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HomeMy WebLinkAboutItem #15 Approval of Lake Prima Vista Nutrient and Hydrologic Management Plan with Amec Foster Wheeler t I ocoee florida AGENDA ITEM COVER SHEET Meeting Date: December 6, 2016 Item # /5 Reviewed By: Contact Name: Stephen C. Krug Department Director: /i'_ Contact Number: 6002 City Manager: Subject: Lake Prima Vista Nutrient and Hydrological Management Plan with Amec Foster Wheeler. Commissioner Wilsen, District 2. Background Summary: The Public Works Stormwater Division, the Florida Fish and Wildlife Conservation Commission (FWC), along with adjacent residents, have observed a visible change in the water quality of Lake Prima Vista over the last two years. The City participates in the University of Florida's volunteer Lakewatch water quality monitoring program to determine the health of the City's lakes. Utilizing the Lakewatch data, Lake Prima Vista has recently been labeled an "Impaired Water" by the Florida Department of Environmental Protection (FDEP) due to elevated nutrient concentrations. Working with FWC, FDEP, St. Johns River Water Management District and other municipalities who have experienced similar impairment issues, it was determined the City needed to secure the services of a firm which specializes in environmental restoration measures. The unique nature of the nutrient loading requires specialized testing to determine corrective action. Public Works contacted reputable environmental firms and testing labs to solicit interest in performing the specialized testing. The firms and labs contacted did not perform the required testing or directed Public Works to a firm able to provide the requested testing and analysis; Amec Foster Wheeler Environmental & Infrastructure, Inc., (Amec). Amec was recommended by peers, along with other Municipalities and Environmental Firms for their qualifications and expertise to sample, evaluate and determine the required corrective actions. Amec has current contracts with Orange County for lake management, Seminole County for stormwater management and permitting along with continuing services contracts with the Lake County Water Authority and City of Maitland. The Amec team has local experience with similar issues, particularly with the Lake County Water Authority on the chain of lakes taking effluent from Lake Apopka. Amec also has an unrelated continuing contract with Ocoee for surveying and mapping. Public Works has met with Amec to derive a detailed sampling program in order to create a water quality improvement plan with a projected fourteen (14) month completion time. Public Works recommends waiving the formal bid process for this specialized environmental work and issuing a purchase order to Amec to proactively determine the nutrient loading source and corrective actions required to maintain Lake Prima Vista as a healthy water body. Public Works has been in contact other municipalities to verify the pricing is in line with the scope of work and the $62,297.19 negotiated for these services fall within industry standards and is adequately funded in the Stormwater Division. Issue: Contract with Amec Foster Wheeler Environmental & Infrastructure, Inc., for the Lake Prima Vista Nutrient and Hydrological Budget and Management Plan. Recommendations: Recommend approval to issue a purchase order to Amec Foster Wheeler Environmental & Infrastructure, Inc., for the Lake Prima Vista Nutrient and Hydrological Budget and Management Plan for a not to exceed amount of $62,297.19 and authorize the City Manager to approve and execute change orders to the work in accordance with the limits established in the Purchasing Code. Attachments: Amec Foster Wheeler Task Proposal Financial Impact: The work is adequately funded in the Stormwater Division budget for miscellaneous projects. Type of Item: (please mark with an 'V) Public Hearing For Clerk's Dept Use: Ordinance First Reading X Consent Agenda Ordinance Second Reading Public Hearing Resolution Regular Agenda X Commission Approval Discussion&Direction Original Document/Contract Attached for Execution by City Clerk Original Document/Contract Held by Department for Execution Reviewed by City Attorney N/A Reviewed by Finance Dept. N/A Review ed by ( ) N/A 2 November 17, 2016 amec wiLY foster wheeler Mr. Richard Campanale Streets and Traffic Operations Manager City of Ocoee 301 Maguire Road Ocoee, FL 34761 Re: Amec Foster Wheeler Task Authorization Lake Prima Vista Nutrient and Hydrologic Budget and Management Plan Amec Foster Wheeler Project No. 600449.3 Dear Mr. Campanale: