Sewer Regulator Modification

Sewer Regulator R4 & R39 Modification


This project will improve the efficiency of the trunk sewer conveyance system and reduce or eliminate combined sewer overflows into the Snohomish River. Regulators are flow-control structures that direct normal or modest wet weather flows to the wastewater treatment plant and divert excessively large wet weather flows to the Snohomish River. The Washington State Department of Ecology limits overflows to the river to not more than one event per year.

Project Updates

Check back for regular updates regarding upcoming construction activities, traffic and parking restrictions and schedules.  

Project Location 

Project Map (PDF)

R4 site—located at the intersection of Chestnut Street and the alley north of Everett Avenue. Construction activities will occur in the street and within the landscaped area to the south. Modifications will be made to several manholes and flow control structures as well as associated pipe connections. The size and depth of the sewer pipes and manholes at this location will necessitate use of large excavation equipment, haul trucks etc. It may be necessary to remove a panel from the existing concrete sound barrier wall and to utilize a portion of the roadway shoulder of the NB I-5 offramp approaching Everett Avenue. In addition, some portions of the watermain will need to be replaced and relocated. Upon completion, the street and landscaped area will be restored.

R39 site—located in the middle of the intersection at Summit Avenue and 26th Street. Construction activities will occur in the middle of the street. Modifications to the existing manhole will be comparatively less involved than at the R4 site. Finished pavement restoration will be done as part of the Cleveland Ave Sewer and Stormwater Project.


Construction: August through December 2017

It is estimated that R39 will be completed within 1 or 2 months and R4 by the end of December.

Related Documents

SEPA17-008 Determination of Nonsignificance (PDF)


Dave Voigt, P.E., Project Manager, 425-257-8983 or email

Tom Fuchs, Construction Manager, 425-257-8931 or email