Drafter
Clerk 08/21/2026
title
AN ORDINANCE relating to the sale of biomethane held by the county; authorizing the wastewater treatment division to enter into an agreement for the sale of pipeline quality biomethane produced at the South Treatment Plant to Puget Sound Energy.
body
STATEMENT OF FACTS:
1. The wastewater treatment division of the department of natural resources and parks operates three regional wastewater treatment facilities, including the South Treatment Plant in Renton, Washington, which treats approximately twenty-eight billion gallons of wastewater each year.
2. Anaerobic digesters at the treatment plant generate methane biogas as part of the water and associated solid material treatment and purification processes.
3. Since 1988, the wastewater treatment division has been removing impurities from the digester biogas to create what is then called pipeline quality biomethane. The biomethane meets gas quality standards equivalent to fossil fuel-derived natural gas, and as such is a direct substitute for fossil fuel natural gas. The pipeline quality biomethane gas can be injected into the regional natural gas pipeline.
4. Between 1988 and 2016, the pipeline quality biomethane not consumed at the treatment plant was injected into the natural gas pipeline and sold directly by King County to Puget Sound Energy.
5. In addition to the energy content of the pipeline quality biomethane, the origin of the biomethane as a byproduct of the wastewater treatment process provides significant greenhouse gas reduction and other environmental benefits when compared to the consumption of fossil fuel-derived natural gas.
6. Those environmental benefits, as an extension of the energy content, are recognized as environmental attributes. Environmental attributes refer to renewable energy or other characteristics of a resource that are distinguished from a commodity and can have financial value related to both voluntary and mandatory environmental requiremen...
Click here for full text