Why is stormwater a problem? To give some perspective, the U.S. Environmental Protection Agency indicates that over 40% of waters assessed by the states are too polluted for fishing or swimming. The top four impairments are pathogens, metals, nutrients, and sediment.
Nonpoint sources associated with stormwater account for over 40% of these polluted waters. Conversely, traditional point sources (i.e., wastewater treatment plants) account for only about 10% of these polluted or “impaired” waters. Hundreds of impaired water segments in Florida have lost their “designated use” due, in part, to stormwater pollution.
Florida’s regulatory approach recognizes that stormwater is a nonpoint source and therefore many end-of-pipe technologies are not effective. Rather, a best management practice (BMP) based approach has been embraced using “presumptive criteria,” as codified in the statewide Environmental Resource Permitting (ERP) rule, Chapter 62-330, F.A.C. These BMPs include a menu of site-specific practices that generally involve retention or detention of stormwater runoff. The stormwater treatment target is removal of 80% of the annual average load of post development pollutants for Class III waters and 95% removal for Outstanding Florida Waters.
These minimum targets are codified in Chapter 62-40.432(2)(a), Florida Administrative Code. Further, section 373.4131(3)(b), F.S., authorizes the presumptive BMP based approach.
Emma Rivers Baird, P.E., is a civil engineer with private sector experience in designing and drafting various water conveyance and waste water treatment projects and manual writing. As the DEP State Stormwater Engineer, Emma provides engineering support to the districts for numerous stormwater projects. She is also coordinating the writing and implementation of the changes to Rule 62-330 which is charged with minimizing the impact of known sources of nutrient pollution and strengthening regulatory requirements, under the Clean Waterways Act, Chapter 2020-150, Laws of Florida.
The Florida Department of Environmental Protection is the state’s lead agency for environmental management and stewardship – protecting our air, water and land. The vision of the Florida Department of Environmental Protection is to create strong community partnerships, safeguard Florida’s natural resources and enhance its ecosystems.