An excerpt from the report:

“The Florida Legislature, through the Watershed Restoration Act (Section 403.067, Florida Statutes), directed the Florida Department of Environmental Protection (DEP) to provide a report with recommendations on water quality credit trading (referred to as “pollutant trading” in the law). The DEP consulted extensively with a Pollutant Trading Policy Advisory Committee (PTPAC) comprising expertise from regulated interests, environmental organizations, water management districts, and local governments. 

Water quality credit trading is a voluntary, market-based approach to promote protection and restoration of Florida’s rivers, lakes, streams and estuaries and would supplement and enhance the other voluntary, regulatory and financial assistance programs already in place. Trading is based on the fact that businesses and industries, wastewater treatment facilities, urban stormwater systems, and agricultural sites that discharge the same pollutants to a waterbody (basin, watershed or other defined area) may face substantially different costs to control those pollutants. Trading allows pollutant reduction activities to be environmentally valued in the form of “credits” that can then be traded on a local “market” to promote cost-effective water quality improvements. 

The full text of the report can be found here: Water Quality Credit Trading Final Report – December 2006.pdf