A Twin Cities engineering firm hired to design the demise of the Rapidan Dam expects it to disappear by the end of 2028 — 118 years after the structure was completed southwest of Mankato, Minn.

Barr Engineering was selected by the Blue Earth County Board last week to draft the complex plan for the removal of the 87-foot-high concrete dam. The historic structure, which once produced hydroelectric power but has been mainly a tourist attraction in recent years, was doomed by the extreme flooding that ripped away a bank of the Blue Earth River on the dam’s west side on June 24.

The Bloomington-based firm was awarded the $1.47 million contract after outperforming the only other applicant for the job — Dallas-headquartered AECOM — in every category of the county’s scoring process.

“Barr Engineering was the clear and present better proposal in staff’s opinion,” County Public Works Director Ryan Thilges told the board.

The firm’s plan is to complete preliminary designs and specs by the summer of 2026. Final designs will be drawn up in the third quarter of next year, and funding sources are expected to be fully identified by the end of the year. In early 2027, bids will be sought from contractors interested in demolition of the dam and reconstruction of the river.

“Abatement and removal of hazardous materials and equipment in the powerhouse” will follow in May and June of 2027, according to the schedule. Removal of the dam, which was built from 1908 to 1910, is to begin in July of 2027 and continue through the following year.

The Barr Engineering’s contract has the potential to grow to nearly $2.4 million if $911,000 in optional tasks are approved in the future by the County Board. Those added tasks could include handling the bidding process, overseeing the contractor’s work and planning park and trail amenities in the area.

After debating the future of the dam repeatedly in the past several decades and then having those decisions become more urgent following the June disaster, the County Board moved quickly to approve the contract to plan its departure.

“It’ll be nice to get rolling on that,” Chairman Kip Bruender said.

The expectation is that the cost of the engineering expenses will be covered by federal disaster funds, although work will continue for some time to get funding aligned for the hefty cost of the dam’s removal.

Preliminary estimates provided by Barr in August suggested the price tag could range from $59 million to $75 million, although more work is needed for a comprehensive estimate.

“FEMA has not fully approved, obviously, the reimbursement for the dam incident. We’re still working through that process,” Thilges told the board. “We do anticipate that this contract cost will be eligible for reimbursement with FEMA after everything is said and done.”

In addition to the dramatic damage to the dam site, the June flooding undermined the County Road 9 bridge across the Blue Earth River just upstream from the dam, and the board last week approved another engineering contract to design a replacement bridge.

TKDA of St. Paul won that $2.558 million contract in a close competition with SRF and Bolton and Menk, which came in just a hair lower in the county’s scoring system.

“We received three very good proposals,” Thilges said.

Emergency transportation funding from the state and federal governments is expected to cover the cost of the engineering and the new bridge. The deck of the old bridge had already been mostly removed last week by Hosier Worldwide of Deer River, which won the $1.16 million contract to dismantle the 1985 span.