Oglala Sioux Tribe officials are asking the public to prepare for evacuations near the White Clay and Oglala dams.
Floodwaters are drenching the Pine Ridge Reservation and have washed out waterlines in several communities.
Meteorologists say the worst flooding in the area should be over.
Officials say seven communities in the Pine Ridge reservation are without water. Over the weekend Governor Kristi Noem activated 13 members of the South Dakota National Guard to distribute water.
Abrupt snowmelt from Black Hills and water from the White River in Nebraska are flooding the area, leaving some tribal members stranded.
Peri Pourier is executive director of Pine Ridge Relief, an organization created to coordinate volunteers and resources. She says the communities need food.
“We have approximately ten shelters—infrastructure that’s already in place—to use as shelters,” Pourier says. “The displaced families—women, men, children, babies—needing that food, the water, and basic supplies since they’ve been displaced from their homes.”
Pourier says horseback riders are piling up resources and reaching isolated communities that are blocked off from flood waters.
Pourier says the reservation is already low on resources, so emergencies like this hit the reservation even harder.
Officials with the Rosebud Sioux Tribe are also dealing with floodwaters because of quick snowmelt.
Over the weekend the Hidden Timber Dam broke in Todd County. The community is dealing with flooding on highway 83 and county roads washed out.
Shaun Bordeaux is a state representative who represents portions of Rosebud in the statehouse. He says he’s never seen flooding like this.
“And just uptown in the town of Mission we got flooding that goes right up to our old football field that we practiced on, and city park and places like this that have had some flooding a little bit over the banks, but we’re talking big, wide, expansive areas that have never seen flooding before… at least not in my 51 years. It’s probably a record amount of water we have here.”
Bordeaux says the flooding shows the environment is fragile. He says the tribal communities are concerned how the pending Keystone XL pipeline could handle this kind of flooding.
Katie Porjorlie is a meteorologist with the National Weather Service in Rapid City. She says flood gagues along the White River are still high, but there’s some positive news.
“The one at the Nebraska line is still at major flood stage, and it looks like that will continue for a little bit but it’s going down,” Porjorlie says.
Porjorlie says a warmup later this week could melt the rest of the snow in Pine Ridge, but that shouldn’t impact flooding too much. She says most of the snow has already melted.