Recent rains, combined with warm spring weather that caused snow to melt earlier than normal, have quickly filled Buffalo Bill Reservoir and forced officials to release large quantities of water into …
Recent rains, combined with warm spring weather that caused snow to melt earlier than normal, have quickly filled Buffalo Bill Reservoir and forced officials to release large quantities of water into the Shoshone River. The releases have pushed the river to its capacity.
It’s impossible to ignore the roar of thousands of cubic-feet of water being released at the 350-foot dam west of Cody. Mist from the release fills the air to the top of the dam as both gates were open Monday and Tuesday. The Bureau of Reclamation released 8,000 cubic feet per second (CFS) Monday, with the reservoir water level 1.14 feet from capacity and “coming up,” said Jay Dallman, a spokesman for the Bureau of Reclamation in Wyoming.
“It’s a little bit of a juggling act,” Dallman said.
The water level “dropped below average because April and May runoff just didn’t amount to what we thought it was going to amount to,” he said. “And now with recent rains, it is kicked back up into a high runoff category again.”
By Tuesday the releases were cut back to 7,000 CFS — and that was decreased again to 5,000 CFS by Wednesday morning. Inflows into the reservoir were about 11,000 CFS Tuesday.
“So although the 8,000 was a big number, that’s actually less than what would have happened if the dam wasn’t there,” Dallman said.
There’s a chance of rain and thunderstorms forecast in the area through early next week and releases could increase again if needed. Managers are quick to adjust releases to ensure water levels in the reservoir never reach dangerous levels. At the same time, they work to maintain high enough water levels to supply the northern Big Horn Basin’s agriculture industry with water through the traditionally dry months of July and August.
The Bureau of Reclamation works closely with local meteorologists and were prepared for the large amount of runoff well before it arrived, said Mike Follum, branch chief of the Water and Civil Works Branch of the agency in the state. When the bureau officials realized there was a chance of significant runoff, they planned to test spillway gates as they increased releases. Only about 10% of releases flow through the spillway gates during the tests. The dam has two main 4x5 gates, the spillway gates and power units that also take water from the dam.
Follum also works closely with Park and Big Horn County officials, as well as area irrigation districts. He was in Cody Tuesday as they tested the spillway gates and then traveled the Shoshone River Valley looking for flooding issues, spending time with Big Horn County officials before heading back to Casper.
“Emergency management at the county level are partners in this and they did a fantastic job of warning the public of the increased outflows,” Follum said. He also praised irrigation district managers for their continual cooperation during periods of high outflows.
In response to increased water in the Shoshone River, both Park and Big Horn counties released safety guidelines to the public.
“Please be incredibly cautious while near rivers and streams,” the Park County Sheriff’s Office advised.
Both counties asked residents to be aware that riverbanks may have destabilized — and to watch out for children, livestock, pets and equipment in low-lying areas. Be cautious with recreational activities for the immediate future, they advised, until water levels have reached a normal level.
The last time release rates from Buffalo Bill Dam hit 8,000 CFS was in 2018. The record release at the dam is 14,000 CFS in 1981.