 Vertical Wall Geometry Per Wall 0 0 0 17.8 Semi-Standard Drawings Sheet 0 0 0 0 17.9 Wall Plan and Elevations (Control Drawings)Sheet 0 0 0 0 17.10 Details Sheet 0 0 0 0 Cast-in-Place Retaining Walls 17.11 Design EA Design 0 0 0 17.12 Vertical Wall Geometry EA Wall 0 0 0 17.13 General Notes Sheet 0 0 0 0 17.14 Wall Plan and Elevations (Control Drawings)Sheet 0 0 0 0 17.15 Sections and Details Sheet 0 0 0 0 17.16 Reinforcing Bar List Sheet 0 0 0 0 Sheet Pile and Other Retaining Walls 17.17P Shop Drawing submittal for proposed sheet pile EACH 1 4 4 Representing Print Name Signature / Date FDOT District Consultant Name FL Bridge FBT post design proposal 10-6-23 17.Str-Retaining Walls Page 4 of 5 10/6/2023 333 Project Activity 17: Retaining Walls Task No.Task Unit No. of Units Hours/ Unit No. of Sheets Total Hours Comments 17.18P RFI's during construction EA RFI 2 2 4 17.19P Review non-conforming construction and contractor-related issues Lump Sum 1 8 1 8 17.20 N/A Sheet 0 0 0 0 17.21 N/A Sheet 0 0 0 0 1 1617. Structures - Retaining Walls Total FBT post design proposal 10-6-23 17. Str-Retaining Walls Page 5 of 5 10/6/2023 334 TUSKAWILLA CROSSINGS SUBDIVISION CITY OF WINTER SPRINGS, FLORIDA POND 1 REPAIR AND REHABILITATION Exhibit “D” Preliminary Assessment of the Pond 1 Berm Failure 335 TUSKAWILLA CROSSINGS POND 1 BERM FAILURE PRELIMINARY ASSESSMENT – September 25, 2023 Page 1 Tuskawilla Crossings Pond 1 Latitude 28.690619°, Longitude -81.259472° https://maps.app.goo.gl/3j69kTndx1PrkH9z6 Seminole County Aerial Photograph dated 2021 Pond 2 Pond 3 Pond 1 Pond 4 Berm Failure Pond 5 336 TUSKAWILLA CROSSINGS POND 1 BERM FAILURE PRELIMINARY ASSESSMENT – September 25, 2023 Page 2 1.0 – SUMMARY OF DATA COLLECTION AND REVIEW DOCUMENTS 1.1 Construction Plans ·Final Subdivision Plan for Tuskawilla Crossings Appian Engineering Plan set submitted to SJRWMD, Plotted on December 28, 2016 ·Final Subdivision Plan for Tuskawilla Crossings Appian Engineering Plan set approved by the City of Winter Springs, Plotted on May 12, 2017 ·Final Subdivision Plan for Tuskawilla Crossings Appian Engineering Record Drawings, Signed and sealed on April 25, 2019 1.2 Stormwater Management Reports ·Stormwater Management System for Tuskawilla Crossings Appian Engineering Calculations submitted to SJRWMD, Dated February 15, 2017 1.3 Geotechnical Reports ·Final Geotechnical Exploration for Tuskawilla Crossings Universal Engineering Sciences (UES) Dated October 8, 2015 ·Letter of Conformance – Materials Testing for Tuskawilla Crossings Phase 1 Sitework Universal Engineering Sciences (UES) Dated March 1, 2019 1.4 Approved Permits and Technical Staff Reports (TSRs) ·SJRWMD Approvals for Tuskawilla Crossings Permit No. 148395-1 issued on May 11, 2017 Permit No. 148395-2 issued on July 11, 2018 Permit No. 148395-3 issued on December 17, 2019 °°° 337 TUSKAWILLA CROSSINGS POND 1 BERM FAILURE PRELIMINARY ASSESSMENT – September 25, 2023 Page 3 2.0 – POSSIBLE CAUSES OF BERM FAILURE 2.1 Construction Issues and Considerations Because the berm failure appears to have occurred in the location where a drainage outfall (24-inch CMP with a contributing drainage area = 81.02 acres) previously existed, a geotechnical engineer should be retained to forensically evaluate possible construction issues that caused or contributed to the Pond 1 berm failure. Excerpt from Sheet 6 of the Specific Purpose Survey for Tuskawilla Crossings Approximate Location of the Pond 1 Berm Failure 338 TUSKAWILLA CROSSINGS POND 1 BERM FAILURE PRELIMINARY ASSESSMENT – September 25, 