MACKAY Reservoir Water Level

Idaho · updated daily from the U.S. Geological Survey

40.32 ft

MACKAY Reservoir is current reading available and falling (-3.85 ft in the last 7 days).

Change since yesterday: -0.42 ft

Reading as of 2026-08-15

Where MACKAY Reservoir sits historically

TODAY 40.32 ftRECORD LOW40.32 ft2026-08-15RECORD HIGH61.55 ft2026-06-01

Today's level compared with every reading in our 0.3-year record for this lake.

Since yesterday

-0.42 ft

7-day change

-3.85 ft

30-day change

-14.93 ft

1-year change

— ft

Last 30 days

2026-07-1638.5–57.0 ft2026-08-15

Last 12 months

2026-04-1737.8–64.1 ft2026-08-15

MACKAY Reservoir records and averages

Current level40.32 ft
Record high61.55 ft (2026-06-01)
Record low40.32 ft (2026-08-15)
Average of all readings57.21 ft
Data span0.3 years (121 readings)

Frequently asked questions

Is MACKAY Reservoir full right now?

As of 2026-08-15, MACKAY Reservoir sits at 40.32 ft, which is current reading available.Over the past 30 days the level has fallen 14.93 ft.

What is the water level at MACKAY Reservoir today?

The most recent reading is 40.32 ft (2026-08-15), sourced from the U.S. Geological Survey. Readings on this page refresh automatically as the agency publishes new data.

What is the highest MACKAY Reservoir has ever been?

The highest level in our records is 61.55 ft on 2026-06-01. The lowest is 40.32 ft on 2026-08-15. Our record covers about 0.3 years of readings.

Why is MACKAY Reservoir low right now?

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. MACKAY Reservoir has fallen 14.93 ft over the past 30 days. For the operational reason on any given week, check the U.S. Geological Survey directly.

How much has MACKAY Reservoir changed over the past year?

Year-over-year comparison is not available for this lake yet. The full-history chart above covers 0.3 years, with a record high of 61.55 ft and a record low of 40.32 ft.

Nearby lakes in Idaho

Lake Walcott water level
4243.9 ft · steady
Mud Lake water level
4.66 ft · falling
American Falls Reservoir water level
4315.87 ft · falling
Milner Lake water level
11.24 ft · steady
Anderson Ranch Reservoir water level
4162.17 ft · falling
Ririe Reservoir water level
5088.12 ft · falling

Source: the U.S. Geological Survey. Readings are provisional and subject to revision by the publishing agency. All Idaho lake levels.