United Water Conservation District reports progress on siphon, monitoring wells, pipeline and extraction barrier

Chris Coppinger, senior geohydrologist at United Water Conservation District, briefed the Fox Canyon Groundwater Management Agency board on March 26 on progress of four sustainability projects partially funded through an DWR Sigma Implementation Grant that was routed through FCGMA to United.

The projects include replacement of an inverted siphon at United’s Saticoy facility to increase peak diversion capacity, construction and demobilization of coastal monitoring wells near Naval Base Ventura County, Point Mugu, a pipeline along Laguna Road to connect the City of Oxnard’s advanced water purification facility (AWPF) to existing conveyance, and phase 1 of an extraction barrier project that recently reached 30% design.

The inverted siphon replacement was completed in November 2024. Coppinger said United maintained diversion capacity during construction by using bypass pumps and exercised the agency’s adequate well field storage program under FCGMA Resolution 2011-2, delivering about 1,300 acre-feet of stored surface water during the work.

United completed the coastal monitoring-well construction and demobilization in March and installed 21 monitoring points in semi‑perched Oxnard and Mugu aquifers, including 5‑inch diameter wells suitable for pilot testing pretreatment processes. The wells were pump tested in December; Coppinger said analysis is ongoing and the initial results “are generally consistent with the layering in our conceptual model and our parameters in the groundwater model.”

The Laguna Road pipeline connection is “almost complete,” Coppinger said. Interconnection valves and meters are installed, repaving is underway, and United anticipates total project completion the week after the March 26 meeting. Once operational, the interconnection is expected to allow delivery of recycled water to farms in the Pleasant Valley (PTP) area and reduce demand for pumped groundwater, a goal United has pursued for nearly a decade.

On the extraction barrier project, United received draft 30% design documents for phase 1 the week before the meeting. Coppinger said reaching 30% design “is a significant milestone” because it defines major design elements and establishes the project’s scope, budget and timeline. United is forming a technical advisory committee for phase 1 and will update the board as the project progresses.

Coppinger closed by offering a more comprehensive briefing to the board if requested.

United’s update was presented during the meeting’s public‑comment period; board members asked staff to place follow-up public‑outreach and technical discussions on a future agenda so the board and public could examine ramped‑down scenarios for Oxnard and Pleasant Valley basins and other sustainability topics.