Larry Mayer/Billings Gazette
This photo from the Billings Gazette shows residents in front of the Musselshell River Sunday before it went into flood stage.
Authorities scrambled to restore road access for hundreds of people left isolated by high waters as flooded rivers in Montana and Wyoming began to recede Tuesday. Taking advantage of the lull, crews hurried to shore up sandbag flood defenses around Manderson, Wyo., and Roundup, Mont.
In Roundup, more than three dozen homes, businesses and ranches were damaged. Outside the town, as many as 400 people were cut off in rural areas after concerns over the surging Musselshell River prompted the closure of a key bridge.
"The Roundup area picked up generally one-half to three-quarters of an inch of liquid precipitation Monday and Monday night from Winter Storm Vulcan," said weather.com meteorologist Nick Wiltgen. "This includes about one to two inches of snow, with heavier amounts upriver; that snow will melt quickly."
Crews were working to restore the route Tuesday but it was unclear when it would re-open, local officials said.
There was no word on when the evacuated residents near the Musselshell could return home. A storm that began Monday night and continued early Tuesday dumped the equivalent of an inch of rain in the Roundup area.
With cooler temperatures over the past two days, the river had fallen almost 3 feet from its Monday peak.
(FORECAST: Winter Storm Vulcan)
Gov. Steve Bullock declared a flood emergency late Monday after forecasters put 30 of the state's 56 counties under some type of high water warning.
Musselshell County in central Montana appeared to be hardest hit: Dirt roads in rural areas turned to mud, some bridges were blocked by high water and the Musselshell River threatened to overcome protective dikes in Roundup.
In Richland County, two men were rescued from an ice jam after they drove up to the Yellowstone River's edge and the water began rising too quickly for them to escape, according to Tanya Fransen with the National Weather Service in Glasgow.
When local authorities decided a water rescue would be too dangerous, a helicopter from the 91st Missile Wing was called in to hoist the men to safety, said Lt. Jose Davis with North Dakota's Minot Air Force Base.
Officials advised residents to stay in place if possible, and were crafting plans to ensure sufficient food and medical supplies were available to any stranded residents.
Hundreds more in the Dean Creek subdivision southwest of Roundup also were cut off for a time until the situation improved Monday evening. But officials advised residents to remain ready to leave if necessary.
Temperatures were forecast to drop below freezing overnight as the rain turns to snow.
"If it freezes and we get snow the roads will freeze and it will help us," Gates said.
In Wyoming, six homes and two businesses suffered major damage and 11 homes had minor damage in Washakie and Big Horn counties since flooding began last week, said Kelly Ruiz, spokeswoman for the Wyoming Office of Homeland Security.
Roundup DES is actively keeping people updated on its Facebook page. They've asked concerned people to call 406-323-2777 for more information.
Seven homes were damaged in Greybull over the weekend but the extent of damage wasn't immediately clear, said Wyoming Office of Homeland Security spokeswoman Kelly Ruiz. Video posted by the homeland security office showed the river full of ice chunks on Sunday and a home protected by sand bags surrounded by water.
Mountain snowpack across both states already is well above average, setting the stage for more high water when the spring runoff arrives. That's expected in May or early June, said National Weather Service forecaster Chauncy Schultz.
Officials were keeping a wary eye on ice-jams along the Musselshell River west of Roundup, which has about 1,900 people. Ice jams also were reported on the Yellowstone, Big Horn and other rivers in Montana and Wyoming.
If the ice jams break free, water levels downstream could rise and more people in low-lying areas evacuated on short notice, Gates said. A makeshift dike in Roundup built after flooding three years ago was successfully holding back the water.
By late Monday, the Musselshell had risen to levels not seen since severe flooding damaged hundreds of homes in 2011.
Information from the Associated Press was used in this report
MORE: March Montana Floods
(Photo: Billings Gazette)