Aquifer Recharge at Flatford Swamp

This project will investigate the recharging of excess surface water, treated to primary drinking water standards, into the Upper Floridan aquifer more than 1,000 feet below the land’s surface. The recharged water will help improve groundwater levels and reduce the rate of saltwater intrusion from the Gulf of Mexico in the SWUCA’s Most Impacted Area.

SWUCA Recovery and Natural System Improvement

In 2017, the District conducted a feasibility study at Flatford Swamp in Manatee County that evaluated an aquifer recharge project using up to two million gallons a day (mgd) of excess surface water draining into Flatford Swamp.

The fully operational Flatford Swamp project (future build-out of 3 to 4 wells) may help recover groundwater levels by recharging up to 10 mgd in the Most Impacted Area of the SWUCA, reducing the rate of saltwater intrusion. Another benefit of removing water from the swamp is it will help restore the swamp’s natural hydrologic period and vegetation patterns.

Staff plans to implement a step-by-step analysis conducting additional data collection, monitoring and computer modeling to ensure the project concept is thoroughly evaluated.

The current pilot study of the surface water recharging will act as a small-scale version of the recharge project. 

The recharge project will be implemented only if it is found to be safe for the water resources and beneficial for groundwater levels.

Project Details

In January 2017, the District held a public meeting prior to FDEP’s issuance of a permit. In April 2017, the District’s Governing Board unanimously approved the project. During late 2017 and early 2018, staff worked on sampling the source water as well as retaining a consultant engineer and a driller.

During the stakeholder engagement process, the District received inquiries from the agricultural community about water quality. In coordination with the UF/IFAS Plant Diagnostic Center, District staff confirmed that there was no presence of Phytophthora, a mold that could impact certain agricultural crops, in the surface water. Testing continued twice a year for approximately four years. Considering continuous negative results, phytophthora sampling stopped at the end of 2021.  

Rowe Drilling conducted drilling on all four wells at the Flatford site. Drilling of the final well was completed in April of 2019. Jones Edmonds completed the design of the diversion infrastructure and TLC Diversified began construction in August 2020

The majority of the construction of the diversion infrastructure was complete in September 2021. This includes the installation of the borehole control valve, and construction of the intake structure, recharge building, recharge pump and chemical feed shed. Development of the DEP UIC permit extension request is underway. Following May 2021 permitting discussions with DEP, staff is currently looking at implementing the new treatment concept to the use of chloramines for additional disinfection. Construction of this new system will begin early 2022 and be complete in summer.

Planning of the operational testing phase has begun. Testing will begin when the site is operational and will look at water quality at the monitor wells.

A wetland monitoring project is being conducted by District staff to track any changes to hydrology and vegetation that may be caused by the recharge well operation.   

The District will continue to work with key stakeholders and potentially affected parties. Please contact the project manager or technical lead with any questions.

Project Schedule

Step 1: Desktop and modeling evaluation. Permit test well. – Complete

Step 2: Drill test and monitor wells. Collect aquifer characteristics and water quality. – Complete

Step 3: Conduct pilot study and construct diversion infrastructure. – Complete

Step 4: Construct disinfection system. – Mid 2022

Step 5: Begin recharge surface water test. Continue appropriate testing. – Mid 2022

Step 6: Evaluate all testing results. – 2023

Project Updates

March

  • Monitoring construction of chloramine system.
  • Quarterly wetland monitoring  near test well site.
  • Continued monitoring UIC renewal with FDEP.
  • Continued water quality sampling of Myakka River surface water to assist with chemical use.
  • Staff present at the MRMCC meeting.
  • Concrete and SCADA control work began on site.

  April

  • Monitoring construction of chloramine system.
  • Continue water quality sampling of surface water to assist with chemical use.
  • Internal training on operational testing.
  • Staff present at Environmental Advisory Committee.

Projected May

  • Initiate performance testing following completion of electrical and chemical equipment installation.
  • Continue training staff on operational testing procedures.
  • Continue water quality sampling of surface water to assist with chemical use.
  • Expected to complete new chemical equipment and begin electrical work.