Published October 05, 2009, 12:00 AM

Xcel Energy taps Minnesota River dam for removal

GRANITE FALLS — A dam built for one of the state’s first hydroelectric facilities is being considered for removal.

By: Tom Cherveny, West Central Tribune

GRANITE FALLS — A dam built for one of the state’s first hydroelectric facilities is being considered for removal.

Xcel Energy hosted an informational meeting Thursday in Granite Falls to outline its evaluation process for the Minnesota Falls dam, located about three miles south of Granite Falls on the Minnesota River. Constructed in 1905, the nearly 600-foot-wide dam housed a hydroelectric facility that operated until 1961. The dam also provided a reservoir of cooling water for a Northern States Power coal-fired power plant built upstream in the 1930s.

The dam no longer serves any purpose for the company, according to Jim Bodensteiner, senior environmental analyst and scientist with Xcel Energy. He said the Minnesota Department of Natural Resources has expressed concerns about the structural integrity of the concrete dam and ordered the company to begin evaluating either removing or improving the structure.

The dam is more likely to slowly crumble away in pieces rather than collapse in any sort of catastrophic way, according to Thomas MacDonald, P.E. water resources engineer with Barr Engineering.

Bringing the dam up to modern safety codes could cost as much as $4 million, according to MacDonald. He said it may cost as much as $1 million to remove it.

He said an earlier analysis looking at the possibility of restoring hydroelectric production at the dam showed it to be economically unfeasible. He said the hydroelectric capacity at the dam would be limited due to environmental requirements.

There is interest in seeing the dam removed by anglers and recreational users of the river. The dam serves as a barrier to fish migration. It prevents sturgeon, flathead catfish and even eels from migrating upstream, according to Chris Domeier with the Minnesota DNR fisheries office in Ortonville.

The stretch of river between the dam and Granite Falls has a poor game fishery because of the dam’s presence, he said.

Xcel Energy has not used its Minnesota Valley plant since 2004, according to Tim Brown, Xcel Energy plant manager for it and the Angus Anson plant in Sioux Falls, S.D. Brown said the Minnesota Falls plant is also fired by natural gas, and could be revived as a power plant without the need for the water reservoir provided by the dam.

At this point, Brown said the future of the idled Minnesota Falls plant is undecided, but it may be retired.

The dam’s affect on river water elevations are of concern to two upstream users. David Reimer, owner of the nine-hole, Granite Run Golf Course, said he relies on access to the river to fill holding ponds for irrigating the course. He said he needed more than 9 million gallons of water to irrigate the course this year.

“If I don’t have the water I don’t have a golf course,’’ he told MacDonald during the open house.

The engineer said that the course would continue to have access to the river were the dam to be removed.

The Granite Falls Energy ethanol plant also has a water intake above the Minnesota Falls dam and a permit from the Minnesota DNR to appropriate river water. The permit is based on river flow volumes.

MacDonald said there is a possibility that the ethanol company’s intake would need to be modified if the dam were removed, but he said that the dam’s removal would not affect the company’s appropriation permit.

Bodensteiner said Xcel Energy will develop a concept plan for the dam by the end of this year. It will hold additional public meetings to describe the plan. It must also wade through a series of regulatory issues and agencies. Consequently, he said it is not likely that any final decision will be made until late 2010, or early 2011.

The options for the company range from removing the dam entirely to leaving portions intact or repairing the entire structure.

The dam has been opened to draw down the river this autumn to evaluate how the water levels would be affected by it possible removal, and to see where the river’s natural channel is.

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