"The rising water is eroding infrastructure and stranding wildlife. There’s a lot of work to be done here," South Dakota Gov. Kristi Noem (R) said after a visit to the Cheyenne River Sioux Reservation on March 25, 2019. Photo: Gov. Noem

Environment | National

Native Sun News Today: Reservations slammed by record spring flooding

Wednesday, March 27, 2019

Record spring flooding across West River reservations

Governor Noem has sent National Guard assistance

By James Giago Davies

Native Sun News Today Correspondent

nativesunnews.today

RAPID CITY— All across West River, but especially on South Dakota’s Indian reservations, spring flood waters have left thousands of people isolated, many without water, and some without even food.

Two Missouri River tributaries, the Cheyenne River, and the White River cut across West River reservations. The Cheyenne River skirts the southern Black Hills before forming the northern border of the Pine Ridge Reservation, and then turns north, forming the southern border of the Cheyenne Indian Reservation. The White River winds through the heart of the Pine Ridge Reservation, and then north of the Rosebud Reservation, an area many Sicangu families still call home.

The Cheyenne River Sioux Tribe (CRST) issued a press release on Monday alerting people to the flood stage dangers of the Cheyenne River. According to CRST, ice jams are the source of much of the overflow, and warmer weather has melted the “record snowfall,” exacerbating the problem.

The reservation was especially hard hit by the massive snow storm, which deposited up to three feet of snow, and piled up massive drifts behind 70 mph winds.

Over the weekend, I visited Pine Ridge, Porcupine, Oglala, and Wounded Knee to see the impact of the flooding. Thankful to the SD National Guard, tribal leadership, and volunteers who are working hard to help people in need. pic.twitter.com/U02iYuX5Qq
— Governor Kristi Noem (@govkristinoem) March 25, 2019

Another tributary, the Moreau River, which flows across the middle in the Cheyenne River Reservation in a series of elaborate loops and bends, is in the initial stages of dangerous flooding. Crews are struggling to keep BIA routes 2 and 7 open, according to the tribal press release.

“Crews have been working reservation wide clearing culverts and diverting drainage ditches to flow more efficiently,” the Tribe stated. “This is being done to decrease the immediate impact of flooding in low lying areas. The Cheyenne River Sioux Tribe has begun stockpiling water removal equipment, sandbags, boats and emergency supplies in anticipation of major flooding in the Moreau River valley.”

Chairman Harold Frazier also stated, “We need to continue to work together, and I commend all of our employees that have been working to ensure that our people can live and travel safely.”

In the meantime, the White River has been spilling over its banks from Oglala to White River, flooding the Highway 83 Bridge that spans the river between White River and Murdo. Many bridges across West River are similarly compromised, and people have been cautioned about attempting to cross even seemingly traversable overflows, because the submerged roadway is often dangerously eroded.

On February 13, the National Weather Service changed the flood level warning stages for West River tributaries, lowering each of the flood reaction levels by one foot, in anticipation of the impact of record snowmelt.

On Monday morning, the White River near Oacoma was measured at 22.2 feet, where it was expected to stay with some fluctuations. The flood stage is 15 feet. The Cheyenne River near Wasta was at 13.2 feet, where it was also expected to stay with some fluctuations. The flood stage is 13 feet.

Ground frozen, from Rapid City to Chamberlain, to the depth of three feet, does not readily absorb the overflow, and has contributed to the severity of the flooding.

Stream gages on area tributaries are currently reporting water levels above flood stage, and according to the national Weather Service, more rain is due midweek. Where the White river crosses over into South Dakota from Nebraska, a new peak streamflow record of 4,000 cubic feet per second has been set, eclipsing the old record of 3,820 cfs set in May of 1991.

The United States Geological Service currently has six crews on two reservations keeping timely tabs on the waterflow levels. To find a flowrate as high on the Cheyenne River near Wasta, you have to go back to 1950.