Diablo Reservoir, WA

As of 2026-10-13, Diablo Reservoir sits at 1199.17 ft. Over the past 30 days the level has fallen 1.46 ft.

The most recent reading at Diablo Reservoir is 1199.17 ft (2026-10-13), sourced from the U.S. Geological Survey. Readings on this page refresh automatically as the agency publishes new data.

Readings for Diablo Reservoir run from 1197.80 ft to 1204.46 ft over the 176 days on file, which begin 2026-04-21. That window is shorter than a year, so neither end is a record for the lake. A lake's range includes a full seasonal cycle, and this gauge has not yet published one.

Reservoir levels move for four main reasons: rainfall and runoff into the basin, releases through the dam for downstream water supply, power generation or flood control, evaporation during hot months, and seasonal drawdown schedules set by the operating agency. Diablo Reservoir has fallen 1.46 ft over the past 30 days. For the operational reason on any given week, check the U.S. Geological Survey directly.

Year-over-year comparison is not available for Diablo Reservoir yet. The published series on this page covers 176 days, from 1197.80 ft to 1204.46 ft. That is not long enough to describe the lake's historical range.