The steady tide of Montana counties joining the Big Sky Passenger Rail Authority increased to five this week, and several more are likely to join later this month.

Missoula County Commissioner Dave Strohmaier said both Park and Broadwater counties voted to adopt the resolution establishing the authority, which now has enough participants to become official.

“Broadwater County voted to adopt the joint resolution establishing the Big Sky Passenger Rail Authority,” Strohmaier said earlier this week. “As of about an hour go, I learned that Park County also adopted the resolution, bringing our county count up to five counties so far.”

Gallatin County was the first to adopt the resolution in late July, followed days later by Missoula County. Butte-Silver Bow County followed, as has Park and Broadwater.

Advocates are hoping the seven other Montana counties that have expressed interest in joining the rail authority will also adopt the resolution in the coming weeks. Strohmaier has said that other latecomers will be welcome to join.

Once established, the Big Sky Passenger Rail Authority will create the governance to investigate, seek and accept funding for passenger service. It will also work in concert with the state’s congressional delegation and transportation officials to implement inter-city rail service across Montana's southern tier.

It could also lead to rail service between Billings and Denver, and Butte and Salt Lake City, supporters have said.

“I’m super pleased with the breadth of representation we’ve gotten on that authority so far,” Strohmaier said.

Under state law, only two counties are needed to establish a rail authority. The Big Sky Passenger Rail Authority wold be the first of its kind in Montana. The Missoula City Council has also backed the resolution.

Amtrak ran the North Coast Hiawatha across Montana’s southern tier from 1971 to 1979. The route included Miles City, Billings, Livingston, Bozeman, Missoula and Paradise, among other communities.