Olympic Water and Sewer, Inc. (OWSI) is implementing a surcharge for Wastewater Treatment Plant (WWTP) Phase 1 improvements to restore the plant’s hydraulic capacity. The surcharge will become effective on February 24, 2026.
To achieve the required volatile solids reduction necessary for continued authorization of Class ‘B’ biosolids land application, OWSI implemented a process control change that repurposed two of the plant’s original treatment tanks as aerobic digesters. Following this modification, the Washington State Department of Ecology’s 2013 WWTP permit update established a temporary operating limit of half of the plant’s engineered hydraulic capacity until a long-term process solution could be developed. While this adjustment allowed the facility to remain fully compliant, it constrained the treatment train and reduced operational flexibility. As the community grows and climate-driven flow variability increases, restoring this lost capacity is essential to ensuring long-term system reliability.
The WWTP Phase 1 Improvements Project will construct a new, dedicated aerobic digester system—including new tanks, aeration equipment, piping, and modern controls—so that the two repurposed tanks can return to their intended treatment function. Restoring full hydraulic capacity will strengthen the resiliency of the wastewater system, support OWSI’s renewed 20-year biosolids management agreement with Rayonier’s forestry program, and prepare the facility for future capital improvements. This long-planned project is a critical investment that will ensure the WWTP continues serving the community sustainably while enabling future advanced treatment technologies that help protect Puget Sound for generations to come.
This surcharge is required to meet Department of Ecology requirements for our WWTP. Funds generated by the surcharge will cover 70% of the project cost. The estimated total project cost is $3,500,000. When amortized over 20 years at an estimated interest rate of 6%, the total repayment amount is $6,090,497, of which 70% is $4,263,348. The surcharge for each customer or connection is $11.25 per month, billed bi-monthly at $22.50 per billing cycle. The surcharge is scheduled to expire in April 2047, or upon recovery of $4,263,348, whichever comes first. Cost estimates include construction, state excise tax, and federal income tax.
These figures represent the best current estimate of project costs and financing. Upon completion of the project, the surcharge will be adjusted up or down based on actual final costs.
This surcharge will first appear on your April 27, 2026 Water and Sewer billing.
If you have questions about the surcharge or how it may affect you, please contact Olympic Water and Sewer, Inc. at 360-437-8247 to leave a message or email owsi@portludlowassociates.com.
