Cycling enthusiasts have long dreamed of reopening the rotting, 125-year-old Alto
Tunnel as a key link in a greenway stretching from the Golden Gate Bridge to
Cloverdale. Now they may get their chance, as the county’s Non-motorized
Transportation Pilot Program begins a $225,000 study of three routes between the two southern Marin towns.
The tunnel between Mill Valley and
Corte Madera is the focus of a transportation workshop tomorrow night in
The other two routes are well known to any cyclists who’ve
ridden north of Mill Valley: an existing bike path over Horse Hill by Highway
101 and the twisty Camino Alto, which climbs to about 450 feet on the hill above
the tunnel. Neither route is pedestrian-friendly, and many cyclists shy away
from Camino Alto because of its narrow lanes, fast cars and afternoon traffic
The 16-foot-wide tunnel would link existing bike paths on
both sides of the hill. Southern Pacific sealed the 2,172-foot passageway in
1971, dooming its 12-by-14 redwood supports to rot in the stagnant, moist
darkness. The southern entrance collapsed during a rainstorm in 1981 and several
other portions have been filled to protect the homes on the hilltop.
“People are very, very excited about the
tunnel," said Andy Peri, a spokesman for the Marin County Bike Coalition who predicted dozens of cyclists will show up.
"One woman just called me and told me she’s bringing all five of her
children from 7 to 17 years old.”
the tunnel won’t be easy. Neighborhood residents, who’ve enjoyed the solitude of
hiking along the overgrown approaches, are organizing against the project. “It
is a [public] right-of-way and it is not their private property, but a lot of
people would like to see it left alone. Some people have a fear that homeless
people would be living up there," said Peri.
Seidler, founder of the nonprofit Transportation Alternatives for Marin (TAM)
and a vocal advocate for the tunnel project, allows that "change is
difficult" for people. But he noted that studies by Rails to Trails
Conservancy (PDF) show the same local residents who oppose the reopening of tunnels often turn
out to be their biggest fans when the projects are completed.
even bigger obstacle may be the cost. The price tag on the shorter, wider Cal
Park tunnel between San Rafael and the Larkspur tunnel is already up to $22-24 million, according to Peri. Nobody knows what kind of shape the
Alto Tunnel is in, but the current guess is that renovation costs would be
comparable. The study is intended, in part, to develop a better estimate.
who is also president of Wilderness Trail Bikes,
says the tunnel project would be worthwhile even at a cost of more than $20
million because it would help to complete the greenway, which, in turn, connects
the communities that sprang up along the old rail lines during the 19th century.
"The essence of bicycle transportation is that, to
work to its potential, there needs to be a complete system," he said.
"The rail lines are the most direct and efficient paths of travel between
The workshop is Wednesday at 6:30 p.m. at Edna Maguire School, 80 Lomita Drive, in Mill Valley.