The torrential rainfall and record-setting snow of the past winter did much to alleviate California’s three-year drought. However, unlike most of the state, all of our water in the mid-Santa Cruz region comes from rainfall that percolates into the ground and becomes groundwater. Groundwater basins take years to be replenished by rainall. For those that rely entirely on groundwater for their water supply, one year of above-average rainfall does not make up for years of drought and decades of over-pumping our groundwater basin.
The Soquel Creek Water District, which relies exclusively on groundwater, shares the Santa Cruz Mid-County Groundwater Basin with other water users, including the city of Santa Cruz, Central Water District, small mutual water companies, and private well owners. In accordance with the State Groundwater Management Act (SGMA), the Santa Cruz Mid-County Groundwater Agency (MGA) was formed in 2016 to manage the basin and ensure that all water users have access to a safe and reliable water supply. In addition, because the basin is designated as “critically overdrafted” – the MGA is mandated to prepare an Groundwater Sustainability Plan and perform annual reports to demonstrate the basin will be sustainable by 2040.
The draft annual report is required to be submitted to the state on April 1 and was presented to the MGA at its March meeting.
Findings included in the Report for Water Year 2022 included:
- Groundwater levels at most wells declined or remained similar to the previous year.
- There are undesirable results for seawater intrusion because 7 coastal representative monitoring points with 5-year moving average groundwater elevations are below their respective minimum threshold groundwater elevation proxies.
- Chloride concentrations at 4 monitoring wells have exceeded minimum thresholds for seawater intrusion
- Net groundwater extraction remains greater than sustainable yields in 2 of 3 aquifer groups
Thus, the MGA notes in the report that seawater intrusion continues to occur and remains an issue to mitigate. The report also describes how the MGA is moving in several positive actions with its programs, activities, and projects within the basin. Among those are:
- Pure Water Soquel (PWS) – Construction of purified recycled water project continues with anticipated start up in 2024
- Aquifer Storage and Recovery (ASR) – Pilot testing started in WY 2022 and will end in November 2024. For a full scale project, the City is working with the State on its water rights petition.
- Water Transfers / In-Lieu Groundwater Recharge – an extension of the pilot project agreement runs through May 1, 2026
The Pure Water Soquel project is the primary project in the Groundwater Sustainability Plan since it’s currently being implemented. What is Pure Water Soquel? While we have described it previous columns, we still come across community members who haven’t heard a lot about this important project! Here are some project details:
- PWS will take highly treated wastewater – which would otherwise be discharged to the Monterey Bay National Marine Sanctuary – and purify it using a proven multi-step treatment process.
- Purified recycled water is already being used for groundwater recharge in other parts of California, including Monterey, and other parts of the world.
- Purified recycled water is safe and clean, and it will be tested regularly to ensure it meets all state and federal drinking water standards. The purification process includes ozone, microfiltration, reverse osmosis, and ultraviolet light with advanced oxidation, which is near-distilled quality of water.
- The PWS new Water Purification Center is being built near Highway 1 and Chanticleer Avenue. The water will then be conveyed to three Seawater Intrusion Prevention Wells to replenish the groundwater basin and create a barrier against seawater intrusion.
For more information on Santa Cruz Mid County Groundwater Agency and the 2022 Annual Report, visit their website.