About the Big Hole River Drought Management Plan
Shared Sacrifice, Shared Success
The Big Hole River Drought Management Plan designates target river flow and temperature conditions for fish health in five river sections of the Big Hole River. The plan includes voluntary conservation targets for all water users, MFWP fishing restriction criteria, and information tools. Conservation actions are designed support the health of the fishery.
The plan outlines voluntary conservation actions and relies on Shared Sacrifice, Shared Success – if all users sacrifice, we can all be successful in protecting the fishery. The plan also designates MFWP fishing restrictions when drought conditions reach critical levels.
The BHWC DMP originated in 1997. The plan is reviewed annually by a committee made up of irrigators, fishermen, conservation groups, and agency representatives as well as the entire BHWC.
Provided by Matt Norberg, Montana Department of Natural Resources and Conservation as of November 20, 2019.
2019 Water Year Highlights
- Big Hole Basin snowpack: approx. 96% of average (1981-2010 median)
- February broke records across MT for snowfall and cold temps
- March was the opposite – minimal snowfall
- Seasonal April conditions led to low to mid elevation runoff
- Snowpack went isothermal by end of April (even at high elevations)
- Jefferson basin precipitation YTD – approx. 104% of average
- 69 inches average
- 2019: 10.8 inches, ~90% of average
- April to June: ~77% of average
- May to June: ~57% (we usually get a lot of rain during this time period, but that didn’t happen this year)
- July to September: ~160% of average (2.49 inches of rain)
- June/July/August: 87% of average (this is the critical time period when moisture is really needed)
- Wisdom Temperatures:
- February and March: -5 and -9.5 degree Fahrenheit departure from normal
- April to June: 98%
- July to August: 98%
- September: 101%
- Peak flows:
- Melrose: 5,940 cfs, May 18 (2-3 weeks early)
- Wisdom: 1,450 cfs, April 21 (5-6 weeks early)
- Bankfull: 1,100 cfs, 3 days above bankfull conditions (channel is full and water is just about to spill onto the floodplain – this is really important for natural channel maintenance to occur.)
- In comparison, in 2018, we had 144% snowpack and 48 days above bankfull.
- Low flows:
- Melrose: 251 cfs, September 5
- Wisdom: 14.4 cfs, September 5
2019 USGS Gage Bill:
Water Temperature at Big Hole River @ Wise River (Dickie Bridge), Maiden Rock, and Notch Bottom (Glen):
USGS Flow Gages for Upper Big Hole CCAA program:
The Wise River real-time gage was installed near the mouth of the Wise River October 2015. The Big Hole Watershed Committee sought installation in order to continue flow and temperature monitoring in the Wise River, as well provide information for Wise River irrigators. The gage reports flow, stage and water temperature in real-time via Montana Bureau of Mines and Geology Surface Water website. The gage is part of the 2015 launch of DNRC & Montana Bureau of Mines and Geology real-time monitoring system for small streams, who installed and operates the gage. Funding was provided by Big Hole Watershed Committee, The Nature Conservancy, and Montana Trout Unlimited and is graciously hosted on the PKR Ranch. The Big Hole Watershed Committee in partnership with DNRC, MFWP, and Montana Bureau of Mines and Geology have been conducting monitoring of the Wise River surface and groundwater since 2011.