The Vortab Co. shared details of its Elbow Flow Conditioner. The Vortab...
The Bush administration is issuing a change in policy that would allow cities and towns to skip a required treatment procedure for sewage they pump into rivers, lakes and coastal waters during high rains.
Should local governments have to spend billions of tax dollars upgrading plants so peak flows of sewage can receive all the treatment required under normal conditions? That is the question that this policy change aims to settle.
The administration's plan would allow hundreds of communities escape that expense by only partially treating sewage surges in big storms. Environmental groups and some federal regulators say those flows should be treated completely to keep disease-carrying microbes out of recreational waters.
The Environmental Protection Agency plans to propose the policy change this week, and there will be 60 days for public comment before it can be finalized.
"We've been pushing hard for a national policy on this," said Ken Kirk of the Association of Metropolitan Sewerage Agencies, which represents public treatment plants. Kirk stated that there has beenconfusion over required treatment in wet weather conditions and said that it would be very costly for many communities if their treatment plants must be upgraded.
Heavy wastewater flows that come in wet weather often exceed the capacity of plants' biological treatment. Many plants divert peak flows around the second treatment step, blending diverted waste with fully treated sewage before it is released.
The EPA's new policy would permit blending and say that blended waste still must meet normal discharge standards, including limits on bacterial content and clarity.
But "those standards don't cover viruses or parasites ... and those are the contaminants that don't get removed if you skip biological treatment," says Nancy Stoner of the Natural Resources Defense Council. Blending "will put more of those contaminants in water supplies."