2023 Page 4 Drone Photograph of the Pond 1 Berm Failure taken September 1, 2023 2.2 Pond 1 Control Water Level (CWL) An excerpt from the Final Geotechnical Exploration (Section 11.0 – Stormwater Management Design) is provided below. “The sloping groundwater table was found to generally coincide with the ground surface topography. The stormwater pond designs for this site will be very challenging due to the groundwater gradient measured across the proposed pond footprints. For example, Pond 1 (Table VI-A) is expected to have seasonal high groundwater levels ranging from +32.4 (Boring P-2) at the northwest end and transitioning to +22.4 feet (Boring P-5) near the southeastern portion of the pond footprint. This represents a 10-foot elevation difference in groundwater levels across the pond footprint”. ·Estimated Seasonal High Groundwater Levels - Pond 1 Boring P-1 = 30-ft, NAVD - Pond 1 Boring P-2 = 29.9-ft, NAVD - Pond 1 Boring P-3 = 25.8-ft, NAVD - Pond 1 Boring P-4 = 18.2-ft, NAVD - Pond 1 Boring P-5 = 19.4-ft, NAVD - Pond 1 Boring P-6 = 21.4-ft, NAVD - Pond 1 Average = 24.12-ft, NAVD Water Level Gradient = 8.6-feet 339 TUSKAWILLA CROSSINGS POND 1 BERM FAILURE PRELIMINARY ASSESSMENT – September 25, 2023 Page 5 ·Estimated Normal Groundwater Levels - Pond 1 Boring P-1 = 28-ft, NAVD - Pond 1 Boring P-2 = 27.9-ft, NAVD - Pond 1 Boring P-3 = 23.8-ft, NAVD - Pond 1 Boring P-4 = 16.2-ft, NAVD - Pond 1 Boring P-5 = 17.4-ft, NAVD - Pond 1 Boring P-6 = 19.4-ft, NAVD - Pond 1 Average = 22.12-ft, NAVD ·Estimated Seasonal Low Groundwater Levels - Pond 1 Boring P-1 = 26-ft, NAVD - Pond 1 Boring P-2 = 25.9-ft, NAVD - Pond 1 Boring P-3 = 21.8-ft, NAVD - Pond 1 Boring P-4 = 14.2-ft, NAVD - Pond 1 Boring P-5 = 15.4-ft, NAVD - Pond 1 Boring P-6 = 17.4-ft, NAVD - Pond 1 Average = 20.12-ft, NAVD Excerpt from Sheet C4.12 of the Record Drawings for Tuskawilla Crossings Photographs and videos taken during site inspections conducted on September 8, 2023 and September 18, 2023 show a well-defined interface along the entire pond side slope where the sod ends and bare soil begins. Although the elevation of this sod and bare soil interface is not presently known, the sod appears to stop well above the pond control water level (CWL) as shown in the design documents. This condition would seem to indicate that Pond 1 may have been experiencing elevated water levels for an extended period of time that was sufficient to prevent any type of vegetative growth between the pond CWL and top of bank elevations. ·Elevations from the Final Plans approved by the City of Winter Springs - Pond 1 CWL = 22.60-ft, NAVD - Pond 1 Top of Bank = 26.00-ft, NAVD ·Elevations from the Final Plans approved by the City of Winter Springs - Pond 1 CWL = 22.60-ft, NAVD - Pond 5 CWL = 39.75-ft, NAVD Water Level Gradient = 8.6-feet Water Level Gradient = 8.6-feet Water Level Gradient =17.2-feet Pond 1 Section D-D 340 TUSKAWILLA CROSSINGS POND 1 BERM FAILURE PRELIMINARY ASSESSMENT – September 25, 2023 Page 6 Photograph of the Pond 1 Berm Failure Looking Northeast Additional photographs were taken during a site inspection conducted on September 13, 2023 for the specific purpose of estimating the pond static water level using field measurements for “apparent stain lines” (refer to the figure on the following page). ·Static water levels - Pond 1 CWL = 22.60-ft, NAVD (As permitted) - Pond 1 Stain Line =±24.5-ft, NAVD (field estimate) Difference =1.9-feet (22.8-inches) 341 DATENO.DESCRIPTIONREVISIONSSHEETNO.TUSKAWILLA CROSSINGS301 WEST STATE ROAD 434, SUITE 309WINTER