Cyclists Turn Attention to Alto Tunnel

Julia's first trip through the Cal Park Hill Tunnel recently was also one of her first bicycle rides. She had a little trouble staying upright, but that didn't erase the smile on her face.

The numbers are still coming in, but the newly-opened path from Larkspur to San Rafael seems to be a hit with a lot of cyclists in the area. Finally, they have a way to cross between the cities without worrying about cars.

"People are seeing what can be constructed in Marin. The Cal Park Tunnel is a state-of-the-art project," said Kim Baenisch, executive director of the Marin County Bicycle Coalition. "People are discovering it's more enjoyable to walk or ride on these routes. As we expand the bike network, there are more opportunities to choose to bicycle."

Other opportunities could be waiting in the wings after this recent success. The push to reopen Alto Tunnel remains on the coalition's long-term agenda.

The half-mile Alto Tunnel was built in 1884 by the Northwestern Pacific Railroad and connected Corte Madera and Mill Valley until it was sealed in 1971. Cyclists riding from Corte Madera can challenge steep and winding Camino Alto or take the Horse Hill bike route that follows part of Highway 101 to reach Mill Valley.

"It's a good workout," said Peter Ryan after a ride over Camino Alto. "It gets a little wild. You certainly have to watch out for cars. I don't know about the tunnel, but it sounds interesting."

Marin County is one of four test communities under the Non-Motorized Transportation Pilot Program, which is designed to show the effects of increased walking and cycling on personal health and air pollution. The county receives $25 million over a four-year period through the program.

The Marin County Board of Supervisors examined a study in September that suggested 1.85 million people annually would use the Alto Tunnel. A preliminary price tag for the project was estimated at $40-50 million.

"There's a huge constituency that wants to open the Alto Tunnel. We fill the board meetings whenever we have discussions about that," Supervisor Steve Kinsey said. "I think we all believe it would be a good investment. But is it the right time? Is it a priority?"

Reopening the tunnel would likely require significant work, considering a partial collapse in 1981, which was quickly stabilized. There are also questions about the bike traffic and the structural stability from property owners who live on the hill.

"The homeowners are a force that need to be respected and their needs have to be addressed," Kinsey said.