Kennewick ASR Program Development and Permitting

The City is using ASR to meet growing water system storage and demand needs, optimize the use of existing water rights, and reduce summer withdrawals from the Columbia River. The ASR system stores treated drinking water from the City’s municipal water system in a deep basalt aquifer during the winter and spring months and recovers that water for beneficial use during the summer and fall. GSI helped to complete the feasibility study, conducted pilot testing of the ASR facility, and helped the City successfully obtain a reservoir permit—the fourth permit for underground storage in the state of Washington and one of the highest recovery percentages (92 percent).

Pilot testing of the facility evaluated the (1) feasibility of long-term ASR recharge and storage operations, (2) potential for storing and recovering cool water in a warm-water aquifer (native groundwater temperature is more than 80°F), (3) capacity of the basalt storage zone, and (4) quality of water recovered from storage. Pilot testing has shown positive results and ASR has been beneficial to the City’s management of its water resources: no hydraulic or thermal limitations to ASR operations have been identified, there has been no evidence of aquifer clogging or well performance concerns, and water recovered from storage has met all established drinking water quality criteria. The City has stored and recovered up to 240 million gallons annually and is targeting storage of up to 475 million gallons. The ASR program has been a valuable benefit to both instream and out-of-stream water uses, allowing the City to use the stored water to meet increases in summer demand rather than increasing summer withdrawals from the river.

As of March 2020, the City’s ASR facility is now fully permitted. GSI helped negotiate terms and conditions of the permit with the Washington State Department of Ecology, and the City received one of the highest recovery percentages for permitted systems in the state. GSI continues assisting the City in evaluating the performance of the system and preparing operations, monitoring, annual reporting, and contingency plans as conditioned by the permit.

GSI’s work has involved:

• Designing and implementing ASR pilot testing activities, including operations and maintenance
• Preparing an environmental assessment and analysis (EAA) report
• Developing operations, monitoring, and quality assurance project plans
• Monitoring aquifer and ASR well performance during recharge and recovery operations
• Assessing stored and recovered water quality
• Providing reservoir permitting support
• Preparing annual ASR operations and monitoring reports