The groundwater in Cadiz originates from snowfall and precipitation at the upper reaches of the watershed in the New York Mountains, nearly 7,300 feet above sea level, that recharges the aquifer after it falls to the earth, saturates the soil and sinks into the water table more than a thousand feet below the surface. From there this water is pulled by gravity toward a 2 ½ – 3 mile narrow constriction point at the base of the watershed where Cadiz is located.
By the time this groundwater reaches Cadiz, it can be found at 200-400 feet below the surface. Without the Cadiz Water Project, the groundwater would continue its migration to the Bristol and Cadiz Dry Lakes and evaporate. The Dry Lakes act as a natural vacuum, pulling the groundwater up into the atmosphere.
Plants and animals do not use or rely on the groundwater in Cadiz, as it is too deep and beyond the root zone of any plant in the area. And on the Dry Lakes, where the groundwater is closer to the surface, the water quality is so salty and corrosive that it is too dangerous for plants and animals to consume.
Groundwater Management Plan
The Cadiz Water Project proposes to address this natural evaporation by installing wells that will intercept and rescue groundwater on its migratory pathway towards the Dry Lakes. The capture and conservation of groundwater by the project will be monitored by an extensive groundwater management plan, approved by San Bernardino County and featuring more than 100 monitoring installations and limitations on pumping. The Plan was developed by leading groundwater experts in consultation with San Bernardino County, the local government agency that has authority to implement and enforce the plan. Key measures include:
- Extensive monitoring of local water, air, springs, vegetation and land. The plan requires and provides for specific, ongoing monitoring to ensure that the technical findings and projections originally used to design, validate and approve the Project are accurate and reflect the reality of Project operations once it is implemented. This monitoring will begin at least one year before Project operations begin, will continue throughout the duration of the Project and may not end until at least 10 years after Project operations conclude. The results of this monitoring will be reported annually, will be reviewed by a panel of groundwater experts, and the panel’s findings will be made available for public review.
- Established groundwater drawdown level or “floor.” Based on a model developed by the USGS, the long-term average recharge rate for the aquifer is estimated to be 32,000 acre-feet per year. However, in an abundance of caution, the Plan includes an even more specific requirement that groundwater may not be drawn down by more than 80 feet below the current water table over a two-mile radius from the center of the Project wellfield area. This ensures that the Project will be operated sustainably and without adverse impacts to the aquifer system.
- Clear action criteria and corrective measures. Should the Project demonstrate unexpected results, the Plan provides clear criteria for authorizing corrective action and gives San Bernardino County independent, final enforcement authority over these corrective actions. The Fenner Valley Joint Powers Authority, made up of public water agencies, will also have concurrent oversight of the Project.
By actively managing the groundwater basin at Cadiz, the Project can stop the loss of groundwater, create a new water supply for 400,000 people across Southern California, and offer a new location for groundwater storage to help the region mitigate drought conditions.
To watch a video about the science of the aquifer system, click here.
To read a peer review of the Project’s science by Anthony Brown, principal hydrologist with Southern California water resources consulting firm Aquilogic, click here.