For a milestone 20th year, water flowing from farmlands in the Everglades Agricultural Area achieved phosphorus reductions that significantly exceed those required by Florida's Everglades Forever Act.
Implementation of improved farming techniques under the SFWMD's Source Control Permitting Program have resulted in an overall average annual phosphorus reduction of 56 percent – more than twice the 25 percent required by law.
To improve water quality in South Florida's watersheds, ecosystem restoration strategies generally utilize a series of pollution control technologies in a "treatment train" to meet defined water quality goals (as pictured in the animation above). Source controls are the first step in this process, targeting pollutants – specifically, nutrients such as phosphorus and nitrogen – at their source to minimize the amount generated and prevent them from entering waterways.
Source control programs implemented in South Florida by the SFWMD include mandatory Best Management Practices (BMPs). BMPs are practical, cost-effective actions that can be implemented across various land uses – such as agricultural and urban areas – to reduce pollutant levels. Pollutant reductions are accomplished by reducing the volume of water discharged offsite or by reducing the nutrient concentration in the water discharged offsite, or both, depending on the type of BMP implemented. BMP implementation is most effective in reducing nutrients when there is a comprehensive plan made up of BMPs from each type or category below.
Practices that minimize the quantity of off-site discharges that carry nutrients downstream. Examples include:
Discharge structures operate only after a certain level of rainfall is detained onsite.
Water conservation and management practices are employed to retain runoff by optimizing storage in onsite impoundments, soils and ditches.
Practices that avoid excess nutrient application. Examples include:
Employing spill prevention protocols for fertilizer storage and handling.
Applying fertilizer and other soil amendments containing nutrients at the root zone, uniformly, within a controlled boundary and keeping a minimum setback from waterways and no overlapping applications.
Determining specific nutrient requirements through soil testing to apply only what the plant needs.
PARTICULATE MATTER AND SEDIMENT CONTROLS
Practices that reduce movement of nutrients in sediments and particulate matter (plant material). Examples include:
Reducing soil erosion, e.g., maintaining stabilized or vegetated canal banks and swales.
Building and maintaining sumps in canals and ditches to trap sediments.
Removing aquatic vegetation and using barriers at discharge locations to prevent plant particulate matter rich in nutrients from migrating offsite.
Like other pollution control technologies, BMPs have a maximum achievable water quality benefit. In most cases, construction of sub-regional and regional stormwater treatment projects is needed downstream to fully meet the water quality goals for an ecosystem. Successful source control programs limit the excess pollutants that must be captured downstream, decreasing the investment required for stormwater treatment projects and improving their effectiveness.
Point vs. Nonpoint Sources
Source control programs are designed to address two different sources of pollution: point sources and nonpoint sources. Point sources discharge pollutants into a watershed from specific single sources, such as pipes. Nonpoint sources are spread over large areas and are transported into waterways by stormwater runoff.
DEP is responsible for regulating point sources throughout Florida, while SFWMD, FDACS and DEP programs address nonpoint sources in the Southern and Northern Everglades.
SFWMD's successful nonpoint source control programs have seven essential components:
The District's Regulatory Source Control BMP programs include performance criteria and BMP implementation verification to ensure that collective source controls are implemented consistently, pollutant reductions are measured accurately and improvements are implemented if water quality goals are not met. Additionally, the programs include research and demonstration projects to improve the selection, design criteria and implementation of BMPs.
The Southern Everglades Source Control BMP program is one of several strategies to achieve water quality standards in the Everglades Protection Area, which consists of the three Everglades Water Conservation Areas and Everglades National Park. The program includes implementation of phosphorus reduction BMPs and regulatory, voluntary and educational programs as well as integration of state, local and regional water quality projects.
For the EAA and C-139 basins, the Everglades Forever Act mandates a regulatory source control program to implement BMPs to control phosphorus at the source and a monitoring program to assess program effectiveness. It is primarily the source control program's mandated implementation of BMPs in the EAA and C-139 basins that regulates total phosphorus loads in stormwater runoff from these basins prior to inflow to constructed wetlands known as Stormwater Treatment Areas. more »
The District's regulatory source control BMP program for the EAA and C-139 basins is implemented through the Works of the District permitting program in Chapter 40E-63, F.A.C. The program requires permits that include BMP plan implementation in both the EAA and C-139 basins and water quality discharge monitoring plans by permittees in the EAA.
In order to be in compliance, the EAA Basin is required to achieve a 25 percent reduction of the total phosphorus loads discharged in stormwater runoff when compared to the pre-BMP baseline period, and the C-139 Basin must meet phosphorus levels relative to the baseline period – as defined in the Everglades Forever Act – by using specific methods defined within Chapter 40E-63, F.A.C. The specific procedures for determining EAA and C-139 basin compliance, basin-level data collection efforts and farm-level discharge monitoring plans are outlined in Appendix 4-2 of the South Florida Environmental Report.
The District collects water quality monitoring data from the EAA and C-139 basins at discharge locations to evaluate the overall effectiveness of the BMPs in achieving and maintaining compliance with the total phosphorus load reduction requirements. The District also performs site visits to verify BMP implementation and compliance with permit conditions.
Research and demonstration projects are required by statute in the EAA and C-139 basins to investigate and improve BMP effectiveness and design. These projects are conducted by the District in cooperation with the University of Florida's Institute of Food and Agricultural Sciences (IFAS) and basin landowners. Investigation to improve the selection, design criteria and implementation of BMPs is ongoing.
More information regarding the current status of Southern Everglades Source Control programs, including performance measurement results and the status of research and demonstration projects, may be found in Chapter 4 of the South Florida Environmental Report.
The District, DEP and FDACS are directed by the NEEPP to implement a source control program designed to be a multifaceted approach to reducing pollutant loads to the Lake Okeechobee, Caloosahatchee River and St. Lucie River watersheds. The nutrients of concern are phosphorus in the Lake Okeechobee Watershed and both phosphorus and nitrogen in the river watersheds. The source control program includes a water quality monitoring component to assess success in achieving performance goals. more »
The District's regulatory source control BMP program for the Lake Okeechobee watershed is implemented through the Works of the District permitting program in Chapters 40E-61 and 40E-63, F.A.C. It requires users of the Works of the District in the Lake Okeechobee Watershed to reduce phosphorus at the source in order to minimize transport in runoff so that water quality-based limits are met.
The current performance evaluation method within Chapter 40E-61, F.A.C., is based on numerical limitations for parcels developed from the 1989 Surface Water Improvement and Management Plan. Therefore, the evaluation method is currently being revised. Consistent evaluation methods will also be developed for the river and estuary watersheds. Detailed analysis of historical data available for all Northern Everglades basins resulted in development of Draft Technical Support Documents that will assist in tracking source control progress and will be the basis for future rule development.
The NEEPP mandates that the regulatory source control program adopted under Chapter 40E-61, F.A.C., be expanded to encompass phosphorous and nitrogen in the Caloosahatchee River and St. Lucie River watersheds. In addition, the boundary of the Lake Okeechobee Watershed must be modified for inclusion of the Upper Kissimmee and Lake Istokpoga sub-watersheds. More information regarding current rule development may be found on the District's Rules, Statutes and Criteria website.