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What about safety in the tunnel?

We are focused on assuring that the tunnel, when re-opened, is a safe place for people to travel. We envision the use of good lighting, motion-activated lights where needed, emergency phone call boxes, and video cameras linked to local emergency response authorities. We will work with police and other knowledgeable community officials and citizens to ensure that the tunnel will be equipped with systems that provide a safe and secure route.

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 bike and pedestrian use. That study concluded that the project would cost approximately $4.6 million. This estimate should be considered a rough ball park figure. We are currently researching to determine what the costs will be.

Where will the money come from?

We envision a number of sources of funds that will combine to make the 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 kind of tax approach to fund the tunnel. We all pay taxes already, and those funds should rightly be used for projects that the citizens of our communities support.

How long is the tunnel?

The Alto Tunnel is approximately 2,180 feet long — about 4/10s of a mile. It is approximately 12 feet wide and 16 feet high, and was built with a large redwood timber support structure.

Where is the Alto Tunnel?

The historic Alto Tunnel runs between Mill Valley and Corte Madera under the Alto Hill. One portal is easily accessible on the Corte Madera side near Chapman Road just south of the old town square, where the historic alignment of the Northwest Pacific Railroad runs. It is currently a dirt pathway extending south from the old town square. This portal is closed with large steel doors but has an obvious concrete portal structure with two date engraved at the top: 1884 when the tunnel was built, and 1956 when it was upgraded.

The Mill Valley side portal is more difficult to find, but is near the Edna Maquire School near Vasco Road. If you ride along the bike path, it turns to dirt near the school. If you were to follow this dirt path it becomes heavily vegetated; but the portal is there, in the hillside. It has been backfilled and simply looks like a pile of rock.

Will trains run through the tunnel again?

No. This project is only for use as a pedestrian/bicycling path. There are plans being discussed for the bringing a commuter rail service into southern Marin, but these plans involve railroad alignments to the north of the Alto Tunnel, and would terminate in Larkspur.

Who owns the tunnel?

The majority of the tunnel is currently owned by the County of Marin. Some small parcels are, we believe, still owned by the railroad, which is now the Union Pacific railroad company, located in Omaha, Nebraska.

What’s wrong with riding along the Highway 101 bike path, or up and over the hill?

Some point out that there are alternatives for cyclists to get between the towns. This is true, but the existing routes are either unsafe, or too challenging to be attractive to most people. The whole idea behind opening the tunnel is to provide options for the general public to travel between the towns, and have greater recreation options — to get those people who don’t walk or bike now to be encouraged to do so. Riding or walking along Camino Alto is not an option for children, the elderly, or frankly for those who would like to begin cycling or walking as transit but are discouraged by unsafe and difficult options.

Furthermore, the Alto Tunnel has been identified as a critical element in the County’s general plan for bicycle infrastructure. A contiguous, flat, separated bicycle "highway" concept is the goal, and much of it already exists. Re-opening the tunnel will fill a critical gap in realizing this vision.

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