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Citizenship Central: Submit Comments By October 11 On Alto Tunnel Rebuild

Those following the proposed Alto Tunnel Rebuild project ---surely the biggest issue to hit Marin in years---should know that the county is providing a chance to weigh in, pro or con. Comments will be accepted via mail and email through October 11.

Web address for comments to the project manager is Carey Lando also runs the website that is sponsored by the county. Find the full 50-page cost estimate report there under "Projects".

When commenting on the project, be sure to write “Alto Tunnel Rebuild Comments” in the subject line. Might be wise also to request an e-receipt for your comments.That way you can be sure they will be published and not slip through the cracks.

The county intends to publish citizen comments with answers from staff on its website by November. Be sure that your local decision makers, Councils of Corte Madera and Mill Valley, will be reading them. That’s because for the project to proceed along what was the old railroad right-of-way, the county needs to be granted permission from local jurisdictions on both sides of the tunnel.

Exercise of citizenship is of utmost importance here on this critical issue, affecting the future of community at so many levels. Please take the time to comment. You will feel rewarded inside, I’m sure, for doing so.

While you're at, you might want to copy these local decision makers on your email:

In Corte Madera:

Supervisor Dennis Rodoni,
Mayor Diane Furst,

In Milll Valley:
Supervisor Kate Sears,
Mayor Jessica Sloan,

.Though the county’s latest cost estimate of $46.8 to rebuild and reopen the tunnel for bicycle recreational use came in lower than the $60 million estimated back in 2010, those following the issue need to know that the $46.8 million does not include upgrading of approaches---the Scott Valley Multi-Use Path in Mill Valley and the Tunnel Lane Path on the Corte Madera side. Those upgrades could easily add another $8.7 million to the project.

And the cheaper $46.8 million estimate is, after all, a best case scenario.

The latest study shows that the tunnel is three-quarters filled with collapsed Franciscan Shale. No one knows exactly what engineers will find until they remove backfill within the reinforced southern portal and also bore out 125 feet of concrete plugging the north portal.

There is a big unanswered question in that first phase of work.

Will the 132-year-old timber supports installed by the Union Pacific Railroad still be functional? They had better be. The county makes that best case assumption in their $46.8 million plan to add a structural steel skeleton within the network of old timbers, shrinking the original bore’s size, and subsequently reinforcing tunnel walls with concrete.

John Palmer, vice president of the Scott Valley Homeowners Association, is a professional builder with years of big project management experience. He has written an excellent Marin Voice opinion piece published September 25 in the Independent Journal, titled “The Real Cost of Reopening The Alto Tunnel”. View it here at

But the discussion at the local level needs to about more than simply cost. Environmental impacts are just as important.

(NOTE: If you are a passionate tunnel supporter you'll want to stop reading right here---with a reminder to send in your pro-tunnel comments. But it you're a tunnel skeptic,as I am, please do read on.)

As a local living in Corte Madera not far from Old Town Square and Tunnel Lane, I intend to highlight some of those potential environmental impacts here. Forgive me if that list is extensive. But the issues I raise are surely worth considering. I am a 45-year resident of Corte Madera who has been following this highly controversial project for a very long time.

For starters, I do applaud the county’s study to evaluate the inner condition of the tunnel. But remote camera viewing through drill bore holes reveals that the Alto Tunnel, sealed at both portals since 1979, is already filled with collapsed Franciscan shale debris beneath the hill’s high crown. Given that fact, isn’t it reasonable to ask why the county suggests spending $8.5 million to further stabilize the tunnel against cave-ins should we decide to “abandon” it?

But here’s an even bigger question. Why don’t tunnel advocates point out that this supposed ADA accessible tunnel serving ages “eight to 80-plus” will be only 11.5 feet wide along its artificially-lit 2,172 foot length? And that there will be only two claustrophobia-inducing lanes, north and south, in which those on foot will have to compete for space with a mighty stream of cycling tourists?

That’s important because the county plans for between 850,000 and 1.85 million annual users, roughly equaling the 1.2 million visitation each year to Muir Woods. If even half of that unsettling forecast proves true---benefiting of course recreational cycling and local café owners---where does that leave the rest of us?

Should we ignore:

---A negatively altered soundscape affecting local residents in quiet neighborhoods on both sides of the tunnel when an exuberant spoked-wheel invasion rolls in.

---The county’s ill-advised plan to “take” residential property above tunnel entrances to facilitate re-boring, debris clearing and re-bracing---a mega project taking 2 ½ years.

---Future stalling of peak hour traffic at Mill Valley’s East Blithedale and Corte Madera’s Tamalpais Drive crosswalks when inevitably the paths and aims of cyclists and car commuters collide.

---The eventual takeover by a cyclist majority of what are quiet multi-use paths adjacent to the tunnel, now shared democratically by all user groups.

--Necessity of a redesign of Old Town Square in Corte Madera to accommodate the peleton passing through what is now the middle of two busy commuter parking lots.

---Possibility of mandatory rezoning of historic Old Town Square for high density development when regional planners decide that three square mile built-out Corte Madera should bear the burden of another “WinCup”-size housing allocation so locally housed cyclists can realize the MTC-ABAG Cycletopia Dream of “bike commuting” to San Francisco through a re-constructed Alto Tunnel.

---The fact that 1,100-foot Cal Park Tunnel rebuild, half as long but comparable in width at 11.4 feet, was pitched at costing $5 million but completed at a whopping $27 million, five times over budget.

---Annual maintenance costs pegged conservatively at $308,000---who pays, the county or local jurisdictions?

Surely these potential negative impacts deserve the most serious consideration from local decision makers. It is my sincere hope that they will that will look at all sides of the issue and not simply rubber stamp this project so clamored for by the fulltime lobbyists of the powerful Marin County Bicycle Coalition.

Mega projects such as the Alto Tunnel Rebuild should be evaluated on their own merits, with consideration of all facets affecting various stakeholder groups. Final decision making should not be given over to politics, for in that there is much danger. Politics can often be a very uneven playing field. In this case, residents of what are now tranquil neighborhoods on both sides of the tunnel can in no way compete with the powerful political machine that MCBC has built over the last 20 years---spending as much as $153,000 in lobbying in a single year, as declared on MCBC’s Schedule C Tax Return for 2012.

My own personal thought is that surely there has to be a better way, without a slew of environmental impacts, to boost the profile of cycling in Marin---which is after all an enviable goal.

The irony is that MCBC’s desired last link in the “North South Greenway” already exists, circumventing Mill Valley’s Horse Hill. Its overall length is about equal to the tunnel route between Mill Valley and Corte Madera. Upgrading and flattening Horse Hill’s two short climbs to an easy five per cent grade would cost a seventh of the rebuild of the Alto Tunnel. And taxpayers would not have to worry about picking up the tab in the event of an Alto Tunnel budget overrun. After all, the county’s estimate of $46.8 million does not include upgrading approaches to the tunnel. That $46.8 million estimate, cautions the county report, is only an “Opinion of Probable Costs”.


Alto Tunnel, Alto Tunnel Costs, Alto Tunnel Impacts