Riverside, CA – July 10, 2025 – The Santa Ana Watershed Project Authority (SAWPA) has announced the conclusion of its Cloud Seeding Pilot Program in the Santa Ana River Watershed. The decision follows a comprehensive validation report that found insufficient evidence to support a significant increase in precipitation as a result of the program’s operations.
Originally launched in November 2023, the four-year pilot aimed to explore the potential of ground-based cloud seeding to enhance local water supplies. However, after careful review of the program’s first-year data, SAWPA and its partners determined that the results did not demonstrate a strong enough correlation between cloud seeding activities and measurable increases in rainfall or snowpack.
In addition to these results, the presence of burn scars from the 2024 wildfire season across the watershed posed a heightened risk of debris flows during storm events. These conditions would have required the program to be suspended for a second consecutive year, further limiting its effectiveness and continuity.
Importantly, the decision to end the program was not influenced by health or environmental concerns. A California Environmental Quality Act (CEQA) study conducted prior to the program’s launch found no significant health or ecological risks associated with cloud seeding. This health and safety information is supported by over 50 years of similar programs conducted safely in other regions.
“SAWPA remains committed to exploring innovative, science-based solutions to enhance water resiliency in the Santa Ana River Watershed,” said Interim General Manager Karen Williams. “While the cloud seeding pilot will not continue, the agency will continue to invest in collaborative, data-driven strategies to address the region’s long-term water challenges.”
For more information, visit sawpa.gov/cloudseeding
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About SAWPA
The Santa Ana Watershed Project Authority (SAWPA), a public water agency was formed as a joint powers authority and is located in Riverside, California. SAWPA focuses on a broad range of water resource issues including water supply reliability, water quality improvement, recycled water, wastewater treatment, groundwater management, brine management, and integrated regional planning. SAWPA’s mission is to manage the Inland Empire Brine Line and to develop and maintain regional plans, programs, and projects that will protect the Santa Ana River basin water resources to maximize beneficial uses within the watershed in an economically and environmentally responsible manner. To learn more, please visit sawpa.gov.
