What shortage tier is the Colorado River in for 2026?

For calendar year 2026, a Shortage Condition under Section 2.D.1.a of the 2007 Interim Guidelines (the first shortage tier, for a projected January 1 Lake Mead elevation below 1,075 ft and at or above 1,050 ft) governs Lake Mead operations, together with 2019 Drought Contingency Plan contributions. Source: Reclamation's July 2026 24-Month Study.

What are the Lake Mead shortage tier levels?

The 2007 Interim Guidelines set three shortage tiers keyed to Lake Mead's projected January 1 elevation: below 1,075 ft (Lower Basin apportionment cut to 7.167 maf), below 1,050 ft (7.083 maf), and below 1,025 ft (7.0 maf), versus a normal 7.5 maf. The 2019 DCP adds further contributions starting at 1,090 ft. Sources: 2007 Interim Guidelines ROD Section 2.D; LB DCP Agreement Table 1.

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Colorado River Shortage Tiers

The fixed Lake Mead thresholds — 1,075 / 1,050 / 1,025 feet — and what governs operations in 2026.

Lake Mead's elevation is 1,041.38 feet as of July 23, 2026 — 33.62 ft below the 1,075 ft threshold, 8.62 ft below the 1,050 ft threshold, 16.38 ft above the 1,025 ft threshold.
For calendar year 2026, a Shortage Condition under Section 2.D.1.a of the 2007 Interim Guidelines (the first shortage tier) governs Lake Mead operations, together with Drought Contingency Plan contributions — per Reclamation's July 2026 24-Month Study.
Shortage tiers are set from the projected January 1 elevation in the August 24-Month Study — not from the daily gauge reading.

How the tiers work

The December 2007 Colorado River Interim Guidelines for Lower Basin Shortages and Coordinated Operations for Lake Powell and Lake Mead (the "2007 Interim Guidelines") define three shortage tiers keyed to Lake Mead's projected January 1 elevation. In a normal year the Lower Division states are apportioned 7.5 million acre-feet (maf): 2.8 maf Arizona, 0.3 maf Nevada, 4.4 maf California. Under shortage, the total is reduced as follows (California's 4.4 maf is unchanged by the 2007 tiers):

Projected Jan 1 Mead elevation	Lower Basin total	Arizona	Nevada
below 1,075 ft to 1,050 ft	7.167 maf	2.48 maf (−320,000 af)	287,000 af (−13,000 af)
below 1,050 ft to 1,025 ft	7.083 maf	2.40 maf (−400,000 af)	283,000 af (−17,000 af)
below 1,025 ft	7.000 maf	2.32 maf (−480,000 af)	280,000 af (−20,000 af)

Source: 2007 Interim Guidelines Record of Decision, Section 2.D (usbr.gov PDF).

2019 Drought Contingency Plan additions

The 2019 Lower Basin Drought Contingency Plan (DCP) layers additional required contributions on top of the 2007 tiers, beginning when Lake Mead is projected at or below 1,090 feet (Arizona 192,000 af, Nevada 8,000 af). California contributions begin at or below 1,045 feet (200,000 af, rising to 350,000 af at or below 1,030 feet). Combined 2007-Guidelines-plus-DCP volumes reach 1,100,000 af below 1,025 feet. Source: Lower Basin DCP Agreement, Table 1 (usbr.gov PDF; overview at usbr.gov/dcp).

What applies right now

Reclamation's July 2026 24-Month Study states that, based on the August 2025 projection of the January 1, 2026 elevation (below 1,075 ft and above 1,050 ft), a Shortage Condition consistent with Section 2.D.1.a governs Lake Mead for calendar year 2026, together with DCP contributions under Section III.B of the LB DCP Agreement. Lake Powell is in the Mid-Elevation Release Tier for water year 2026, with its annual release reduced to 6.0 maf. Source: July 2026 24-Month Study; the CY 2026 determination was made in the August 2025 24-Month Study.

Live context: Lake Mead is at 1,041.38 ft as of July 23, 2026 — see the Lake Mead page for the daily series. These rules expire at the end of 2026; see the post-2026 guidelines process.

This page describes the operative rules and where the gauge stands against fixed thresholds. It makes no predictions about future tier determinations.