Stormwater regulation

The Conservancy of Southwest Florida advocates for better stormwater management, treatment and regulations to protect our region’s water resources from stormwater runoff. 

Why It Matters

Stormwater picks up debris, chemicals, insecticides, fertilizers, dirt, pet waste, and other pollutants that flow into a storm sewer system or directly to rivers, wetlands or coastal water. Any water which enters a storm sewer system without first being treated by a Best Management Practice (BMP), such as a detention or retention pond, a swale or raingarden, or some other BMP is untreated stormwater runoff which is then discharged directly into waters we use for swimming, fishing, and drinking – carrying the pollutants with it.

Moreover, there are times when the BMPs are not sufficient to treat the water – either through a design flaw, changing precipitation patterns, or increased pollutant loading.

Polluted stormwater entering into drinking water sources affects human health and taxpayers pocketbooks by increasing water treatment costs when that water needs to be used for potable water supplies.  Polluted stormwater can also carry bacteria to beaches or other swimming areas, which can result in human health impacts and beach closures.

Stormwater also transports excess nutrients like nitrogen or phosphorus from lawns, agricultural areas, and golf courses which can stimulate harmful algal blooms (HABs).  HABs often cause a chain reaction resulting in the lowering of dissolved oxygen levels, loss of sea grasses, fish kills, and the degradation of water quality.

Some HABs are toxic to humans as well.  Freshwater cyanobacteria (blue-green algae) can produce toxins which can affect the liver, skin or nervous system. Red tide blooms occur in the Gulf of Mexico and can be exacerbated by nutrient-laden stormwater runoff.  Red tide can cause respiratory issues for some beachgoers and has been linked to fish kills and manatee deaths.

The Conservancy of Southwest Florida advocates for better stormwater management, treatment and regulations to protect our region’s water resources from stormwater runoff.  The Conservancy engages on this issue at both the local and state level.

Locally, the Conservancy advocates that existing and new developments have sufficient stormwater treatment in place and do not exacerbate any current water quality problems, or create new ones.  At the state level, the Conservancy has been involved in the development of updated statewide stormwater rules which now need to be adopted and implemented.


The Conservancy works to ensure the Total Maximum Daily Loads (TMDLs) are sufficiently stringent and that the Basin Management Action Plans (BMAPs) are updated regularly with the most recent data and information for restoring the waterbody back to a healthy state. 

Total Maximum Daily Loads (TMDLs)


Southwest Florida waterbodies suffer from a number of pollution problems, including nutrients from excess fertilizer and stormwater runoff, bacteria, and metals such as copper, iron and mercury. If a waterbody is polluted due to anthropogenic (i.e., human related) activities, the Florida Department of Environmental Protection (DEP) is required to set a pollutant limit – known as a Total Maximum Daily Load (TMDL). 

A TMDL is essentially the maximum load (amount) of any given pollutant that is allowed in a waterbody. Once a waterbody receives a TMDL, certain types of facilities, like wastewater treatment plants, are automatically required to make sure their discharges are in compliance with the TMDL.  These types of dischargers are referred to as “point sources” because the source and location of the discharge is readily identified. 

There is another type of pollution, “nonpoint source” pollution, which is harder to pinpoint the source of, and often has many different contributors – such as residential areas, golf courses, urban stormwater, or agricultural fields. That’s where Basin Management Action Plan’s (BMAPs) come in.

Basin Management Action Plans (BMAPs)


BMAPs are multi-year implementation plans designed to achieve the limits set by the TMDL within a 20-year timeframe. 

The DEP, in coordination with other agencies, local governments and stakeholders, allocates specific reductions to each contributing polluter – whether it’s a city, county, or other municipality, as well as allocations for nonpoint sources, like agriculture, which are asked to implement Best Management Practices (BMPs) to reduce their contribution to the impairment. 

Unfortunately, BMPs have not proven to be effective enough at controlling nonpoint source pollution, and there is little enforcement by DEP or other agencies at this time. This is one of many challenges for restoration plans like BMAPs – ensuring that the estimated reductions in the plan are actually achieved in the real world implementation.

The Conservancy actively advocates for solutions, such as requiring monitoring of BMPs for effectiveness and enforcement when a BMP is not effective.

There are many TMDLs, and several BMAPs within the Conservancy’s 5-county region, some of which include:

  • The Gordon River (TMDL)
  • Lake Trafford (TMDL)
  • Cocohatchee River (TMDL)
  • The Imperial River (TMDL and BMAP)
  • Hendry Creek (TMDL and BMAP)
  • Caloosahatchee River and Estuary (TMDL and BMAP) 

The Conservancy is involved at all levels of local TMDL and BMAP development, from the time the waterbody is designated impaired, through the various phases of the BMAP. 

The Conservancy works to ensure the TMDLs are sufficiently stringent and that the BMAPs are updated regularly with the most recent data and information for restoring the waterbody back to a healthy state. 

The Conservancy advocates for appropriate and timely BMAP clean-up projects and enforcement of required pollution reductions if targets are not being met.  

interested in learning more? dive deep into the documents and resources on this topic and others by heading to the Policy Resource Center!