A new $3.9 million trailhead building for Cottage Grove Ravine Regional Park could get underway as soon as this week, if the Washington County Board approves costs that came in about 10% higher than expected.

Plans for the 4,000-square-foot building include a multipurpose great room, lobby, restrooms and a picnic shelter at the popular 515-acre park, located just north of Hwy. 10 on Keats Avenue in Cottage Grove. It would replace a dilapidated shelter built in 1985 that was closed to the public two years ago and torn down over the winter.

Projected construction costs came in at $2.9 million, about $300,000 above the county’s estimate. Add to that a 7% contingency on the project, and total unbudgeted costs amount to $462,300. The project’s total $3.9 million cost includes design, construction, furnishings and equipment.

In a presentation he plans to make at Tuesday’s board meeting, Wayne Sandberg, deputy director of the county’s Public Works Department, will propose paying for the project with $2.5 million in county bonds, $500,000 from the state and Metropolitan Council, and $933,000 from Legacy state sales tax funds.

Sandberg said that bids on the trailhead building project accurately reflect expected costs and the market even though they came in a bit high.

“We didn’t feel they were out of line,” he said.

If county officials choose to wait on construction, costs could climb even higher, Sandberg said. The building process, expected to take about a year, could get underway in the coming week if the board moves ahead, he said.

The new trailhead would sit to the north of the parking lot and playground on the east side of Ravine Lake. Renderings of the proposed building show a structure similar to the Nordic Center at Lake Elmo Park Reserve, with large windows looking out on the park and modern architectural details.

The trailhead building was included in Gov. Tim Walz’s bonding request to the Legislature, with $2 million in state funds pledged for the project. Sandberg said that if those funds are approved, the county will use them on further park improvements, including upgrading the fishing pier and playground and possibly adding lights to the trails.

The park saw a major improvement two years ago with the addition of a new entrance road off Keats Avenue. The county replaced a park entrance off E. Point Douglas Road, the frontage road for Hwy. 10, that wasn’t as visible, said Sandberg. It also regraded the park’s ravine area and expanded the park’s trails, which can be used year-round and are groomed for cross-country skiing in winter.