EPA proposes requiring sewage disinfection for Skagway, Wrangell WWTPs

The U.S. EPA is proposing limits on the amount of bacteria and other microorganisms Skagway’s and Wrangell’s wastewater treatment plants (WWTPs) will be allowed to release to Taiya Inlet in Alaska.

This is the second public comment period for the Wrangell WWTP; the draft permit that was released for public comment in October of 2022 has been revised.

Currently, the discharges from the Skagway and Wrangell facilities are not disinfected, contain high levels of fecal coliform and enterococcus bacteria, and rely upon a large “mixing zone” area to meet Alaska’s water quality standards for bacteria.

EPA is proposing draft permits for the Skagway and Wrangell facilities that contains more stringent bacteria limits. ADEC has indicated that these limits will be a condition of its certification of the permit under Section 401 of the Clean Water Act. The proposed limits will require upgrades to the existing plants. The draft permits propose to allow the plants five years to comply with the new limits.

Over the next several months EPA intends to propose new Clean Water Act permits for Ketchikan and Petersburg that would also require their treatment plants to significantly reduce releases of bacteria to local waters within five years.

The draft permits waive the secondary treatment requirements for the Skagway and Wrangell facilities. Most municipal wastewater treatment plants in the U.S. are required to conduct “secondary” treatment, which involves a combination of physical and biological treatment requirements to remove organic load and solids. However, in limited circumstances, Section 301(h) of the Clean Water Act authorizes EPA to issue discharge permits requiring less than secondary treatment to plants that discharge to marine waters.