Corps invites comments on operation of coulee structure

GRAND FORKS — The U.S. Army Corps of Engineers is seeking public input on its proposed operating plan for the Tolna Coulee Advance Measures control structure being built in Nelson County.

The document will be used by the project’s non-federal sponsor, the North Dakota State Water Commission, to operate the structure.

The approximately $9 million control structure is expected to be completed in March. The federal government is paying $5.5 million, while the state is paying about $3.5 million.

The operating plan rules originally were described in the project’s Environmental Assessment, which was released Sept. 2.

‘Catastrophic’ overflow

“The continued rise of Devils Lake has increased the potential for a catastrophic overflow of Devils Lake through Tolna Coulee,” the corps said in a statement Friday. “There is about an 8-percent chance that the lake could reach elevation 1,458 in 2012.”

If a large inflow to the lake occurred with the lake at 1,458 feet above sea level, significant erosion could occur at Tolna Coulee resulting in major flows, according to the corps. With erosion, the estimated maximum outflow would be 14,000 cubic feet per second, and the outflow would be above 12,000 cubic feet per second for 19 consecutive days.

“Flows of this magnitude would result in catastrophic flooding in Valley City, North Dakota (roughly equivalent to a 500-year flood), and other downstream communities,” the corps said.

While preparing the operating plan to prevent a catastrophic flood, the Corps determined it needed to modify it to account for the potential lake level fluctuations prior to overtopping the high points in the coulee, the corps said in its statement Friday.

The corps’ environmental review of the modification determined it to be minor and have no discernible environmental effects. Therefore, the Environmental Assessment and “Finding of No Significant Impact” remain valid.

Public input

The operating plan and environmental review document may be viewed and downloaded from the corps’ website at http://www.mvp.usace.army.mil/fl_damage_reduct/default.asp?pageid=1779.

The corps is requesting public input on the plan, specifically with regard to the implementation of the operating plan rules described in the Environmental Assessment.

Deadline for comments is Jan. 31.

The corps said it needs comments prior to placing the structure in operation in the spring. The request for comments pertains to the proposed operating plan only. Comments pertaining to other matters will not be considered or receive responses, according to the corps.

Comments may be sent to Steven Clark or Bill Csajko or at the Corps of Engineers at steven.j.clark@usace.army.mil or william.l.csajko@usace.army.mil, or to either at 180 E. Fifth St., Suite. 700, St. Paul, MN 55101-1678.

For more information, contact the Corps’ project manager Bill Csajko at 651-290-5853 or Steven Clark at 651-290-5278.

Kevin Bonham is a reporter at the Grand Forks Herald, which is owned by Forum Communications Co.

Tags: devils lake, news, flood