MWD conditions 440,000 AFY Colorado River reduction on firm access to Lake Mead storage

MWD conditions 440,000 AFY Colorado River reduction on firm access to Lake Mead storageThe Metropolitan Water District is pushing for guaranteed access to its 1.6 million acre-feet of Intentionally Created Surplus below the 1,025-foot elevation threshold, warning that discretionary federal access will shift dry-year reliability risks onto the district.

California has proposed taking 440,000 acre-feet of annual reductions in 2027 and 2028 as part of a 1.25 million acre-foot Lower Basin plan to address system losses.

MWD's support is strictly contingent on securing rules-based, rather than discretionary, access to its Intentionally Created Surplus (ICS) when Lake Mead falls below 1,025 feet.

With intra-California agreements still pending, MWD may have to act as a 'backstop' for the state's reduction commitments if other contractors face environmental compliance delays.

Lake Mead is forecast to drop to 1,035 feet by the start of 2027, nearing the critical threshold where the Interior Secretary asserts authority to restrict stored water deliveries.

The Metropolitan Water District (MWD) is conditioning its participation in proposed Lower Basin Colorado River reductions on securing firm, rules-based access to its stored water in Lake Mead, according to a July 8 update provided to the West Basin Municipal Water District caucus. Under a three-state proposal to address evaporative and system losses in 2027 and 2028, the Lower Basin would take 1.25 million acre-feet of annual reductions. California's share would be 440,000 acre-feet per year, alongside a commitment for 300,000 acre-feet of voluntary conservation backed by federal funding. However, Shanti Rosset, MWD's Colorado River Resources Policy Manager, told directors that California's willingness to take out-of-priority cuts is strictly contingent on the federal government guaranteeing access to Intentionally Created Surplus (ICS) water when Lake Mead drops to critically low levels. MWD currently holds approximately 1.6 million acre-feet of ICS banked in Lake Mead. The conflict centers on a reservoir elevation band between 1,025 and 1,000 feet, where the U.S. Interior Secretary currently asserts discretionary authority to reduce or deny stored water deliveries. Lake Mead is forecast to drop to 1,035 feet by the start of 2027. "A savings account is only worth what you can withdraw," Rosset said, noting that discretionary access would shift dry-year reliability risks directly onto MWD. "Out-of-priority reductions without firm recovery of our stored water moves risk onto us." MWD is pushing for a withdrawal process based on objective criteria and firm timelines. Securing this access is particularly critical because MWD may be forced to act as a backstop for California's overall reduction commitments. California contractors have not yet reached an internal agreement on how to divide the state's 440,000 acre-foot obligation. Rosset noted that if agricultural contractors like the Imperial Irrigation District face delays in securing environmental compliance for their reduction programs, MWD may have to step in during the initial months to ensure the state meets its targets. The federal Record of Decision for post-2026 operations was initially targeted for late July, though MWD staff noted the deadline may slip closer to the end of the water year on September 30. MWD's board is tentatively expected to review implementation agreements by September.