Wastewater Treatment
Lynnwood Wastewater treatment plant (WWTP) collects and treats wastewater from a sewer service area of approximately 6,000 acres. The City’s goal is to protect public health and the environment by effectively treating sewage before it is discharged back into natural water bodies.
WWTP Plant Processes
Lynnwood WWTP employs a series of techniques and technologies to fulfill our mission of protecting public health and preserving the environment. Discover how we remove impurities, harness new technologies and achieve compliance with rigorous environmental standards.
Lynnwood wastewater treatment plant upgrades project
The City of Lynnwood is investing in major upgrades to the Lynnwood Wastewater Treatment Plant to protect public health and the environment by effectively treating sewage before it returns to Puget Sound. The treatment plant was built over 60 years ago, and over the years, Lynnwood has upgraded the facility to modernize and accommodate growth. Due to the facility’s age, it needs more updates.
Benefits of this necessary project include:
- Improved odor control around the facility
- Improved water quality, providing healthier habitat for salmon and wildlife
- Reclaiming valuable resources from wastewater to reuse
- Increased reliability to serve the growing populations of Lynnwood and Edmonds
Schedule
Design is expected to begin in late 2026.
Early Planning (2020 - 2025)
In 2020, the City began a thorough process of evaluating the treatment plan and sewer system. The City found the treatment plant needs major updates to meet changing environmental regulations and accommodate growth. Over the past five years, the City has been responsibly developing a funding plan for this necessary project. When the project team has a better understanding of this project’s schedule and cost, the City will share more information at local events, meetings, on our website and through mailings.
Public Engagement
The City of Lynnwood is committed to sharing information and engaging the community throughout design and construction. In 2026, you’ll see the project team out at community events and project information included in City of Lynnwood newsletters.
Project Library
2025
Public Works Director Statement Regarding City’s Eminent Domain Process(PDF, 144KB)
Project Fact Sheet(PDF, 324KB)
2024
Lynnwood WWTP Facility Plan(PDF, 48MB)
Value Engineering Review of the Lynnwood WWTP Facility Plan Technical Memorandum(PDF, 48MB)
Sign up for Wastewater Treatment Plant notifications
Questions? Contact Ehsan Shirkhani, Public Works Program Manager, 425-670-5218 or pwrequest@LynnwoodWA.gov