People seeking information about upcoming construction on a King County pollution-control project in Magnolia are invited to an open house. It will take place Thursday, Jan. 30, from 6 to 8 p.m., at the Elliott Bay Marina in the Seattle Yacht Club Building (2601 W. Marina Place).

King County is building its South Magnolia Combined Sewer Overflow (CSO) Control Project to protect water quality on rainy days, when large volumes of stormwater enter the sanitary sewer system and cause overflows into Puget Sound.

The open house will enable people to meet King County staff and contractors who will build a 1.5-million-gallon underground storage tank on property acquired from the Port of Seattle near Terminal 91 and the Magnolia Bridge on 23rd Avenue West.

The tank will temporarily hold excess stormwater and wastewater during large storms. When storms subside, flows will be sent to West Point Treatment Plant in Discovery Park. A new gravity sewer pipeline will connect existing sewer lines on 32nd Avenue West to the storage facility.

The project set the stage for a 2013 land acquisition deal between the county and the City of Seattle and Port of Seattle that will one day enable expansion of waterfront access at Smith Cove Park, which is a longtime vision of the community.

Stellar J Corp. of Woodland, Wash., was awarded the contract to build the storage facility last fall. Stellar J teams are currently working on other King County Wastewater Treatment Division projects, including upgrades of the Interbay and Kirkland pump stations and the North Beach CSO Control Project.

Bids on the second contract, which entails the sewer pipeline work on 32nd Avenue West, will open on Tuesday, Jan. 28.

For more information, contact Monica Van der Vieren at monica.vandervieren@kingcounty.gov or at (206) 477-5502.