American Falls Reservoir water level
▲ 1.9 points from 3.4% a year ago
Source: data.usbr.gov/rise/api/catalog-item/129133, accessed October 1, 2026. Updated every 6 hours.
American Falls Reservoir is at 4.7% of full pool (4308.83 ft) as of September 27, 2026. American Falls Reservoir was last full on May 25, 2025 (95.2% of normal storage). American Falls Reservoir is near American Falls, Idaho.
American Falls Reservoir level history
This site counts a reservoir as full on a day its storage is at or above 95% of the dam's normal storage (National Inventory of Dams). Many reservoirs rarely reach 100%, even in wet years, because operators release water for irrigation, power or flood control before they fill, so this site treats 95% as full. Highs and lows are daily readings in the published data, not official records. Source: Bureau of Reclamation daily data.
Storage, % of full pool, since 1925
American Falls Reservoir is rising: 4.1% full, up 0.7 percentage points since September 20, 2026.
On this same date last year (September 28, 2025), American Falls Reservoir was 3.4% full, 0.7 percentage points lower than today's 4.1%.
Weekly averages of the source's daily readings; older years may be monthly or sparser where that is all the source published. Download the charted data (JSON).
American Falls Reservoir map
American Falls Reservoir is at 42.7794, -112.8743. Open in OpenStreetMap.
The dam
- Flood control
- Recreation
Sources: nid.sec.usace.army.mil, accessed September 29, 2026
On the water
No campgrounds, boat ramps, or swim spots linked to American Falls Reservoir yet.
Common questions
- American Falls Reservoir is at 4.7% of full pool (4308.83 ft) as of September 27, 2026.
- American Falls Reservoir was last full on May 25, 2025, when it held 95.2% of its normal storage (elevation 4,353.07 ft). This site counts a reservoir as full on a day its storage is at or above 95% of the dam's normal storage (National Inventory of Dams). Many reservoirs rarely reach 100%, even in wet years, because operators release water for irrigation, power or flood control before they fill, so this site treats 95% as full. Based on Bureau of Reclamation daily data since October 1, 1925.
- In Bureau of Reclamation daily data since October 1, 1925, American Falls Reservoir's highest elevation was 4,355.75 ft on June 20, 1963. Its lowest after it first filled (June 17, 1927) was 4,295.6 ft on September 29, 1977. These are the highest and lowest daily readings in the published data, not official records.
- American Falls Reservoir is near American Falls, Idaho (42.7794, -112.8743).
- Bureau of Reclamation operates the dam at American Falls Reservoir.
- American Falls Reservoir's dam is used for Flood control, Recreation.