March water supply reported 

The U.S. Department of Agriculture (USDA) Natural Resources Conservation Service (NRCS) published the March 2024 Wyoming Basin and Water Supply Outlook Report on March 1. 

This report analyzes snowpack, precipitation, streamflow and reservoir storage across the state of Wyoming. 

The report also assesses the water supply outlook for the entire state of Wyoming, as well as individual basins including the Snake River, Madison Headwaters, Yellowstone River, Wind River, Big Horn River, Shoshone River, Powder River, Tongue River, Belle Fourche River, Cheyenne River, Upper North Platte River, Lower North Platte River, Laramie River, Sweetwater River, South Platte River, Little Snake River, Upper Green River, Lower Green River and Upper Bear River basins.

Snowpack and precipitation

As of March 1, snow water equivalent (SWE) across the state was 68 percent of median, which remains unchanged from the February report. The highest SWE was reported in the Upper Bear River Basin at 113 percent of median, and the lowest SWE was reported in the Belle Fourche River Basin at 35 percent of median. 

According to NRCS, the Belle Fourche River, Cheyenne River, South Platte River, Powder River, Tongue River, Yellowstone River, Lower North Platte River, Big Horn River, Shoshone River, Upper Green River, Laramie River and Madison Headwater basins were below 90 percent of the median SWE recorded from 1991 to 2020.

Additionally, the report notes the Sweetwater River Basin had the highest precipitation for the month at 203 percent of median, while the Belle Fourche River Basin had the lowest precipitation for the month at 49 percent of median. 

Streamflow

NRCS forecasts streamflow yields from April through September across Wyoming basins – excluding streamflow in the Green, Little Snake and Cheyenne basins – to average 96 percent. Streamflow yields at these three basins are expected to respectively average 91 percent, 108 percent and 51 percent from April through July. 

Median streamflow yields from April through July are forecast to average 51 percent for the Cheyenne River Basin, 75 percent of median for the Tongue River Basin, 80 percent of median for the Powder River Basin, 84 percent of median for the Yellowstone River Basin and 87 percent of median for the Snake River Basin. 

Further, the report shows yields will average 93 percent for the Laramie River Basin, 94 percent for both the Shoshone River and Upper North Platte River basins and 96 percent for the Lower North Platte River Basin.

Yields from the Wind River, Big Horn River and Sweetwater River basins is forecast at 106 percent, 108 percent and 124 percent, respectively.

Reservoir storage

For the entire state of Wyoming, NRCS reports average reservoir storage at 104 percent of median, which remains unchanged from the February report. 

All reported reservoirs were near or above the median.

According to NRCS, reservoirs in the Snake River, Lower Green River, Big Horn River, Cheyenne River, Lower North Platte River and Wind River basins reported numbers at 98 percent, 100 percent, 102 percent, 102 percent, 103 percent and 104 percent, respectively. 

The Buffalo Bill Reservoir in the Shoshone River Basin and reservoirs in the Belle Fourche River Basin both reported numbers near median at 108 percent. 

Additionally, reservoirs in the Upper Green River and Upper North Platte River basins reported higher numbers, at 112 percent and 117 percent, respectively. 

Hannah Bugas is the managing editor of the Wyoming Livestock Roundup. Send comments on this article to roundup@wylr.net.