For the first time in nearly three decades, a popular Southwestern Ontario retreat will again accept overnight camping starting next year. Inverhuron Provincial Park will open 125 camping sites, following a $2.2-million facelift set to start this spring.

"There was a huge demand for camping in this park when it closed in 1975," park superintendent Chris Tomsett said.

"And the population growth since then has been tremendous."

The new overnight camping sites at the Lake Huron park will open following the nine-month construction project, with a second phase -- depending on funding -- calling for another 125 camping sites.

"Inverhuron was one of the most popular parks in Southwestern Ontario," Tomsett said. "We're expecting very high occupancy rates. We've already had a number of people inquiring."

Inverhuron, near the Bruce Nuclear Power Development, opened for camping in 1956 with 351 campsites.

But when a heavy water plant -- which housed hydrogen sulphide -- at the nuclear complex was opened, Ontario Hydro bought the park from the province because of safety concerns if the potentially deadly sulphide escaped.

In 1973, that same year, Ontario Hydro signed a long-term lease with the ministry to allow it to operate the area as a day park. Overnight camping ended in 1976 and all the equipment -- an amphitheatre, exhibit centre and office buildings -- were removed.

The heavy water plant was shut down in 1998, rekindling potential for overnight camping.

While plans have been in the works since 2000, Tomsett said two requests for a full environmental assessment delayed the project. The Environment Ministry declined those requests Dec. 23.

That gave the final green light to the park expansion.

It's the first such expansion for Ontario Parks since Bronte Creek Park in Oakville added sites in 2002, Tomsett said.

Inverhuron is what's called a "historical class" provincial park, which means emphasis on protecting historical and cultural resources.

The area's pre-park history dates back 3,000 years, acting as home to both pioneer and aboriginal communities.

The park boasts a one-kilometre sandy beach -- part of its draw for campers, Tomsett said. The new campsites will be a short walk from the beach.

The plans subdivide the park into four areas -- historical, natural, development and nature reserve, with campsites confined to the development zone. There's also a buffer zone on the northwest portion of Holmes Bay, next to the nuclear station. The plan calls for a new reception centre, improved boat launch, new roads, comfort stations and campsites.