Water Quality

Under the Clean Water Act, wastewater facilities are required to treat wastewater with secondary treatment, which usually involves biological processes. In November of 2003 however, U.S. EPA proposed a bypass of some wastewater from secondary treatment during periods of peak wet weather flow. The proposal is known as the "blending" policy, because before the bypass flow is discharged, it is combined with effluent that has gone through secondary treatment. This practice is allowed as long as the discharge still meets effluent limitations or any other limitation related to water quality standards.

EPA's proposed policy clearly defines the situations in which blending would be allowed and includes specific guidance on how the policy should be implemented. But the proposal was just the first step. It was followed by a public comment period, during which all interested parties could submit their views on the proposal to EPA. Using a workgroup process, NEIWPCC developed and submitted a comment letter that expresses the views and opinions of our member states.

Broadly speaking, our states support the policy. They recognize that in some situations blending is necessary and already occurs somewhat regularly. The policy would improve matters by providing a national guidance and framework for implementation of the practice. It would help eliminate inconsistencies among regions and improper application.

The policy also helps states in one other important respect: Right now, limited infrastructure financing and tight budgets make treatment plant operation a real challenge for many states. The blending policy would allow budget-strapped states to get the most out of existing, aging wastewater facilities until the day when funds are available to acquire new technology and upgrade facilities.

Our member states did express the need for flexibility in some situations, and they feel blending should not be done when the discharge goes directly to a water body that is already impaired and requires a TMDL. Still, NEIWPCC and our states are in favor of the proposal, because it sets a national standard and clears up inconsistencies. NEIWPCC submitted its comment letter in February 2004.

To date, EPA is still reviewing and considering comment letters related to the proposal. So far, there is no indication from the agency as to whether it will proceed with finalizing the blending policy. Download a copy of NEIWPCC’s comment letter.