Lake Prima Vista OA/BID 3002E) has been identified as an impaired water due to elevated nutrient concentrations pursuant to Chapter 62-303, FAC. Lake Prima Vista is part of the Middle St. Johns River Basin within the Wekiva River Planning Unit, and is connected by a navigable channel to Starke Lake which is also impaired. The City of Ocoee desires to evaluate hydrologic and nutrient budgets for Lake Prima Vista and potential external and internal load reduction efforts to support water quality restoration within the lake. The City's efforts to restore water quality within Lake Prima Vista will also be integral to the Florida Department of Environmental Protection's (FDEP's)Wekiva River Basin Management Action Plan (BMAP)adopted in 2015. The proposed study of Lake Prima Vista will assist the City with determining the level of effort required to restore the lake to meet its Class Ill designated use as"swimmable"and "fishable". the City has requested Amec Foster Wheeler Environment 8 Infrastructure, Inc. (Amec Foster Wheeler) prepare the following Scope of Services to perform a nutrient loading assessment and lake management plan. Lake Prima Vista does not have an existing Total Maximum Daily Load (TMDL) therefore the City desires to develop site-specific hydrologic and nutrient budgets for the lake, including an assessment of internal loading. The purpose of the study and lake management plan is to determine the extent of impairment and to identify specific areas within the Lake Prima Vista basin where nutrient load reductions could be achieved. Hydrologic and nutrient budgets will be developed for Lake Prima Vista to identify significant pollution sources and to provide a ranking of areas with respect to annual mass loadings and areal loadings. Specific nutrient load reduction projects will be recommended to reduce pollutants entering Lake Prima Vista. All field work performed by Amec Foster Wheeler will conform to the FDEP's Standard Operating Procedures for Field Activities, DEP-SOP-001/01, March 1, 2014, and effective July 7, 2014. All laboratory analyses will be conducted pursuant to Chapter 62-160, FAC. Specific work efforts to be performed to achieve these objectives are outlined below. Amec Foster Wheeler Environment B Infrastructure,Inc. 2000 E.Edgewood Dive,Suite 215 Lakeland.Florida 33603 Tel (863)667-2345 Fax (863)667-2862 www.amecfw.com Amec Foster Wheeler shall, at a minimum, perform the following specific tasks for the Lake Prima Vista project: TASK 1 - ATTEND PROJECT KICK-OFF MEETING Representatives of Amec Foster Wheeler will attend a project start-up meeting with representatives of the City to review the overall project objectives, the scope of services, and the project schedule. Copies of all previous water quality investigations and data, engineering studies, and other information related to Lake Prima Vista and the surrounding watershed areas, will be provided to Amec Foster Wheeler by the City. The City will provide locations (in ArcGIS format if possible) for stormwater structures and BMPs draining to Lake Prima Vista. Task 1 Total: $492.00 TASK 2- REVIEW AVAILABLE DATA Data provided to Amec Foster Wheeler at the project start-up meeting will be reviewed and summarized for potential use in developing hydrologic and nutrient budgets for the lake, as well as a nutrient management plan for improving water quality conditions. Amec Foster Wheeler will also seek and utilize, as necessary, additional data relevant to the work effort not otherwise provided by the City, which may be available through the Lakewatch or STORET databases. Available water quality data will be entered into a statistical database, and both long term (period of record) and short term (past ten years) trend analyses will be performed to identify significant water quality trends for typical nutrient components including but not limited to TP, TN, NO3, NO2, chlorophyll-a and Secchi disk depth. Geometric means will be calculated for TN and TP and will be evaluated based on Numeric Nutrient Criteria (NNC). TN/TP ratios and TSI values will be developed to support the limnological analyses. Available historical algal speciation data will be included in the analysis. Task 2 Total: $2,381.50 TASK 3- DELINEATE SUB-BASINS AND ID BMPS Amec Foster Wheeler will delineate the Lake Prima Vista watershed sub-basins. The drainage basin area will be summarized for all sub-basins in both graphical and tabular formats. Amec Foster Wheeler will field verify the sub-basin delineations and existing structure information provided by the City. Task 3 