SPRINGS, FLORIDA 32708CERTIFICATE OF AUTHORIZATION NO. 27770ENGINEER OF RECORDGREGORY A. TEAGUE, P.E.FLORIDA REGISTRATION NO. 47663CITY OF WINTER SPRINGS1126 EAST STATE ROAD 434PRELIMINARYPRELIMINARYSEPTEMBER 13, 2023TEL: 407-327-1800WEB: www.WinterSpringsFL.orgWINTER SPRINGS, FL 32708POND 1 BERM FAILURE1STATIC WATER LEVELS BASED ON FIELD MEASUREMENTSPOND 1 OVERFLOW WEIR AND BLEED DOWN STRUCTUREPOND 1 BLEED DOWN STRUCTURE AND ORIFICEPOND 1 OVERFLOW WEIR SKIMMERLEGENDX.XX<= ELEVATION IN FT, NAVD FROM THE FINAL SUBDIVISION PLAN FOR TUSKAWILLA CROSSINGS DATED MAY 12, 2017X.XX<= ELEVATION IN FT, NAVD FROM THE RECORD DRAWINGS FOR TUSKAWILLA CROSSINGS DATED APRIL 25, 2019X.XX<= ELEVATION IN FT, NAVD DERIVED FROM FIELD MEASUREMENTS FOR TUSKAWILLA CROSSINGS TAKEN ON SEPTEMBER 13, 2023EL. ±26.0POND TOP OF BANKSKIMMERCREST EL. ±24.0OVERFLOW WEIRTOP EL. 26.06DITCH BOTTOM INLETTOP EL. 26.13FILTRATION SYSTEMNUTRIENT REMOVALPOND 1TOP EL. 26.13STRUCTURE NRFS-240.5" 19" 21.5"6" PVC TEE6" ORIFICEORIFICE INV EL. ±22.8ORIFICE INV EL. 22.60SKIMMER BOTTOM EL. 21.62STAIN LINE EL. ±24.5SKIMMER TOP EL. 25.30SKIMMEROVERFLOW WEIREL. ±24.5STAIN LINECONTROL WATER LEVELSTAIN LINE EL. ±24.5STATIC WATER LEVEL342 TUSKAWILLA CROSSINGS POND 1 BERM FAILURE PRELIMINARY ASSESSMENT – September 25, 2023 Page 8 Photographs taken during a site inspection conducted by City staff on September 21, 2023 show that the circular orifice at Structure NRFS-2 (Nutrient Removing Filtration System) was clogged by what appears to be plastic erosion mat that may have been incorrectly installed on the pond side slopes. Photograph of the NRFS-2 Orifice Clogged with Plastic Erosion Mat 343 TUSKAWILLA CROSSINGS POND 1 BERM FAILURE PRELIMINARY ASSESSMENT – September 25, 2023 Page 9 2.3 Pond 1 Retention Volume Recovery Retention volume recovery is provided by a circular orifice and a biosportion activated media (BAM) filter at Structure NRFS-2 (Nutrient Removing Filtration System), with discharge provided by a 12-inch outfall pipe. If the BAM filter was clogged and little flow was occurring, an elevated CWL of approximately 25-ft, NAVD could be anticipated, or a water level that is roughly 1-foot below the pond top of bank. ·Elevations from the Record Drawings prepared by Appian Engineering - 6-inch diameter PVC tee bottom = 22.34-ft, NAVD - 6-inch diameter orifice invert = 22.60-ft, NAVD - Top of 4-inch baffle (BAM filter overflow) = 24.93-ft, NAVD Excerpt from Sheet C7.12 of the Record Drawings for Tuskawilla Crossings This is actually the bottom of the PVC tee This details shows a 6- inch orifice invert at EL. 22.60-ft, NAVD Pond 1 344 TUSKAWILLA CROSSINGS POND 1 BERM FAILURE PRELIMINARY ASSESSMENT – September 25, 2023 Page 10 Excerpt from Sheet C11.3 of the Record Drawings for Tuskawilla Crossings 2.4 Pond 1 Overflow Weir Overflow of peak discharge rates is provided by a 2-step concrete weir, with a 30-foot wide overflow at elevation 24-ft, NAVD and an 80-foot wide overflow at elevation 25.2-ft, NAVD. Although as-built information for the overflow weir was not shown in the Record Drawings, overflow at elevation 24-ft, NAVD is approximately 2-feet below the pond top of bank at elevation 26-ft-NAVD, a vertical distance which should be sufficient to mitigate the possibility of having a weir crest elevation that is at or above the pond top of bank. If the fiberglass skimmer was not installed correctly, or if the vertical distance provided between the skimmer bottom and the pond side slope was insufficient, water levels in the pond would need to exceed