Safe Routes Marin

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Last updated: Fri, Jan 14, 2000


1) What about safety in the tunnel?

We will work with police and other knowledgeable community officials and
citizens to ensure that the tunnel is equipped with systems that provide a
safe, secure route. With good lighting, motion-activated lights, emergency
phone call boxes, and video cameras linked to local emergency response
authorities, the re-opened tunnel can be a safe place for people to travel.
Studies show that bicycle paths and multi-use paths reduce crime and make
neighborhoods safer.

2) How much will it cost to re-open the tunnel?

One way to answer this question is to recognize that the project will never
be cheaper to do than right now! But we realize that this is a potentially
large capital project. A study was conducted in 1994 as part of the
North-South Bikeway Feasibility Study that made assumptions about the Alto
Tunnel and estimated the costs to excavate and re-open the tunnel for bicycle
and pedestrian use. That study concluded that the project would cost approximately
$4.6 million. This estimate should be considered a rough, ballpark
figure. We are researching what the costs will be.

3) Where will the money come from?

There are a number of funding sources that can be combined to make this
project a reality. State and Federal transportation funds are available
specifically for non-highway projects such as the Alto Tunnel. Private
fundraising will also be a part of the strategy, with appeals to foundations,
individuals, and businesses. We DO NOT propose any new tax to fund the
tunnel. The funds proposed come from taxes we already pay.

4) How long is the tunnel?

The Alto Tunnel is 2,180 feet long –about 4/10 of a mile. It is
approximately 12 feet wide and 16 feet high.

5) Where is the Alto Tunnel?

The Alto Tunnel runs between Mill Valley and Corte Madera under Alto Hill
along the historic alignment of the Northwestern Pacific Railroad. The Corte
Madera portal is easily accessible from the old town square, where a dirt
pathway extends south along Montecito Drive. The tunnel is closed with large
steel panels. Two embossed dates appear at the top of the concrete portal:
1884, when the tunnel was built, and 1956, when it was upgraded.

The Mill Valley portal is more difficult to find. It is near Edna Maguire School,
beyond the north end of the Mill Valley-Sausalito Bike Path. The path
turns to dirt beyond Vasco Court, then becomes heavily vegetated; but the
portal is there, in the hillside. It has been back-filled and simply looks
like a pile of rock.

6) Will trains run through the tunnel again?

No. This project is only for use as a bicyclist/pedestrian path.

There have been studies regarding commuter rail service from Sonoma County as
far south as the Larkspur ferry, though currently the southernmost terminal
being considered is San Rafael. If someday there is commuter rail service
through to Mill Valley and San Francisco it's unlikely that the Alto Tunnel
alignment would be the most effective route. And even if it were, a tunnel
might be bored regardless of whether or not there was an existing bike tunnel
in place. There is also the possibility that if a useful bikeway were already
established, a future rail line would be built elsewhere. In all likelihood a
bicyclist/pedestrian path through the Alto Tunnel would have zero effect on
whether or not rail is ever seen in the vicinity again.

7) Who owns the tunnel?

The majority of the tunnel is currently owned by the County of Marin.

8) What is wrong with riding over the Highway 101 bike path, or over Corte
Madera Grade?

The existing routes for bicyclists are unsafe, too long, and too challenging
to be attractive to many people. The whole idea behind opening the tunnel is
to provide the general public a sensible option for transit and recreation
beneficial to the entire community. The short, flat, and safe tunnel route
would be enjoyable and save time, making it conducive to increased walking
and bicycling for transportation. This would improve personal health for
users and improve environmental health for all.

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