Army Corps flood managers draw big crowd in Pierre

Last week’s blizzard across the Dakotas and Iowa and Minnesota put 15 inches to 30 inches on the ground in most places and it’s melting now.

The soil, though, is more thawed and can absorb much of the new water dropped across the plains last week, Grode said. The problem with the similar-sized blizzard in mid-March was that the ground was frozen and mostly covered with snow and ice, so most of the rain and snow ended up running into rivers, many of them emptying into the Missouri, Grode said.

The Army Corps is forecasting a total runoff this year — from mountain snowpack, the plains snowpack and spring/summer rains — of 38.2 MAF, which would be the sixth highest over the past 120 years, Grode said.

“Compared to last year, in 2018, that was 42 MAF, the third highest,” he said. “We have had a very wet couple of years, (in terms of run off), the last two years.”

But the mountain snowpack is near average this year, not at 140 percent of average as it was in 2018, Grode said. Some parts of the Missouri River Basin have been wetter than normal so far this year, other parts are drier than normal, he said.

Sen. Mike Rounds, R-SD., was at the meeting in Pierre, his hometown. He’s on Easter break from the Senate. He told Grode and John Remus, head of the flood management division of the Army Corps in Omaha, that what most people in Pierre and Fort Pierre are concerned about is that they are not surprised by high releases of water from Oahe Dam which can pose problems for homes downstream near the river.

Others in the crowd echoed the same thought.

Fort Pierre Mayor Gloria Hanson implored the Army Corps engineers to provide more and quicker information about how much water will be released from Oahe Dam.

“We rely on the Army Corps of Engineers for our quality of life,” Hanson said.

After the meeting, Rounds told the Capital Journal he also is pressing the Army Corps to find money in its budget to put into place the new system the Corps has itself been planning , since 2011, to better monitor soil moisture and snow pack conditions on the plains of the Dakotas and Montana. It was a wet year in 2011, when a huge rain event — 8 to 9 inches over a big part of the Missouri Basin in a few days — led to the devastating floods that summer, including in Pierre and Fort Pierre.

The new monitoring system is being tested at SDSU in Brookings and the Army Corps needs to get it in place across the Basin’s prairies sooner not later, Rounds said Monday.

Remus reminded Rounds and others who asked if the Army Corps is ready for another big rain event like 2011.

“If we get another 2011, we are going to have 2011,” Remus said bluntly, “The system isn’t built to handle that (kind of rain event.)”

But right now, Remus and Grode said the forecasts look good and they are more confident this week than last that the mainstem dams on the Missouri will be able to handle the well-above-normal runoff from the plains.