elevation 25.3-ft, NAVD (skimmer top) before discharge could occur. Excerpt from Sheet C11.0 of the Record Drawings for Tuskawilla Crossings (This detail does not match the Pond 1 Skimmer Detail shown on the next page) Top of 4-inch baffle Invert of 6-inch orifice Structure NRFS-2 Overflow Weir #1 Overflow Weir #2 Observations during the site inspections indicate that a 2-step concrete weir was not constructed 345 TUSKAWILLA CROSSINGS POND 1 BERM FAILURE PRELIMINARY ASSESSMENT – September 25, 2023 Page 11 Observations during a second site inspection conducted on September 13, 2023 confirm that the fiberglass skimmer for the Pond 1 overflow weir has been damaged, which may or may not have happened at the same time as the berm failure (refer to the previous figure). Excerpt from Sheet C11.0 of the Record Drawings for Tuskawilla Crossings Water flow area Skimmer top Skimmer bottom Contributing drainage area = 42.65 acres 346 TUSKAWILLA CROSSINGS POND 1 BERM FAILURE PRELIMINARY ASSESSMENT – September 25, 2023 Page 12 2.5 Groundwater Inflows Photographs and videos taken during site inspections conducted on September 8, 2023 and September 18, 2023 show perforated HDPE pipes that appear to be some type of underdrain. One segment of broken pipe located near the berm failure was observed to be flowing water during the site inspections, whereas segments of pipe at other locations within the pond were observed to not be flowing water during the site inspections. The locations and horizontal limits of all the HDPE pipes still need to be determined, along with the origin of the piping system and the type of flow that the system is intercepting (groundwater baseflow, flowing artesian well, etc.). Screen Capture from a Video of the Flowing Underdrain Pipe near the Berm Failure °°° Damaged Perforated HDPE Pipes 347 TUSKAWILLA CROSSINGS POND 1 BERM FAILURE PRELIMINARY ASSESSMENT – September 25, 2023 Page 13 3.0 – RECOMMENDATIONS 3.1 Geotechnical Investigations A geotechnical engineer should be retained to: ·Determine the locations and horizontal limits of all the perforated HDPE pipes and develop a protocol for repairing the damaged sections or plugging the pipes. ·Forensically evaluate possible construction issues that caused or contributed to the Pond 1 berm failure and develop specific recommendations for re-constructing the damaged berm. A proposal from Devo Engineering was requested on Friday, September 22, 2023. 3.2 Topographic Survey A professional land surveyor should be retained to: ·Horizontally locate the perforated HDPE underdrain pipes. ·Horizontally and vertically locate the geotechnical soil borings. ·Develop a topographic survey for Pond 1. The topographic survey will be used to prepare construction plans to illustrate: the berm failure repair; re-grading the pond side slopes; the limits where high performance turf reinforcement mats need to be installed. A proposal from Southeastern Surveying was requested on Friday, September 22, 2023. 3.3 SJRWMD Permit Coordination Coordinate with District staff relative to the possibility of removing Structure NRFS-2 (Nutrient Removing Filtration System) due to maintenance issues that could have contributed to the Pond 1 berm failure. 3.4 Bid Documents Prepare bid documents: ·Construction plans. ·Technical specifications (including geotechnical engineering recommendations). ·Bid schedule. 3.5 Bidding and Construction of the Proposed Repairs and/or Improvements Request bids from contractors and schedule a mandatory pre-bid meeting at the project location. °°° 348