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Lake Gibson is a 489 acre natural lake located in north Lakeland, FL with a shoreline that is shared by the City of Lakeland and Imperial Polk County. Gibson is Lakeland’s healthiest urban lake based on its water clarity, lack of a muck bottom and a well-balanced animal community. However, this condition is threatened by the stormwater runoff that carries excess nutrients and other pollutants directly to the lake every time it rains.
A study conducted by the City of Lakeland in cooperation with the Southwest Florida Water Management District (SWFWMD) found that the 245-acre southwest sub-basin (see red-lined boundary above in aerial photograph) is a significant source of urban pollutants. A large percent of this area is covered by rooftops, blacktop, and concrete that won’t allow the rain to naturally soak into the ground. This is where nutrients are used by plants and microbes and some pollutants are reduced before the water reaches Lake Gibson. This watershed includes the Lakeland Mall, US Hwy 98 North, and numerous large commercial properties. Stormwater drained from these properties flows into an urbanized stream located east of US Hwy 98 N. Large flows of water after storm events carry nutrients, pollutants, and sediment into the creek then into Lake Gibson. Stormwater management is further complicated by a portion of the stream having very steep banks. The affects of this stormwater flow on the stream and lake are evident by the highly eroded stream banks and the sediment delta forming at the point the stream flows into Lake Gibson.
To address this problem, the City of Lakeland once again partnered with SWFWMD to upgrade and build new stormwater management systems. The project, called the Lake Gibson Southwest Stormwater Retrofit, is engineered to treat the stormwater for both quantity and quality.
The project is funded by the City of Lakeland through the Stormwater Utility fees and cooperative funding from the SWFWMD. When completed, this stormwater management system will benefit this urbanized natural lake and the citizens of Lakeland by improving Lake Gibson’s water quality, recreational value, and fish and wildlife habitats.
The project has been organized into phases and includes, project design, regulatory permitting, land acquisition, construction, and maintenance.
The initial phase of the project included locating the source of pollutants (nutrients, dissolved metals, and sediment) to Lake Gibson. The next step was determining which stormwater management retrofit design would best address the unique onsite conditions. The design had to address stormwater quantity and quality in order to reduce the potential for flooding and pollutants.
The best design determined for the sub-basin consists of constructing stormwater management ponds along-side the existing creek that carries stormwater to the lake. Most of the stormwater runoff would be directed out of the creek and into these ponds where the water is stored and the pollutants removed. These ponds will reduce the high stormwater flows moving through the creek by providing more time for attenuation and water quality treatment. The stored water is then returned to the creek slowly over a longer period of time cleaner and with less potential for flooding. The locations and functions of the three stormwater management ponds, Sites 1 to 3, are discussed in detail below:
Site 1 is 4.7 acres and located south of Cassandra Lane and east of Corporate Avenue. The land was purchased from Carpenters Home Estate and Without Walls International. It is near the mouth of stream as it enters Lake Gibson. This site will treat stormwater generated within a 54 acre area. The stormwater will be diverted into a constructed settling pond then sheet flow over a spreader swale into an existing wetland. Currently, the existing wetland is in poor condition and will benefit from the project. The wetland will treat the stormwater and the stormwater will slowly percolate into the groundwater or the stream.
Site 2 is 4.4 acres and located immediately south Carpenters Way and west of the stream. This site is upstream of Site 1 and adjacent Site 3. The site will attenuate and treat stormwater generated within a 56 acre area. The stormwater will be diverted into an existing pond modified into an attenuation pond then flow into a created wetland marsh system for water quality treatment. The treated stormwater will slowly discharge into the stream.
Site 3 is 5.9 acres and located south of Carpenters Way and east of the stream. The land purchased from Without Walls International and Life Church @ Auburndale. This site is upstream of Site 1 and adjacent to Site 2. The site will attenuate and treat stormwater generated in a 67 acre area. The stormwater will be diverted into a constructed attenuation pond then flow into a created wetland marsh system for water quality treatment. The treated stormwater will slowly discharge into the stream.
The created marshes will be planted with wetland species that are native to the area. The plantings will be planned to provide ease of maintenance, water quality treatment and visual beauty. Once the project is completed the stormwater treatment ponds will require periodic maintenance that includes dredging, harvesting and replanting as needed. The goal of the project and the ongoing maintenance is both function and form; the system should perform well and add to the scenic beauty of the area.
Project Progress
Project design - Completed 2007
Regulatory permitting – Permit issued by SWFWMD May 2008.
Land purchasing – Completed at all three sites from 2008 to 2009.
Project Bidding –
* Pre-Bid Meeting Held - 10:00 AM October 13, 2009
* Bids Due - 2:00 PM November 3, 2009
* Contract Award - December 7, 2009 (projected)
Link to Purchasing
Click for Project Construction Drawings
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ADDENDUM #1 (New - October 27, 2009)
All items can be downloaded from the FTP site - instructions below.
Addendum Narrative
Revised Drawings
CAD Drawings (Download Instructions for FTP Site)
Aerial Photographs
Ingress/Egress Easement Details
Revised Unit Price Bid Sheet
Revised Measurements and Payment Section 01150
Revised Quality Control Services
Click for Geotechnical Reports Site 1 Site 2 Site 3
Construction – Not started yet.
Maintenance - Conducted on a regular basis.
More information
To get more information about Lake Gibson and other lakes in Lakeland, FL., click on the link below to visit the “Overview of Lakes” page of the Lakes & Stormwater Division.
Lakeland Lakes Overview
You may contact Douglas Gleckler, Manager for Lakes & Stormwater Division, at 863-834-8439.
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