The Marysville Sewage Lagoon is a vital water resource infrastructure located in Marysville, Washington. Owned by the local government, this facility is regulated by the Washington Department of Ecology and undergoes regular inspections and enforcement to ensure its proper functioning. The lagoon, completed in 1959, serves as an offstream reservoir for the Tr-Ebey Slough, with a storage capacity of 144 acre-feet and a surface area of 90 acres.

Constructed as an earth dam with a stone core and soil foundation, the Marysville Sewage Lagoon stands at a hydraulic height of 11 feet and a structural height of 4 feet. Despite its low hazard potential, the facility has not been rated for its condition assessment, and the last inspection was conducted in September 2001. With a history of safe operation and minimal risk, this lagoon plays a crucial role in managing wastewater and protecting water quality in the Snohomish County region.

Located in Congressional District 02, Washington, and overseen by Representative Rick Larsen, the Marysville Sewage Lagoon exemplifies the importance of sustainable water management practices in the face of climate change. With a commitment to environmental stewardship and regulatory compliance, this facility serves as a key player in safeguarding water resources and promoting resilience in the face of evolving hydrological challenges.