Portneuf River at Pocatello

1. 10.00 ftSignificant flooding of agricultural land will occur from the Inkom and Blackrock area. Lowland flooding will occur along sections of the river in Pocatello from Portneuf Gap to the Cheyenne Avenue Bridge and downstream of the concrete channel beginning at Sacajawea Park.
2. 9.40 ftWater will encroach around sitting benches near the river at the Pacific Recycling Trailhead.
3. 9.15 ftFlooding of low lying agricultural land and pasture will occur in the Inkom and Blackrock area. Lowland flooding is likely along sections of the river between Portneuf Gap and the Cheyenne Avenue Bridge in Pocatello.
4. 8.50 ftSections of Sacajawea Park will be under water and the trail is usually closed at this level. Marsh Creek near Inkom may also be over its banks.
5. 8.00 ftWater will encroach onto portions of the bike and walking trail next to the river in Sacajawea Park in Pocatello.

Chance of flooding, September to November

The three-month chances are the River Forecast Centers’ long-range flood outlook, issued September 27, 2026.

Most recent crests

• May 30, 2023: 11.14 ft
• May 8, 2022: 5.43 ft
• March 20, 2021: 5.31 ft
• May 2, 2020: 6.97 ft
• April 27, 2019: 9.26 ft
• April 30, 2018: 8.66 ft
• May 14, 2017: 9.83 ft
• April 15, 2016: 7.33 ft
• February 9, 2015: 5.13 ft
• February 16, 2014: 7.35 ft

• UpstreamPortneuf River at Topaz
• DownstreamPortneuf River at Tyhee
• Portneuf River
• Spring Creek (Eastern ID) at Fort Hall
• Snake River at Blackfoot (Tilden Bridge-Ft. Hall)
• Blackfoot River at Blackfoot (Butte Road-Ft. Hall)
• Marsh Creek (Eastern ID) at McCammon
• Eastern Idaho Reservoirs at American Falls
• Snake River at Neeley

Forecasts by the Northwest River Forecast Center. Forecasts are issued routinely year-round. Stage may be affected by ice during winter months.

Stage, flood stages, impacts and crest history from NOAA’s National Water Prediction Service. Streamflow and the daily record from the U.S. Geological Survey.