Total: $3,621.50 TASK 4- ESTIMATE ANNUAL RUNOFF INPUTS Estimates of annual runoff inputs to Lake Prima Vista from each of the contributing watershed areas will be developed using computer spreadsheet modeling techniques. The modeling will be performed using site-specific hydrologic characteristics for each drainage sub-basin area, including basin size, percentage of impervious areas, land use, soil characteristics, and conveyance system types. Estimates of annual runoff inputs to the lake will be generated for each contributing sub- basin area. Task 4 Total: $2,357.50 1 of Ocme F rP:i_aye J ] rash Auti a;tan Nryerci .16 v TASK 5- EVALUATE SEEPAGE AND INTERNAL LOADING Amec Foster Wheeler will perform the following tasks: a. Installation of seepage meters: Amec Foster Wheeler will install up to four groundwater seepage meters in Lake Prima Vista to determine the quality and quantity of shallow groundwater seepage entering the lake. Based on the paper "Estimation of Downward Leekage in Florida Lakes" by Deevey (1988) the vast majority of seepage in Florida lakes occurs within 30 meters of the shoreline. Therefore it is assumed that seepage meters can be installed in near-shore areas of the lake not requiring SCUBA. The areas for installation of seepage meters will be selected jointly by Amec Foster Wheeler and the City and should maximize the range of land use and topographic characteristics in upland areas adjacent to the seepage meters. If possible, the seepage meters will be installed in areas with and without septic tanks in an attempt to identify possible contributions from septic tank areas, if relevant. Once installed, seepage meters will remain open to the water column for the first week to allow equalization. If organic sediments are present, they will not be removed prior to installation of the seepage meters as this may have a significant impact on seepage collection. b. Routine monitoring of seepage meters: The four seepage meters installed as a part of Task 6a and will be sampled approximately every two months, or as needed,for a period of up to one year for a total of up to 6 sampling events. During each collection event, the quantity of seepage collected in each seepage meter will be measured, and samples of water collected from the seepage meters will be returned to the laboratory for chemical analysis. A total of 24 sets of water samples collected from the seepage meters will be analyzed for the following parameters: (1) pH (5)Total IGeldahl Nitrogen (2) Specific Conductivity (6)Total Nitrogen (3) Total Ammonia Nitrogen (7) Orthophosphate (4) NOx(nitrite+ nitrate) (8)Total Phosphorus c. Determine sediment P speciation: Amec Foster Wheeler will collect four core samples from locations selected jointly with the City. Amec Foster Wheeler will deliver samples to DB Environmental, Inc. for modified Chang and Jackson analysis. The analysis will be presented in tabular format and will include the following parameters: (1) Saloid-bound and exchangeable Ca (4) Reductant phosphate (2) Aluminum phosphate (5) Calcium phosphate (3) Iron phosphate (6) Total phosphorus This data will be used to evaluate sediment phosphorus that could become biologically available. This information is also necessary for determining proper chemical application rates for sediment inactivation alternatives that may be recommended as part of Task 9. (My cf Oc •_ atOI L_ Pa r VNJO. N ununt I, .. P -�, t , , •e,-. ,,I,- . d. Sediment core incubation: Sediment core incubation provides the ability to directly measure nutrient flux (internal loading) from lake sediment in a laboratory environment. Two intact cores will be collected from each of two locations in Lake Prima Vista and transported to the Amec Foster Wheeler Gainesville laboratory for incubation. Cores from each location will be incubated in oxic and anoxic conditions over a period of 6 days and will be sampled at 0, 2, 4, and 6 day intervals. A total of 16 sets of water samples will be analyzed for the following parameters: (1) Total Kjeldahl Nitrogen (1)Total Nitrogen (3) Total Ammonia Nitrogen (4) Orthophosphate (5) Total Phosphorus Task 5 Total: $29,677.69 TASK 6- DEVELOP HYDROLOGIC BUDGET A hydrologic budget will be developed, by sub-basin, for Lake Prima Vista based upon evaluated inputs from direct precipitation, stormwater runoff (Task 4), and groundwater seepage (Task 5). The results of the hydrologic budget will be presented in both graphical and tabular formats. Potential inputs from Starke Lake due to seiche effect will not be included in this analysis. Task 6 Total: $2,424.00 