Wastewater Treatment Program

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 Wasetwater Treatment Plant Processes(PDF, 17MB)
• Procesos de la Planta de Tratamiento de Aguas Residuales de Lynnwood(PDF, 20MB)

In 2020, the City began a comprehensive evaluation of the existing wastewater treatment plant and sewer system to better understand current conditions, aging infrastructure, capacity needs, and future regulatory requirements. This effort resulted in the development of a Facility Plan that established a long-term roadmap for improvements to the wastewater treatment facility and supporting sewer infrastructure. The plan identified key Capital Improvement Projects (CIP) needed to maintain reliable service, improve system resiliency, address aging assets, and ensure compliance with evolving environmental regulations for decades to come.

The 2024 Facility Plan document and Value Engineering Report are available here:

2024 Facility Plan(PDF, 48MB)

Value Engineering Report(PDF, 5MB)

The Lynnwood Wastewater Treatment Plant Upgrades Project is a long-term, phased initiative planned through approximately 2034 to modernize aging infrastructure and prepare the facility for future community and environmental needs. The project is currently in the Basis of Design (BOD) phase, where the team is refining key design decisions and confirming the recommended approach before advancing into detailed design, permitting, and phased construction.