Three Rivers Park District, which owns the Coon Rapids Dam on the Mississippi River, is seeking partners to build a hydroelectric plant that would generate power for more than 4,000 homes -- and revenue to help pay escalating dam maintenance costs.

The park district has attracted one proposal from a local company but would rather work with the four cities that have about 350 homeowners living along the 6-mile pool of water above the dam.

"Our preference is that the cities or state take over the dam. We would run the recreation," said Margie Walz, district associate superintendent. She said that suburban Hennepin County residents now carry the tax burden for dam maintenance and suggested that revenue from a plant might ease that burden.

But so far, the cities bordering the pool -- Coon Rapids, Anoka, Champlin and Brooklyn Park -- have shown little interest in going into the hydro business, said state Rep. Jerry Newton, DFL-Coon Rapids.

Newton said studies done for Three Rivers show that a hydro plant would cost about $30 million to build and would generate about 44 megawatts of power a year, enough to provide electricity for 4,421 homes. Through the sale of electricity to Xcel Energy, the plant would bring in $2.1 million a year at the high-water levels maintained in the pool during summer months. But from December to March, the level is now dropped 7 feet to reduce possible damage to upstream docks if an ice jam forms at the dam. The studies estimate the hydro plant could net $50 million in profit over 40 years if the building loan is paid off in 20 years.

One concern, Newton said, is that if a private company operated the plant, it could raise the winter levels to earn more income, but that risks damage to upstream property.

At this point, Three Rivers, which operates suburban Hennepin County parks, and Nelson Energy of Golden Valley have filed preliminary applications for a hydro permit with the Federal Energy Regulatory Commission. The permit process is expected to take about three years. Nelson Energy also has approached Three Rivers about operating a plant jointly.

Local reaction

On Monday evening in Anoka, City Council members and Anoka County Commissioner Dan Erhart listened to Newton's proposal for local control of a hydro plant. Erhart, of Coon Rapids, and several Anoka council members live along the Mississippi River pool.

Anoka City Council members indicated little interest in owning a plant but a lot of concern about possible ice damage.

"Our biggest concern is the water level in the winter," said Council Member Jeff Weaver. He said that the lower winter pool level gives riverfront property owners a cushion to prevent ice damage.

"This needs to be a partnership of communities on the river," Erhart said afterward. He said the county had no interest in owning the plant.

Brooklyn Park Mayor Steve Lampi said that owning a hydro plant didn't sound promising. "I haven't looked at the numbers, but that kind of investment is break-even at best," he said. However, if the plant is shown to be a money maker, a city partnership could work, he said.

Newton said he expects to seek funding in the upcoming legislative session for a study on how different winter pool levels would affect river owners' property.

The dam has undergone $11 million in major repairs since 1974, and Three Rivers paid $4 million of that, said Walz. The balance was paid by the state and a Metropolitan Council agency, she said. The dam had a hydroelectric plant from 1913 to 1966, after which Northern States Power removed it and gave the dam and adjoining land to the park district.

New permits required

The district currently has a permit from the state Department of Natural Resources (DNR) that sets winter and summer pool levels. A hydro plant would require a new permit that would set pool levels, said Kate Drewry, a DNR hydrologist for the north metro area. The DNR would consider factors that include potential effects on riparian landowners, the pool fishery and the river ecosystem, Drewry said.

Nelson Energy, which is also building a hydro plant at Lower St. Anthony Falls in Minneapolis, would like to work with Three Rivers, which has not approved the company's hydro proposal, said Doug Spaulding, a company manager.

He said whoever wins the federal permit gets the exclusive right to apply for a hydro plant operating license, which can take another five years to obtain. Spaulding said license conditions, including pool water level, would be set by the Federal Energy Regulatory Commission, which would listen to concerns of the DNR and others.

"We don't want to get into an adversarial situation with Three Rivers or landowners on the river," Spaulding said. "We are looking at an existing resource to find a way that makes sense to provide a benefit to everybody involved."

Jim Adams • 612-673-7658