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Southwest Floods, But Lake Mead Stays Low
13 Oct
Summary
- Tropical Storm Rachel caused flash floods across Southern California.
- Lake Mead's water level rose only 0.1 foot during the storm.
- A 26-year drought severely impacts the Colorado River Basin.
Heavy rainfall from Tropical Storm Rachel inundated parts of the Southwest, causing significant flash and urban flooding. In San Diego, coastal areas received up to 0.95 inches of rain, while valleys saw over 2 inches, leading to widespread flooding. However, these intense downpours had a negligible impact on Lake Mead's water levels.
Between October 8 and October 11, Lake Mead's elevation increased by a mere 0.1 foot, remaining at 1,037.7 feet. This limited rise is attributed to geography, as the lake is primarily fed by the Colorado River system, which requires rainfall in specific upstream areas to replenish its supply. Most of Lake Mead's water originates from Lake Powell.
The storm's minimal effect underscores the severity of the ongoing drought in the Colorado River Basin, which has persisted for 26 years. Record-low snowpack in winter 2025-2026 caused combined storage in Lake Mead and Lake Powell to reach historic lows in August 2026. The situation at Lake Powell, with only 22 percent of its live storage capacity, illustrates the magnitude of the water deficit that a single storm cannot overcome.
