Sewer systems and wastewater treatment in Kitsap County
Be part of the planning process for how Kitsap County will maintain their sewer utility system over the next 20 years.
Who We Are
The Sewer Utility Division operates four wastewater treatment plants and maintains 64 pump stations, 170 miles of gravity pipe, 48 miles of force mains and 3,775 manholes in Kitsap County.
The Kitsap County sewer system has four basins, each with a treatment plant and a corresponding collection system: Central Kitsap, Manchester, Suquamish, and Kingston.
Kitsap County’s Sewer Utility processes over 4 million gallons of wastewater per day from over 12,000 customers.
There are a variety of essential jobs that make this possible, including engineers, mechanics, electricians, operators, inspectors, maintenance workers, and lab analysts, to name a few. Careers in sewer systems and wastewater treatment are vital to our communities.
Our Facilities
The Central Kitsap Treatment Plant (CKTP) began operating in 1979 and receives flows from the Central Kitsap area, Silverdale, Keyport, City of Poulsbo, Naval Submarine Base Bangor, and Naval Undersea Warfare Engineering Station at Keyport.
CKTP provides solids treatment for the Kitsap County's three other wastewater treatment plants (Kingston, Suquamish, and Manchester), and hauled septage and fats, oils, and grease (FOG) treatment from community members in the region who are not connected to the sewer system.
The plant is a biological nutrient removal (BNR) facility with a rated maximum month flow rate capacity of 6.0 MGD.
The Kingston Treatment Plant was constructed in 2005, replacing a wastewater treatment plant originally constructed in 1974. In 2006, the outfall to Appletree Cove was replaced and realigned.
The plant is permitted to treat a maximum month design flow of 0.292 MGD. The plant is an oxidation ditch (extended aeration) type activated sludge facility.
The Manchester Treatment Plant was originally constructed in 1969 and after a series of upgrades was converted to a conventional activated sludge treatment system in 1998 with a plant capacity of 0.46 MGD.
The Suquamish Treatment Plant was constructed as an activated sludge process in 1975 but was reconstructed as a Sequencing Batch Reactor (SBR) system in 1997. A rotary drum thickener (RDT) system, thickened sludge storage tank (TSST), and sludge loadout facility were constructed in 2017.
The plant is designed for a maximum monthly flow rate of 0.4 MGD and a peak flow of 1.0 MGD.
Capital Projects
The Sewer Utility manages capital projects to upgrade outdated infrastructure, most of which is 45+ years of age. Improvements are planned to manage future energy use, meet changes in regulation requirements, and increase sewer system capacity for the County's growing population.
In compliance with RCW 36.70A.130(2)(a)(iv) and KCC 21.08.020, Kitsap County's Sewer Utility conducts an assessment of county owned/operated municipal sanitary sewer systems and develops a Six-Year Capital Facilities Plan .
20-Year Sewer General Plans for Central Kitsap, Kingston, Manchester, and Suquamish as well as maintenance records are used to develop the six-year list of improvement projects.
Public Works construction projects provide safe infrastructure for a growing population. As we plan, we find ways to protect our natural environment to keep Kitsap County a great place to live.
Find projects in your neighborhood at kcowa.us/project .
Sewer General Plans
The Sewer Utility is updating the Sewer General Plans for all Kitsap County service areas. Draft plans are available for public review.
Sewer General Plans are required by WAC 173-240-050 and RCW 90.48.110 to:
- Discuss Treatment Plant operations, regulatory requirements, and operational needs over the planning period 2023-2042.
- Factor regional growth, and policies to support the County Comprehensive Plan.
- Provide preliminary information to drive future capital projects with a potential funding strategy.
The General Plan is reviewed and approved by Department of Ecology and Kitsap County Board of County Commissioners.
Financial Strategy
The Sewer Financial Plan supports all four sewer basins in one document. Figure 12-4 graphically represents a proposed funding strategy to support capital projects through 2042.
WAC 173-240-050 and RCW 90.48.110 requires a funding strategy for Ecology review and plan approval.
The financial strategy is a mix of bonds and pursuance of grants and low-cost loans balanced with overall rate increases of 6.31% in 2025 (already adopted) and 6% per year from 2026 through 2042.
Future increases to sewer rates must be approved by the Kitsap County Board of Commissioners which will require a separate public process.
Your Impact
Be part of the planning process for how Kitsap County will maintain their sewer utility system, and tackle challenges like growth, maintenance, and emerging permit requirements for the next 20 years. The proposed Sewer General Plans for all Kitsap County service areas are available for public review.
The public comment period for SEPA and SERP is open from March 15 until 5:00 pm April 30, 2025.
A public meeting will be held from 5:30 to 7 p.m. on Thursday, April 17, 2025, at the Kitsap County Commissioners Chambers at 619 Division Street in Port Orchard. A Zoom meeting option is available at https://us02web.zoom.us/j/88012206828 . Meeting ID: 880 1220 6828
Comments can also be provided via email at Sewerutilitydivision@kitsap.gov
OR via mail at:
ATTN: Sewer General Plan Kitsap County Public Works Anthony Burgess 614 Division Street. MS - 26 Port Orchard, WA 98366
