Nelson Reservoir and Nelson Dikes Water Level

Montana · updated daily from the U.S. Bureau of Reclamation

2214.71 ft

Nelson Reservoir and Nelson Dikes is below average for this time of year and falling (-0.86 ft in the last 7 days).

Change since yesterday: -0.03 ft

Reading as of 2026-08-14 · higher than 37% of August readings on record

Where Nelson Reservoir and Nelson Dikes sits historically

TODAY 2214.71 ftRECORD LOW2207.14 ft2021-07-26RECORD HIGH2221.48 ft2024-05-06

Today's level compared with every reading in our 5.5-year record for this lake.

Since yesterday

-0.03 ft

7-day change

-0.86 ft

30-day change

-1.80 ft

1-year change

-2.15 ft

Last 30 days

2026-07-152214.4–2217.5 ft2026-08-14

Last 12 months

2025-08-142210.1–2219.1 ft2026-08-14

Full history (5.5 years)

2021-02-272205.5–2223.2 ft2026-08-13

Nelson Reservoir and Nelson Dikes records and averages

Current level2214.71 ft
Record high2221.48 ft (2024-05-06)
Record low2207.14 ft (2021-07-26)
Average of all readings2215.23 ft
Data span5.5 years (2,000 readings)

Frequently asked questions

Is Nelson Reservoir and Nelson Dikes full right now?

As of 2026-08-14, Nelson Reservoir and Nelson Dikes sits at 2214.71 ft, which is below average for this time of year.Over the past 30 days the level has fallen 1.80 ft.

What is the water level at Nelson Reservoir and Nelson Dikes today?

The most recent reading is 2214.71 ft (2026-08-14), sourced from the U.S. Bureau of Reclamation. Readings on this page refresh automatically as the agency publishes new data.

What is the highest Nelson Reservoir and Nelson Dikes has ever been?

The highest level in our records is 2221.48 ft on 2024-05-06. The lowest is 2207.14 ft on 2021-07-26. Our record covers about 5.5 years of readings.

Is Nelson Reservoir and Nelson Dikes low for this time of year?

Compared with every August in our records, the current level is higher than 37% of them — below average for this time of year. Seasonal comparison matters more than the raw number, because most reservoirs draw down predictably through late summer and refill over winter and spring.

Why is Nelson Reservoir and Nelson Dikes 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. Nelson Reservoir and Nelson Dikes has fallen 1.80 ft over the past 30 days. For the operational reason on any given week, check the U.S. Bureau of Reclamation directly.

How much has Nelson Reservoir and Nelson Dikes changed over the past year?

The level is -2.15 ft compared with this date last year (2214.71 ft today). The full-history chart above covers 5.5 years, with a record high of 2221.48 ft and a record low of 2207.14 ft.

Nearby lakes in Montana

Fresno Reservoir water level
2558.35 ft · falling
Bighorn Lake Yellowtail water level
3622.14 ft · falling
Lake Elwell and Tiber water level
2989.61 ft · falling
Canyon Ferry Lake water level
3788.92 ft · falling
Lake Frances Reservoir water level
3811.04 ft · steady
Helena Valley Reservoir water level
3817.6 ft · falling

Source: the U.S. Bureau of Reclamation. Readings are provisional and subject to revision by the publishing agency. All Montana lake levels.