Clean Water Act and Pollutant Total Maximum Daily Loads (TMDLs) [January 17, 2014] [open pdf - 310KB]
"Section 303(d) of the Clean Water Act (CWA) requires states to identify waters that are impaired by pollution, even after application of pollution controls. For those waters, states must establish a total maximum daily load (TMDL) of pollutants to ensure that water quality standards can be attained. A TMDL is both a quantitative assessment of pollution sources and pollutant reductions needed to restore and protect U.S. waters and a planning process for attaining water quality standards. Implementation of Section 303(d) was dormant until states and the Environmental Protection Agency (EPA) were prodded by lawsuits. […] First, Section 303(d) does not require implementation, and states' strategies for implementation vary widely. Only a few have laws requiring implementation plans, while many others rely on less structured policies. Second, a number of barriers to implementation can be identified. The most prominent is insufficient funding, but technical impediments such as insufficient scientific data also are a challenge. At the same time, factors that may aid effective implementation include active involvement of stakeholders and governments, and adequate resources. The TMDL program is in a period of transition and increasingly is addressing new challenges-- more complex TMDLs, larger scale impairments, and nonpoint sources. Other than oversight hearings on the Chesapeake Bay TMDL, Congress has not shown active interest in the TMDL program for more than a decade. Some stakeholders, especially states, believe that several issues present Congress with an opportunity to examine the TMDL provisions of the CWA."
CRS Report for Congress, R42752