On January third, a federal court in Virginia ruled that the U.S. Environmental Protection Agency (EPA) is not authorized under the Clean Water Act (CWA) to impose a flow-based total maximum daily load (TMDL) for Accotink Creek in Fairfax, VA.
This TMDL used stormwater flow rate as a surrogate for sediment loading to the stream. The court decided the case in favor of the plaintiffs, Fairfax County and the Virginia Department of Transportation, who sued EPA on the basis that stormwater runoff is not, itself, a “pollutant” as defined by Congress in the CWA. The court found “Congress’s intent to be clear and unambiguously expressed by the language” of the CWA, stating that “EPA’s authority does not extend to establishing TMDLs for nonpollutants as surrogates for pollutants.” You can read the CWA definition of a pollutant here and the full court decision here.
How will this impact municipal, industrial, and construction stormwater permits and implementation? What about local authority over stormwater? Or already finalized TMDLs? The regulated community is secretly (or not so secretly) hoping that this case will have an impact on stormwater permit conditions, reducing the financial burden of the program through EPA’s generally weakened authority over stormwater.
Not being lawyers, we can’t predict the nuances that may ripple through the legal environment, but upon reviewing the court opinion and talking to regulators, we don’t think the impact on permitees will be dramatic. In our opinion, the scope of this ruling has a fairly narrow focus, impacting EPA’s authority over TMDLs that use “nonpollutants as surrogates for pollutants.” For example, this ruling will likely impact pending flow-based TMDLs in Missouri and Vermont. There is also the potential to impact impervious cover TMDLs. It may also impact the status of EPA’s November 2010 memo on stormwater TMDLs, which recommends using flow as a surrogate for other pollutants or impairments.