MANASOTA & PEACE RIVER BBDs Meeting Notebook 10-21-09.docx

L770
Lk Gibson Stormwater Mgmt System Retrofit
Project Type Cooperative Funding
AOR(s)
Flood Protection, Water Quality
Basin(s) Peace River
Cooperator(s)
City of Lakeland
Project Manager ZAJAC, CHRIS
Task Manager(s)
Status Ongoing
Description
This project involves the engineering design, permitting, and construction to retrofit the stormwater management
system of Lake Gibson's southwest drainage sub-basin. In 2004, the City of Lakeland received funding from the Peace
River Basin Board (L145 - Lake Gibson Southwest Area: Watershed Management Plan) to conduct a diagnostic
evaluation of the southwest basin to identify the sources of erosion, pollutant loading and flooding. One task in the
evaluation was the design of conceptual plan options to address the issues noted above. The City has chosen one of
the conceptual plan options and has decided to move forward with final design, permitting and construction. The
conceptual plan option that was chosen involves the construction of three wet detention ponds designed to capture
and treat stormwater prior to discharging into the existing conveyance stream which discharges to Lake Gibson. The
design will include components that will reduce peak flows and enhance base flows through storage and release,
provide water quality treatment using treatment wetlands, and reduce flooding through attenuation and downstream
channel restoration. Due to the complexity of the project, it is anticipated that the design and permitting phase will take
approximately nine months to one year to complete. Land acquisition and construction will take approximately three
years to complete. All lands acquired will be used solely for the proposed project. The FY2007 project deliverables will
include sealed construction plans and specifications for all project elements, bid documents and all necessary
state/federal permits. Construction is scheduled to occur in FY2008, FY2009 and FY2010.
Benefits
The design will include components that will reduce peak flows and enhance base flows through storage and release,
provide water quality treatment using treatment wetlands, and reduce flooding through attenuation and downstream
channel restoration. The project will treat stormwater from 245 acres of highly urbanized land.
Costs
The total project cost for design, permitting, land acquisition and construction is $4,650,000. The FY2007 cost for
design and permitting is $150,000. The Peace River Basin Board has approved funding in the amount of $75,000 in
FY2007 while the City will fund the remaining $75,000. The Peace River Basin Board has budgeted $562,500 and
$187,632 respectively in FY2008 and FY2009. The cooperator will contribute $750,000 for each FY2008 and FY2009.
Due to budgetary constraints the Peace River Basin Board only included $187,632 in its FY2009 budget for this
project. Because of this, the total funding amount shown in the table does not match the total project cost. In FY2010
the cooperator is requesting the Peace River Basin Board fund $937,500 while the cooperator will fund $937,500. Due
to budgetary constraints the Peace River Basin Board only included $200,000 in its FY2010 budget for this project.
The District funding amounts shown in the table include staff salaries, travel and central garage charges.
Additional Information
Lake Gibson is a 489-acre headwater lake in the Peace River Basin. Lake Gibson flows into Lake Parker which
discharges into Lake Hancock via Saddle Creek. Lake Gibson is included on the Florida Department of Environmental
Protection verified list as being impaired for nutrients. The southwest sub-basin of Lake Gibson is 245 acres of highly
urbanized land. This sub-basin includes portions of the Lakeland Mall, US 98 North and a variety of large commercial
properties. A deeply incised creek conveys surface flows from the sub-basin to Lake Gibson. Slopes along the creek
are moderate to severe. The extensive development of land and the associated impervious cover has greatly
increased the peak run-off rates and volumes, and reduced base flow through the creek. This has resulted in erosion
of the stream channel with the deposition of eroded sediments in Lake Gibson, as well as flooding of some
downstream residential properties. A large sediment delta has formed at the confluence of the stream and lake.
Stormwater run-off quality has been sampled and is characterized as poor. Although the southwest sub-basin is
relatively small in size, this tributary to Lake Gibson is a significant source of pollutant loading to the lake. Correcting
the deficiencies in this basin will be an important first step in addressing nutrient enrichment impairment of Lake
Gibson.
020 - Peace River Basin 296