Skip to main content
King County logo

The Conveyance System Improvement (CSI) Program looks at ways to improve the conveyance system and address public health concerns, while ensuring that the system has sufficient capacity to respond to regional growth.

King County’s regional conveyance facilities are located throughout the County’s wastewater service area and include over 390 miles of regional conveyance pipes, 47 pump stations, and 25 regulator stations.

Since 1999 the CSI Program has focused on guiding major upgrades and improvements to King County-owned regional wastewater facilities.

Now posted: 2017 CSI Program Update , (2 MB)

Summary: The CSI Program Update culminates in a prioritized list of projects to improve capacity in the separated portion of the regional wastewater treatment system. The prioritized list provides WTD direction on near term projects for implementation and long term program cost projections for financial planning. 

The CSI Program Update report presents the prioritized list of conveyance system projects. The report also contains a summary of the entire process that led to the prioritized list of projects. The report is available at the link above. 

Consistent with other CSI Program Update activities, the prioritized list of projects was shared with the MWPAAC Engineering and Planning Subcommittee and the local agencies that contract with WTD for wastewater treatment services for input.

The locations of these prioritized projects are displayed below.


Learn more about the 2017 CSI Program Update.

Conveyance System Improvement

For more information, please contact:

Steve Tolzman

Steve Tolzman
Capital Project Manager