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EPA - Clean Water Act Can Be Used to Regulate Air Emissions


In a November 15 memorandum, EPA opened the door for states, and EPA, to regulate greenhouse gas (GHG) emissions under the Clean Water Act (CWA), air being a tributary of water.  The memorandum issued by the Office of Wetlands, Oceans and Watersheds "recognizes that the [section] 303(d) program under the CWA has potential to complement and aid" other efforts to control GHG emissions. 

The memorandum directs that states should designate waters not meeting water quality standards because of acidification.  Section 303(d), 33 U.S.C. 1313(d), provides that when a state identifies waters not meeting quality standards (called impaired waters) the state shall also establish a total maximum daily load (TMDL) for the pollutants impairing the water quality.  A TMDL is a cap on the discharges (here emissions) and the state can allocate that cap among dischargers, giving each a specified limit.  If EPA disapproves a state's TMDL, EPA is empowered by section 303(d) to issue its own TMDL.  States designating multiple impaired waters can establish a priority ranking to set the order in which the state proposes to establish TDMLs to control pollutant loads.  In other words, using the CWA's TMDL provisions, states (generally through their water quality agencies that are empowered to issue water discharge permits) or EPA can tell electric utilities, manufacturers, etc. how many pounds/tons of CO2 they can emit without violating the CWA.  Persons who already have CWA discharge permits may find their permits need to be amended and persons who are discharging regulated substances (here GHGs that cause ocean acidification) may be required to get CWA permits, now subject to a TMDL cap.

The November 15 Memorandum states: "Ocean acidification, like climate change, is primarily caused by increasing carbon dioxide (CO2) concentrations in the atmosphere.  As a result of absorbing large quantities of human-made CO2 emissions, ocean chemistry is changing, which is likely to negatively affect important marine ecosystems and species…."

EPA's memorandum was issued as part of a settlement in a lawsuit brought by the Center for Biological Diversity (CBD) challenging Washington State's list of impaired waters.  CBD argued that Washington had failed to designate waters impaired by acidification.  CBD's press release, issued on the heels of the EPA memorandum, states: "We need prompt action to curb CO2 pollution and the Clean Water Act can help."  CBD's lawsuit is a part of a continuing $17 million national legal campaign to regulate GHG emissions using the CWA and the Endangered Species Act (actions that kill or injure listed species because of habitat change are prohibited).  In early 2007, for example, CBD filed petitions in California and several other states demanding that the states regulate GHGs under the CWA to prevent ocean acidification.  The petition CBD filed with California, for example, stated its purpose was to force California to develop a water pollution standard for GHGs and to then set limits on GHG emissions in the state.  EPA's November 15 action effectively adopts CBD's position, nationalizing it under an EPA standard.

CBD's lawsuit was the first of its kind challenging EPA's failure to use the CWA to regulate ocean acidification.  The lawsuit and the resulting EPA November 15 memorandum mark the beginning of a new regulatory era for GHG emissions.  Through this and related actions, CBD is telling everyone that it may not matter whether Congress passes cap and trade or other legislation to regulate GHG emissions because existing statutes like the CWA and the Endangered Species Act are sufficient to regulate these emissions.

A partner with Nossaman, George Mannina, Jr. has more than three decades of experience with environmental litigation and government relations.  He can be reached at 202.887.1491 or

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