Each spring the Mono Lake Committee’s team of Mono Basin modelers and hydrology experts uses the lake level on April 1 together with the Mono Basin snowpack numbers and similar-year hydrological statistical data to produce the Mono Lake Committee lake level forecast for the runoff year ahead. You can download the full Mono Lake 2025–2026 lake level forecast here.
On April 1, 2025 the surface elevation of Mono Lake was 6383.3 feet above sea level. The lake level stayed stable through June 1. However, this forecast projects the lake will fall to 6382.8’ as the most probable lake level on April 1, 2026.
April 1 was the start of the current runoff year, which was initially classified as a “Dry-Normal II” year type, then in May was reclassified as a “Dry-Normal I” year type. The graph below shows the range of likely Mono Lake elevations for the runoff year. The range of projections (light blue shading) is produced by the Mono Lake Committee’s modeling of hydrologic sequences using a variety of similar runoff years, with the most probable (solid blue line) level based on slightly-adjusted conditions from the most similar past runoff year (1991).
The Los Angeles Department of Water & Power (DWP) plans to divert and export the maximum allowed volume of water this year—16,000 acre-feet. This surface export volume represents 0.35 vertical feet of Mono Lake and is water diverted at a time when Mono Lake is not rising toward its mandated, and urgently-needed, 6392-foot management level. In total, Mono Lake will lose about half a foot of elevation due to DWP’s combined surface and groundwater exports.
Reference lake levels and exports
- State Water Board mandated lake level to protect Mono Lake: 6392 feet above sea level.
- Lake level rise from April 1, 2025 needed to achieve the mandated level: 8.7 feet.
- Groundwater exports in the form of a constant flow in the Mono Craters Tunnel, total about 5,000 acre-feet of additional water to leave the Mono Basin annually.
Top photo courtesy of Annie Schmidt.