Physical drainage problems are merely one aspect of the stormwater management challenge faced by Florida's communities. Increasingly complex water quality management and water supply demands add new and rapidly changing dimensions to what has primarily been a relatively straight forward matter of controlling runoff rates and volumes for flood management objectives in past years. Water quality impacts like water pollution in the lakes, streams and estuaries caused primarily by increasing stormwater discharges are less visible problems but are currently becoming important considerations in annual decisions on staffing and capital investments of a community's stormwater management activities.

Water pollution is a significant drainage problem that must be carefully evaluated in Florida communities. Drainage systems create other physical problems, which are not yet widely recognized, such as water pollution in the canals and in receiving waters. Stormwater from urban areas not only carries pollutants directly into the drainage ditches and canals, it also transfers them downstream toward the fragile estuaries, wetlands and streams.

Severe and regionally significant water pollution incidents can occur if hazardous, toxic, or exotic chemicals or materials were spilled or dumped into storm drains, swales, or channels which discharge into a drainage system or canal. A major spill is not required to create a serious water pollution problem. Even runoff from residential properties may carry with it a portion of the pesticides, herbicides and fertilizers applied by homeowners, oil and antifreeze improperly disposed of by home mechanics, as well as paints, paint thinners/solvents and other wastes from home improvement projects.

Construction activities can also be a source of many of the same pollutants. While the flat topography and sandy soils in the central and coastal portions of Florida reduce erosion and sedimentation impacts on stormwater quality compared to the clay soil areas of the panhandle area, there is still a tendency for some pollutants to attach to soil particles and thus increase the impact of land?disturbing activities. Excessive fresh water entering the brackish environment of the Florida's bays, estuaries and tidal river segments is itself a pollutant to that environment, which depends on a proper saline balance to sustain critically important rearing habitats for fish and wildlife.

Equally significant, but frequently overlooked, are the pollutant loads contributed by agricultural and industrial activities. Modern agricultural practices use fertilizers, herbicides and pesticides to improve crop yields. These chemicals can enter stormwater management systems through agricultural runoff and, to a limited extent, through return flows and excessive irrigation. Stormwater can pick up a wide variety of chemicals as it flows across industrial sites as well as solids that cause turbidity and produce sediments, nutrients, oils and greases, and oxygen demanding substances. Stormwater from agricultural and industrial areas in Florida has been shown to have a significant cumulative impact in rivers, estuaries, wetlands and streams.

In addition to these deficiencies, many Florida communities have not specifically incorporated water quality elements into their community's stormwater management program. Few local governments, except those subject to the conditions of a MS4 Permit, have developed stormwater quality programs. Implementation of pollutant load reduction goals through ongoing regulatory and programmatic activities of the FDEP, National Estuary Programs and Water Management Districts will mandate that cities and counties become more involved in eliminating non?point sources of water pollution in future years.

Florida communities that were required to apply for MS4 Permit coverage pursuant to EPA's Phase 1 program has to prepare system mapping, a baseline water quality assessment and discharge monitoring program to characterize the quality of local stormwater discharges, and a description of their present and planned operational and capital improvement programs with its management and funding approach. The result of this effort is that these cities and counties now have a better understanding of ambient water quality conditions, annual non-point pollutant discharges and their sources within the community.

Engineering standards, operational priorities and practices, and regulatory programs have also been influenced as the permitting process progresses. A community may have to accept additional responsibility for cleaning detention and conveyance systems, oil separation systems, first?flush diversion projects, and other management practices.

Erosion and sediment control is another EPA priority for stormwater management. Although not considered a major water resource problem in most Florida communities, EPA requires that construction?related erosion control be addressed through both construction site management practices and discharge permits for larger construction sites. Development in a community is often one of the most visible activities but it is often not being tightly controlled in terms of water quality impacts. This contradiction should be viewed as a clear indication that the community should evaluate the potential water quality benefits of developing new standards for site development and construction that enhance erosion and sediment control practices and minimize/eliminate water quality problems during and after construction.