The owner of a $2.6 million mansion in Eden Prairie has been slapped with a nearly $25,000 fine after the city said he illegally cut down more than a dozen protected, towering trees in his back yard, which overlooks the scenic Minnesota River.

The fine is a rare step by the city — its largest-ever penalty for violating a conservation easement, which legally limits a landowner from making changes on a property that might threaten the environment.

In the settlement, approved last month by the city, the mansion’s owner, Mitchell Coopet, 39, agreed to pay the fine and replant 27 trees in his sprawling back yard.

Coopet’s tree-chopping is one of 12 violations the city has experienced in about 20 years of easements, with his fine being the largest.

“We take it very seriously,” City Manager Rick Getschow said.

During negotiations with the city, Coopet admitted that he had cut down 17 of the trees, but said the previous owner of the 13,048-square-foot house had cut down even more to make way for a back yard patio.

The settlement with Eden Prairie allowed Coopet to deny any liability for cutting down trees in the easement area. Coopet didn’t return a message from the Star Tribune. His lawyer, former Minnesota U.S. Attorney Tom Heffelfinger, declined to answer questions, saying, “We’re very pleased to settle this dispute quickly with the city.”

Over the years, as metro cities have set aside more land before developments close in, conservation easement violations have surfaced occasionally. Yet despite the rising amount of protected land in Minnesota, a statewide report of conservation easements released in February found few violations statewide.

The nonprofit Minnesota Land Trust has seen few violations while overseeing about 440 conservation easements statewide. Those few violations usually arose because a homeowner inadvertently affected easement land, said development director Walter Abramson.

“It really just draws attention to how important it is that the easement holder … gets out there and visits the property,” he said of the Eden Prairie case. “That keeps violations from happening in the first place.”

His group does annual inspections of every easement to make sure homeowners know and follow the rules. That kind of monitoring was among the recommendations included in the state legislative auditor’s report earlier this year, which said that state-funded easement holders need to closely monitor easements to ensure homeowners are complying.

The city of Eden Prairie first heard of Coopet’s case when a resident complained last year.

The exclusive Bell Oaks Estate neighborhood in which he lives is atop bluffs overlooking the Minnesota River, with many multimillion-dollar homes shaded by gigantic old oak and black walnut trees. Off Hwy. 169, a curvy, rural-like road leads up to the neighborhood, nestled in dozens of wooded acres and meadows that once were part of one large estate.

Coopet’s 1.5-acre lot hugs the bluffs next to the river. A real estate listing for the home boasted the river valley vistas from the mansion, which includes an indoor pool, basketball court and theater. It was listed in 2007 at $3.2 million, according to real estate sites, and sold for $2.6 million to Coopet, identified on several websites as an executive at a Minneapolis software company, Code 42.

In 1994, the city established the conservation easement along the bluff to protect the scenic land, restricting residents from removing or planting trees.

But last July, a neighbor complained to the city that a number of trees had been cut down on Coopet’s property. Getschow said the city responded to the complaint within a week. It found that 50 trees had been removed, in part to make room for a patio that never was approved through a building permit and that also cut into the conservation easement, according to city documents.

“This is one of the more significant disturbances,” Getschow said.

In the settlement, Coopet, who moved into the five-bedroom mansion in April 2012, claimed the previous homeowner cut down many trees and built the patio. According to the city, Coopet cut down 17 more trees, but in the settlement, which was approved by the City Council on May 21, he was able to deny claims that he was liable for any tree removal.

Coopet is required to plant 27 trees by Sept. 2. According to the settlement, they must be red oak, bur oak, honey locust, eastern red cedar, hybrid elm, bigtooth aspen, hackberry or black walnut trees. That will repair the amount of tree cover needed, Getschow said.

The $24,900 fine that Coopet pays will go into Eden Prairie’s park fund.

The incident shows that the city takes the land preservation agreement seriously, Getschow said. He encouraged residents to notify the city if they see similar violations.

Otherwise, he said, “we may never know about it.”