IA00779-ARNOLD-ARMSTRONG-SUBWTRSHD-STA-2-05-3 RESERVOIR REPORT

Last Updated: January 12, 2026

The overall status of the nation's dams and reservoirs reflects a diverse range of storage levels, with some bodies of water experiencing above-average storage while others fall below historic averages. Notably, several key reservoirs show significant variances that may impact regional water management and ecosystems.

For instance, Lake Mead in Nevada – a critical water source for millions in the Southwest – is considerably below its average storage capacity at 8,671,468 acre-feet, a stark contrast to its historic average of 17,984,398.93 acre-feet. Similarly, Elephant Butte Reservoir in New Mexico holds just 188,909 acre-feet compared to an average of 829,181.99 acre-feet, signaling potential water scarcity issues. On the flip side, Lake San Antonio in California stands at a surplus with 270,863 acre-feet against an average of 132,675.92 acre-feet, reflective of recent hydrologic events or management strategies that have resulted in increased storage.

These disparities in reservoir levels underscore the complex interplay between climatic variables, such as precipitation and snowpack melt, and human interventions like water consumption and reservoir management. Hydrologists and water managers must continuously monitor these changing conditions to ensure sustainable water allocation and maintain ecological balance, particularly in regions facing drought conditions or those with reservoirs atypically high for the season.