Skyway I/I reduction project

What you can expect during construction

Construction began in mid-April 2011 and is expected to be completed in March 2012. Residents should disconnect improper connections prior to start of construction.

Example of excavation pit dug near house


Example of pipe bursting


Replacement process. For more information, view the Preconstruction meeting presentation, March 30, 2011 (1.4 MB, PDF).

Construction will include replacement of approximately 21,400 feet of sewer main in the right-of-way, replacement of 99 manholes and replacement of side sewers on 332 properties. During construction, King County will maintain a 24-hour project hotline and will work closely with the project construction team to address noise, dust and other community concerns. Work hours will be between 7:30 a.m. and 4:00 p.m. Monday through Friday. Residents will be given 48 hour advance notice of side sewer replacement on their property as well as advance notice of any traffic disruptions.

Side sewer replacement process

• Excavation pits are dug at connection with sewer main and near house
• Possible excavation of additional pits if there are multiple bends across the yard
• Side sewer is replaced using pipe bursting technique. Existing pipe is burst apart by a bursting head and new pipe is pulled into place behind the bursting head.
• Yard improvements disturbed by pipe bursting will be repaired, including landscaping and patching of driveways and sidewalks
• Installation of cleanout capped at grade
• Photo log of original improvements required to verify restoration

Sewer main replacement process

• Access pits are dug and covered with steel plates
• After side sewers are replaced sewer main is replaced and laterals reconnected
• New manholes are installed
• Access pits are filled and areas are restored