Minnesota DNR officials worried about flood diversion
FARGO -- Minnesota officials on Thursday raised concerns about the ability of fish to pass through a Red River diversion, underscoring that cost alone won't determine whether a Fargo-Moorhead flood control project sinks or swims.
The U.S. Army Corps of Engineers hosted about 30 local, federal and state officials from Minnesota and North Dakota at the Fargo Civic Center to gather input on environmental issues related to diversions and levees.
Bob Merritt, a Minnesota Department of Natural Resources hydrologist in Detroit Lakes, criticized the corps for "trotting out" its flood options to the public last week before taking a hard look at the environmental impacts.
He said the public has already made up its mind about the best option after a corps' analysis found a Minnesota diversion the most cost-effective plan.
"To be on the fast track as you are, and to suggest that there is only one alternative at this point, is very premature," Merritt said. "And to expect us to come up with the design for you that is going to mitigate the lawsuits is expecting too much."
Aaron Snyder, the corps' project manager, stressed that three viable options are still on the table - and the public is making clear which one it prefers.
Since last week's unveiling, the corps has received 500 to 1,000 public comments, almost all in favor of a North Dakota diversion, Snyder said.
"There definitely appears to be a political push, a local push and a local desire to have a North Dakota diversion," he said.
Luther Aadland, a DNR river ecologist, said a "big red flag" for him is the diversion control structure that would regulate river flow through the metro.
The DNR has worked for years with the corps and others to restore fish habitat and passage in the Red River, and the control structure "doesn't look like a workable design for fish passage," Aadland said.
"It's imperative that whatever project happens doesn't undermine everything that's been gained," he said.
The North Dakota Game and Fish Department also sent the corps a letter asking it to maintain natural river discharges and to provide for fish movement, Snyder said.
The concrete control structure would span the river channel and feature two tiers of culverts: The bottom tier would always be open, allowing the river to flow through. The top tier could be closed during floods, forcing a portion of the flow to spill over a weir into the diversion channel.
Aadland asked corps officials why a control structure is needed, noting the Otter Tail River naturally spills into the diversion at Breckenridge.
Snyder said a control structure would boost the diversion's reliability and better control the flow of water through the metro area. Without it, the head of the diversion channel would need to be larger.
Also, without a control structure, Snyder said a diversion had a cost-benefit ratio of .64 or .65 - not nearly high enough to qualify for federal funding.
"Basically, without it, we don't have a project. With it, we do," he said.
Five of the six Minnesota diversion options meet or exceed the corps' cost-benefit ratio of 1.0 to qualify for federal funding.
Two of the three North Dakota options have ratios of .95 and .94, but Snyder said it's possible they could hit 1.0 after benefits to transportation and West Fargo are factored in.
The North Dakota diversions carry cost estimates of $1.337 billion and
$1.363 billion - about $375 million to $400 million more than the cheapest Minnesota diversion. That's mainly because additional structures estimated at
$50 million to $60 million each would be needed where the channel would cross five tributaries, Snyder said.
A $902 million levee option also meets the ratio, but the corps says it would require removing 756 structures in Fargo and 397 in Moorhead, which local officials have said likely isn't politically feasible. Levees also would protect only to a 100-year flood level, compared to up to a 500-year level with a diversion, Snyder noted.
Snyder said a Minnesota diversion will probably emerge as the corps' National Economic Development (NED) Plan - essentially, the plan that gives the federal government the most bang for its buck.
A North Dakota diversion still could be the NED plan, "but the likelihood is fairly minimal, and we want to make sure that we're not misleading the public," he said.
Local officials may choose a different plan that meets the cost-benefit ratio, but it would need approval from the Assistance Secretary of the Army for Civil Works, which isn't guaranteed, Snyder said. Federal funds available would be capped at the NED plan amount.