Two parcels of land along the scenic St. Croix River soon will be permanently protected against development.

In St. Croix County, Wis., 53 wooded acres overlooking the river will compensate for bluffland lost in construction of a new four-lane bridge, which will span the St. Croix just south of Stillwater.

On the Washington County side of the river, 38 acres in Scandia will become the new Crystal Spring Scientific and Natural Area pending completion of the sale.

“Land acquisition is the most sure way to preserve the wild and scenic character of the river,” said Melanie Kleiss Boerger, chairwoman of the St. Croix River Association. “Right now with the development pressure, the rising population, the improving economy and the new bridge, it becomes even more important to get those parcels of land protected indefinitely.”

The St. Croix County land, in the town of St. Joseph, was purchased in early August when the County Board voted 17-1 to pay $746,000 from a $2 million environmental fund set aside to help guard against damage inflicted on the river by the new interstate bridge, which had been planned to open in 2016 but that has been pushed back.

The land has been owned by C.A. Richards, a judge, and his wife Jeanette. One county supervisor, Jill Berke, described it as a “legacy piece of land” and another, Agnes Ring, said it was one of the last remaining parcels that would allow county residents access to the river.

The county intends to work with neighboring landowners to slow erosion of the bluffs, said County Planner Ellen Denzer. In the 1930s, she said, a ravine collapsed and created a large beach on the river.

“It’s an awfully hard hike. It’s a real huffer and puffer,” she said recently. “This is a very steep, challenging location.”

Negotiations leading to the $675 million bridge project, decades in the making, included specific protections for the river. Much of the money available for environmental work went to St. Croix County as leaders plan for population growth and try to balance construction with conservation.

In Washington County, meanwhile, the Trust for Public Land (TPL) is negotiating to buy private property along the river that includes hardwood forests, rocky cliffs, a stream and a waterfall. The land won’t open to the public until the deal closes sometime this fall.

Bob McGillivray the TPL’s senior project manager, said it was too early to disclose the purchase price, but said the landowner “is a very conservation-minded individual who very much wants to see this land protected.”

The Washington County Board recently approved the establishment of the Crystal Spring area, but didn’t contribute any money toward the purchase. Once the TPL closes on the deal, the land will be turned over to the Minnesota Department of Natural Resources to manage its “rare features,” which include native habitat for plants and birds.

“It’s a major migratory corridor for many of our songbirds,” McGillivray said.

Washington County has four other scientific and natural areas, all of which the DNR manages.

McGillivray’s presentation to the County Board, shared with scientific and natural area specialist Larissa Mottl of the DNR — who said “it’s an extremely high-quality site in terms of its natural resources and biodiversity” — drew compliments from commissioners.

“Thank you for preserving this land,” Commissioner Gary Kriesel told them. “It’s outstanding.”