CALIFORNIA RESERVOIR REPORT

Last Updated: December 28, 2025

California's dam and reservoir system is currently experiencing a mix of conditions, reflective of recent weather patterns and ongoing water use issues. As Southern California welcomed sunshine after heavy storms, rain loomed again for the New Year, impacting water storage levels in various reservoirs. For instance, Lake Havasu near Parker Dam showed a storage level slightly lower than average, with a current gage height of 47 feet compared to its average of 48.41 feet. Similarly, Leviathan Mine Pit Flow and Ponds near Markleeville also recorded lower gage heights than their averages. In contrast, Bridgeport Reservoir near Bridgeport and San Vicente Res near Lakeside reported water surface elevations higher than typical levels for this period. This indicates an influx of water possibly due to recent torrential rains and atmospheric storm conditions experienced across the state.

The abnormal conditions observed in certain reservoirs like Lake San Antonio, which is currently at 270,863 acre-feet versus its average 132,675.92 acre-feet, and Lake Oroville, whose current levels are not provided, underscore the challenges in water management amidst fluctuating climatic events. These conditions could be attributed to the wettest Christmas Eve and Day ever recorded in Southern California, which brought about mudslides and flash floods. Meanwhile, areas like Donnell Lake near Dardanelle and Beardsley Lake near Strawberry have seen significant drops in water surface elevations, potentially impacted by the state's water use complications and ongoing discussions about water allocation along the Colorado River. As California enters 2026, the recent weather extremes and their effects on reservoirs and dams highlight the state's vulnerability to climate variability and the importance of strategic water resource management.

California has over 1,400 reservoirs and dams, which provide water for agriculture, industry, and households. Some of the major reservoirs in the state include Lake Oroville, Shasta Lake, and San Luis Reservoir. These reservoirs are fed by streams, rivers, and creeks such as the Feather River, Sacramento River, and San Joaquin River. The snowpack in the Sierra Nevada mountains is a crucial source of water for these reservoirs, as it melts during the spring and summer and fills the streams and rivers that flow into the reservoirs. However, drought conditions have been a major concern in recent years, with record low levels in some reservoirs. Seasonal trends show that reservoirs are typically at their lowest levels in the fall and winter, and reach their highest levels in the spring and summer. Overall, California’s reservoirs and dams play a vital role in managing the state’s water resources and ensuring a reliable water supply for its residents.

California has over 1,400 reservoirs and dams, which provide water for agriculture, industry, and households. Some of the major reservoirs in the state include Lake Oroville, Shasta Lake, and San Luis Reservoir. These reservoirs are fed by streams, rivers, and creeks such as the Feather River, Sacramento River, and San Joaquin River. The snowpack in the Sierra Nevada mountains is a crucial source of water for these reservoirs, as it melts during the spring and summer and fills the streams and rivers that flow into the reservoirs. However, drought conditions have been a major concern in recent years, with record low levels in some reservoirs. Seasonal trends show that reservoirs are typically at their lowest levels in the fall and winter, and reach their highest levels in the spring and summer. Overall, California’s reservoirs and dams play a vital role in managing the state’s water resources and ensuring a reliable water supply for its residents.