Title

Categorical Exclusion For the Georgetown Wet Weather Treatment Station (GWWTS)

Document Number

N2018011

Document Type

CATEX

Project Description

The GWWTS project includes construction of a new wet-weather treatment station (WWTS); conveyance system improvements including approximately 3,000 linear feet of new conveyance pipelines, a new regulator station, and other conveyance system modifications to connect new and existing pipes; and a new outfall structure. The purpose of the project is to reduce the volume and frequency of discharges of untreated combined sewage (sanitary sewage and stormwater) to the Lower Duwamish Waterway. During wet-weather events, flows of combined sewage would be conveyed to the WWTS, where they would be screened, attenuated in an equalization basin, and then treated by ballasted sedimentation and UV disinfection. The flows of treated water would then travel through new conveyance pipelines to a new outfall structure in the Lower Duwamish Waterway.

EPA Region/Headquarters Office

OW

State or Territory

WA

Point of Contact

Alejandro Escobar
202-564-9047
escobar.alejandro@epa.gov

Date of Issuance

2018-02-05 00:00:00.0

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