SCH Number 2025070966

Project Info

Title

Aquifer Storage and Recovery Program

Description

Stockton East Water District (District) proposes to utilize existing supply Well 74-01 for an aquifer storage and recovery (ASR) program on the premises of the Dr. Joe Waidhofer Drinking Water Treatment Plant (WTP). Recharge to the aquifer will utilize drinking water from the WTP at an estimated rate of 450 gallons per minute (gpm). The drinking water is derived from the District’s diversion of water from the Calaveras River and the Stanislaus River. The recovery of the stored water (production) will occur at rates up to 1,500 gpm. The production volume will be limited to between 70% and 80% of the recharge volume. The stored water will serve as a dry-year supplemental supply to the WTP and will also serve to restore groundwater storage in the aquifer during wet years. The discharge of stored water from Well 74-01 will be conveyed to the South Raw Water Reservoir via an existing pipeline. Water in the reservoir will be treated to drinking water standards prior to delivery to the Urban Contractors distribution systems. Two 4-inch-diameter observation wells (OW) will be installed within 100 feet of Well 74-01, including a 200-foot shallow well and a 500-foot deep well, to monitor changes in groundwater levels (WLs) and changes in deep water quality during ASR operations. A second deep OW will be installed approximately 3500 feet northeast of Well 74-01, along an on-site access road, to monitor WL changes.

2 documents in project