These Lake Hancock projects have played a critical role in the District’s recovery plan for the Upper Peace River.
Lake Hancock
Lake Hancock is one of the largest lakes in Polk County. It encompasses more than 4,500 acres and is in the headwaters of the Peace River, which flows 120 miles south to Charlotte Harbor. As part of the Upper Peace River watershed, the lake has ecological importance throughout southwest Florida.
Background
Over the last 150 years, the cumulative effects of land use and water withdrawals have altered the hydrology of the Upper Peace River watershed. These activities have significantly reduced the watershed’s ability to store rainfall and recharge, which, in combination with groundwater withdrawals, has resulted in lower local and regional groundwater levels, extended periods of low or nonexistent river flows in the Upper Peace River (from Bartow to Zolfo Springs) during the dry months, degraded water quality and altered ecosystems.
Lake Level Modification Project
The Lake Level Modification Project raised the water control elevation of the existing outflow structure on Lake Hancock, Structure P-11. This increased the water storage capacity of the lake. Water stored in the lake can be slowly released during the dry season to help meet the minimum flow requirements in the Upper Peace River, which is the portion of the river between Bartow and Zolfo Springs. The structure is located on Saddle Creek in Bartow and is remotely operated.
Construction on the project began in November 2011 and was completed in April 2013. The project involved replacing the P-11 Water Conservation Structure that was built in 1963 with a new structure that allows the District to maintain higher lake levels. This increased the elevation from 98.7 feet above sea level to 100 feet (NGVD 29). The normal operating level of 100 feet was determined to be the approximate historical level of the lake, before the area was mined for phosphate and the natural lake outlet deepened.
Outfall Treatment Project
The Outfall Treatment Project was designed to help improve the quality of the water discharging from Lake Hancock into the Peace River. Water discharging from Lake Hancock is treated when it flows through large areas of wetland vegetation that removes nutrients and other pollutants before the water enters the Peace River. This helps improve the water quality in the Peace River and Charlotte Harbor.
Construction of the wetland treatment system began in September 2011 and was completed in June 2014. The wetland treatment system is approximately 1,000-acres and was built on part of the 3,500-acre parcel of land formerly known as Old Florida Plantation.