DETERMINATION OF NONSIGNIFICANCE Description of proposal: Water system plan update #25-1025 for the Washington Water Services Coordinated Water System that provides drinking water to 220 water systems located in Clallam, Jefferson, King, Kitsap, Mason, Pierce, San Juan, and Thurston counties. The coordinated water systems serve approximately 40,143 connections made up of single family, multi-family commercial and governmental classifications. This non-project action was developed to meet the requirements of Chapter 246-290 WAC & provide comprehensive planning to meet the future water supply requirements for the area served by the applicant. Long-term projects include eventual consolidation of the water systems. Plan implementation may result in future project actions, which will undergo individual SEPA review as appropriate. Proponent: Washington Water Service Company – Coordinated Water System Plan Location of proposal, including street address, if any: The proposal applies to all water systems owned, operated, and managed by Washington Water Service Company located in Western Washington, west of the Cascade Mountains. These systems span a broad geographic area extending from Orcas Island in the north to Grand Mound in the south. Because the proposal involves a companywide Water System Plan update rather than a single construction site, it encompasses multiple service areas and parcels within this regional boundary. Lead agency: Office of Drinking Water, Environmental Public Health Division, Washington State Department of Health. The lead agency for this proposal has determined it does not have a probable significant adverse impact on the environment. An environmental impact statement (EIS) is not required under RCW 43.21C.030(2)(c). This decision was made after review of a completed environmental checklist and other information on file with the lead agency. This information is available to the public on request. This DNS is issued under WAC 197-11-340(2). The lead agency will not act on this proposal for 14 days from issuance. Comments must be submitted by 02-25-2026 to ben.majors@doh.wa.gov Responsible Official: Holly R. Myers, Director, Office of Drinking Water PO Box 47822, Olympia, WA 98504-7822 564-200-2493 /s/Holly R. Myers Dated: 02/11/2026 You may appeal this determination to the Department of Health, Office of Drinking Water no later than 03-13-2026. You should be prepared to make specific, factual objections. Contact Ben Majors, 564-669-0855, to read or ask about the procedures for SEPA appeals. IPL0312011 Feb 11 2026