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Unified Sewer Plan Update
The Unified Sewer Plan will reflect Pierce County’s ongoing commitment to a healthy Puget Sound and our goals for supporting vibrant communities, effective government, and economic growth.
Pierce County Planning and Public Works is currently updating the Unified Sewer Plan, which is a comprehensive plan that will guide the Pierce County Sewer Division for the next 20 years. The plan describes the sewer service area, existing collection and treatment system and outlines policies, goals and approached that will guide future expansion and improvements.
The Unified Sewer Plan will also address elements required by the Department of Ecology, including the general sewerage planning, expansion of sustainability, resource recovery efforts (biosolids and biogas management), and improved treatment to reduce nutrients in outflow.
Sewer Division staff will engage with ratepayers, elected officials, tribal partners, stakeholders, and regulators to understand their expectations and to develop strategies for how best to balance those expectations while maintaining affordable rates.
Our business case evaluations will include consideration of the environment and social awareness to the standard cost/benefit/risk analysis, and address sustainability, sewer capacity, resource recovery and wastewater treatment byproducts (such as biosolids, biogas and nutrient reduction).
• Support growth and economic development in Pierce County.
• Meet customer expectations of balancing investment value with the health of Puget Sound.
• Facilitate ongoing compliance with current and future regulatory requirements.
• Address regulatory changes that have been made since the last update in 2010 and will explore improvements to existing sewer, water and energy services.
Policy topics for future consideration include:
• How we finance future growth
• Anticipated changes to regulations
• Sustainability and environmental stewardship
• Opportunities for partnerships/regionalization of services such as Biosolids Management
• Evaluation of other services, such as water and energy
Washington State Department of Ecology and the Pierce County Council have approval oversight of the final plan. See below for more detail about the timing and goals for each phase.
(Note: Timelines have shifted due to the pandemic response needs, prioritized policy work, and to ensure coordination with broader Pierce County’s Comprehensive Plan timing.)
The prework and contracting took place in 2019-2020.
Phase 1: Establish Baseline and Boundary Conditions (2020-2023)
Develop guiding criteria for the USP, based on long-term needs of the County. They include:
- Identify stakeholder expectations.
- Develop external drivers’ summary (forecasted regulatory requirements and flows/loading based on population/employment data).
- Define existing financial/organizational capacity.
Phase 2: Develop and Assess Program Options (2023 – 2024)
Identify policy and program options and select preferred alternatives, including:
- Environmental review.
- Business case evaluations.
- Testing of technical approaches with stakeholders.
Phase 3: Develop Implementation Framework (2025)
- Document selected projects, prioritization, and finance strategy.
- Synthesis of the planning document.
- Stakeholder engagement.
Adoption (2025)
Established to dovetail Comprehensive Plan adoption which is required to be completed by Dec. 31, 2024.