Drought concerns minimal in Montana, says DNRC

Drought concerns minimal in Montana, says DNRC

Source: Billings Gazette
Click here to read the article: http://billingsgazette.com/news/state-and-regional/montana/drought-concerns-minimal-in-montana-says-dnrc/article_b9e8312f-813c-532b-bc82-9bc9e0a5a261.html

Gazette Staff

Montana’s 2017 water year will be the best in several years, with minimal drought concerns for the growing season, and water supplies in excess of normal in the Flathead and Bighorn River basins, according to the Governor’s Drought and Water Supply Advisory Committee.

“Drought will not be an issue this year,” said Ada Montague, DWSAC’s staff and a water planner with the Montana Department of Natural Resources and Conservation. “Wibaux and Fallon counties are slightly dry at this time, along with Fergus, Judith Basin, Silver Bow and Jefferson, but we continue to get timely spring rain, reducing concern in those areas.”

Montague said staff will continue to monitor conditions in the Sun, Judith and Smith river sub-basins, along with Hyalite Creek and the Upper Clark Fork, for any signals of returning drought. These areas experienced early runoff and low stream flows the previous two years and showed below-average snow accumulations earlier this winter.

Flooding, on the other hand, is a concern. The May through July forecast for Yellowtail Dam on the Bighorn River is 278 percent of average flows. April inflows topped 412 percent of average, and May inflows at 382 percent of average. As a result, 13,900 cubic feet per second are being released from Yellowtail Dam in hopes of controlling flooding. Montague said those high flows will likely continue through July. The Bureau of Reclamation is monitoring upstream and downstream conditions in its management of Yellowtail Dam and is holding weekly stakeholder calls to ensure coordination.

Flooding on the Flathead River is also likely this spring and early summer. The Flathead has Snow Water Equivalent measurements of 125 percent of normal and stream flow volume forecasts indicate flows of 146 percent of normal. Flathead Lake was at 66 percent of capacity at the end of April with Hungry Horse releasing 10,400 cfs of total discharge. Since then, Flathead Lake has filled to an elevation of 2,890.5 feet, just under 3 feet from full. There is between 40,000 to 50,000 cfs coming in and 40,000 cfs leaving, allowing for a gradual fill. The lake will fill by the July Fourth holiday and will remain at that level until it is lowered in the fall. However, localized flooding is anticipated this season and water users should be prepared.

Elsewhere in the state, moisture across northwest Montana (Blaine, Phillips, Valley, Daniels and Sheridan counties) is slightly above average, as are five counties in south-central Montana (Sweet Grass, Stillwater, Carbon, Yellowstone and Treasure). The remainder of the state is rated at or near normal.