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

Gov. Kristi Noem held a virtual 7 a.m. press conference Saturday to provide an update on flood conditions across the area.

Noem, joined by Mayor Paul TenHaken, Secretary of Public Safety Bob Perry and other emergency response professionals, said state and city authorities are preparing for regional water systems in eastern and southeastern South Dakota to see their highest water loads over the next several days.

Noem said 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: Sioux Falls asks residents to conserve water as flooding strains city wastewater system

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 impacted by the floods, 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.

The capacity at Lewis and Clark Lake "is not necessarily there to hold much more," Noem said, and the Niobrara River, as well as parts of Iowa and Nebraska in general, are already experiencing significant water intake.

To combat flooding there, Noem said she has been having conversations with the U.S. Army Corp of Engineers Omaha District about adjusting capacity levels at dams along the Missouri River.

"In response to the rainfall, which has exceeded 600% of normal over the past 24 hours, we will lower releases Friday at Fort Randall and Gavins Point dams," said John Remus, chief of the Missouri River Basin Water Management Division, in a press release. "While the decreased releases are expected to bring lower downstream river stages, they cannot offset all the flooding in the Sioux City area."

Noem is asking USACE to lower releases even further to slow water intake. Those additional restrictions make for a complicated affair, however; the dams aid power generation, and shutting down outflow could impact other parts of the country during the summer heat, Noem said.

"If we don't slow down some of this water that's coming into the system., we're gonna see the Dakota Dunes and North Sioux City potentially impacted and homes potentially impacted and we'd like to avoid that if we can."

The governor has not declared a state of emergency as of Saturday morning. 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."

Bob Perry, state Department of Public Safety secretary, said parts of Interstate 29 and other roads have been closed. He urged people that need to travel to check South Dakota Department of Transportation 511 website for road conditions and closures.

Sioux Falls wastewater system under the "most strain the system has ever had," mayor says

In Sioux Falls, the state's largest city, Mayor Paul TenHaken said the 38-foot water levels in the Big Sioux River will likely be a new record.

He asked for residents to limit water usage as the city's wastewater system undergoes the "most strain the system has ever had."

"We have thousands of people depending on this system," TenHaken said. "We need people to limit their wastewater use right now, and that means limiting doing loads of laundry. If you can avoid a shower today, that will be great. If you can avoid anything that puts capacity or strain on the system, it will be an incredible benefit to what we're seeing right now."

As an offset to severe flooding, TenHaken said the city has started diverting wastewater to several detention holding ponds.

However, those containers are "already at capacity," he added.

"The next 24 to 48 hours are going to be really kind of touch and go on what we're going to do with that capacity," TenHaken said. "Our No. 1 priority, of course, is to protect property."

TenHaken said the city has had to rescue six people caught in the flood so far. He urged people to stay away from Falls Park as the Big Sioux River reaches the crest of its water levels.

"One gentleman, I can't believe he didn't pass from being in the river near the falls," TenHaken added. "I would just say just maybe avoid going to the falls would be appreciated. It's not really a safe place right now."

More: Live updates: 'Life threatening' flash flood warning extended for Lincoln, Minnehaha

The Governor posted a short update on X, formerly Twitter, at about 1:30 p.m. Friday, saying she had visited several of the areas soaked by heavy rain Thursday night. She offered tips for homeowners, and mentioned how state officials were working with county officials.

"Be safe," she said. "Take care of your neighbors."

This article originally appeared on Sioux Falls Argus Leader: Gov. Kristi Noem provides update on South Dakota flood situation