TASK 7- DEVELOP NUTRIENT BUDGET A nutrient budget will be developed for Lake Prima Vista using the hydrologic budget developed in Task 8 and available literature-based concentrations for various hydrologic inputs (e.g., aerial deposition from literature values and Event Mean Concentration for specific land uses). Nutrient inputs from seepage will be calculated using the data obtained in Task 5b. Internal loading will be estimated using the data obtained in Task 5d. The budget will account for existing BMPs and calculations of the existing nutrient load reductions. The budget will also estimate the loading from septic, sewer, and reclaimed water sources if any are present. The results of the nutrient budget will be presented in both graphical and tabular formats. Potential inputs from Starke Lake due to seiche effect will not be included in this analysis. Task 7 Total: $1,741.50 TASK 8- DEVELOP TOTAL AND MUCK DEPTH PROFILES We understand that there is a requirement to determine the approximate elevations, depths and quantities of unconsolidated sediment in Lake Prima Vista, a 25 acre lake located in the City of Ocoee that connects to Starke Lake. This will require the horizontal and vertical locations of the lake bottom and the location and elevation of the top of the sediment interface. From there mapping and approximate quantities can be developed to meet project needs. We propose to meet this requirement utilizing traditional survey methodologies. The majority of the lake, to include only the open water areas to the edges of shoreline vegetation, would be surveyed by physically sounding and probing the sediment thickness at 120-150 locations using t Once= /n, Y<Ye PiJi.ed No 9,. 11 :_ I - L✓-PI N'I< -i .. i h , - " Fa' Fr_s4 an approximate 100' grid around the lake using a 2" diameter PVC sounding pole with foot.. The sounding pole will be vertically lowered at the selected location until it comes in contact with the top of the sediment interface. A depth below water level at the foot of the pole will be recorded. The sounding pole will then be pushed down to refusal to provide an approximate lake bottom elevation. Another depth measurement will be recorded. The difference in the depths is the approximate sediment thickness at that particular location. Upon completing the data collection we would process the data and produce final deliverable products to consist of topographic maps depicting the approximate lake bottom elevations and contours, the approximate sediment interface elevations and contours and resultant approximate quantity of existing sediment. Horizontal datum will be NAD83/2011 and vertical datum will be NAVD8S. All work will be performed in conformance with Florida Administrative Code Rule Chapter 5J-17, pursuant to Chapter 472, Florida Statutes. Task 8 Total: $6,144.00 TASK 9 - EVALUATE ALTERNATIVES FOR WATER QUALITY IMPROVEMENT Appropriate in-lake treatments and watershed BMPs will be identified and ranked. This proposal assumes three alternatives. Estimated costs (including land costs, design, construction and Operation and Maintenance) for each high ranking BMP will be presented, along with anticipated water quality benefits. Cost efficiencies will be developed for each alternative for a 20-year life cycle. Additional non-structural alternatives will be reviewed and included as appropriate, but at a minimum will include compliance with relevant fertilizer ordinances, regular maintenance of septic tanks and drainfields and relevant components of the Florida Yards and Neighborhoods Homeowner Program. Task 9 Total: $4,677.50 TASK 10- PREPARE DRAFT FINAL REPORT A Draft Final Report will be prepared which presents the results of the previous tasks. Two hard copies and one electronic copy of the Draft Final Report will be submitted to the City for review. All Chain-of-Custody forms, laboratory reports, and field data sheets will be provided. Task 10 Total: $7,030.00 TASK 11 - PREPARE FINAL REPORT After receiving comments from the City, a Final Report will be prepared for the project. Two hard copies and one electronic copy of the Final Report will be submitted to the City. Task 11 Total: $1,750.00 Lump Sum for Scope of Services $62,297.19 City cro.:rc l--k ALPI' .a ,.. L Pnr t _ H ,jl_ P 'Inr. P Time to Completion The time to completion will be 14 months following Notice to Proceed. If you have any questions please don't hesitate to contact us Sincerely, Amec Foster Wheeler Environment&Infrastructure, Inc. Lance Lumbard Scott C.Wuitschick, PE Project Manager Practice Leader-Water Resources LL/SCW:jrb