Gov. Noem issues emergency declaration after eastern SD floods

Gov. Kristi Noem has declared a state of emergency for parts of South Dakota, following recent storms and associated flooding on the eastern side of the state.

Noem signed the declaration Saturday evening, stating in a press release that state agencies continue to assist local governments throughout the emergency.

“Even though the rain is slowing down, we need to keep vigilant. The worst of the flooding along our rivers will be Monday and Tuesday,” Noem stated in the release. “Check SD511.org for updates on road conditions, and please reach out to your county emergency manager if you have immediate needs.”

Noem said in a press conference early Saturday morning that the flooding event's "crest" — the highest level of water flows — is expected to hit the region's rivers and streams Monday and Tuesday, depending on the area.

More: Gov. Noem, state officials say eastern SD river levels expected to peak Monday and Tuesday

The state has to meet a threshold of $1.6 million in damages statewide to receive Federal Emergency Management Agency funding, which the governor hinted at during the presser.

The state has up to 30 days to sign a disaster declaration, Noem said, and FEMA-authorized relief would cover 75% of the cost of damages, with the rest shared by the state and local contributors.

"We're thankful the storms are slowing down and that we're getting through this process," Noem said. "We're going to continue to remain engaged with all of our local governments."

Here's when water levels are expected to see their highest levels, per Noem:

• Big Sioux River: 7 a.m. Tuesday at 38.4 feet;

• James River: Sometime Monday or Tuesday at 25.1 feet;

• Vermillion River: Tuesday morning at 30 feet.

"That's really when we're gonna see the bulk of that water moving through the system, and we're working to be prepared for that," Noem said.

Rain totals in some cities for the last 72 hours have been "very significant," Noem said. Sioux Falls, Mitchell and Chamberlain have all seen more than 7 inches of rain, the governor said, while Canton received over 18 inches. At least 21 counties have been affected by the flood, she said.

"One of the biggest areas of concern," Noem described, resides at the southeastern tip of the state. Dakota Dunes, North Sioux City and Sioux City, Iowa, are under a particular threat, since the Missouri River runs adjacent to all three and are at lower elevation compared to upstream communities.

Noem is expected to hold her next press conference to give an update on flood conditions in the state at 2 p.m. Sunday in Dakota Dunes.

The declaration, an executive order, also includes an order for "no boating" on Lake Alvin in Lincoln County, Lake Henry in Bon Homme County, Marindahl Lake in Yankton County, Menno Lake in Hutchinson County and Swan Lake in Turner County.

More: Aging Lake Alvin spillway submerged by flood waters

As of Saturday morning, Lake Alvin had hit a major flood point. Significant rains, starting Thursday and continuing into late Friday night, filled the lake's spillway, a water control structure meant to control the release of water into Ninemile Creek, a tributary of the Big Sioux River.

When an Argus Leader reporter arrived 5 p.m. Thursday at the spillway's confluence with the creek along 480th Avenue in Lincoln County, the spillway was completely submerged with water. A nearby road leading to a fishing dock and vantage point by the lake was also under water.

Lakeside of the road, a visible whirlpool could be seen churning about 25 feet from the road, the reporter observed. Rushing water could be heard tumbling under the road and overflowing Ninemile Creek. Ditches along sections of the road were also partially flooded, but water had not risen above the street.

Noem said during the Saturday morning press conference the spillway's "entire watershed is being impacted by that, and those flows will continue to increase."

"Unfortunately, I think that situation, the water will go even higher," Noem said.

She added the spillway "still looks to be in good shape, even with that kind of water pressure."

The spillway at Lake Alvin, a 105-acre reservoir owned by South Dakota Game, Fish and Parks, is slated for complete replacement after flooding in 2019 damaged the aging structural integrity of the dam system's infrastructure.

This article originally appeared on Sioux Falls Argus Leader: Gov. Noem issues emergency declaration after eastern SD floods