 |
Results of Alto Tunnel Geotechnical Study and SMART Extension to Sausalito
Author: Loony Loon
Date: 01-16-2017 - 11:59
Sounds like there will be study results soon because the study is about to get underway. Anyone hear anything about a SMART extension to Sausalito?
[www.marinij.com]
A study to determine the cost and safety of a disputed proposal to reopen the Alto Tunnel will require engineers to drill into the Mill Valley and Corte Madera ends where homes sit atop the sealed old railroad passage.
The $558,620 study is the next step in determining whether the 132-year-old tunnel could be reconstructed into a multiuse path, improving accessibility for bicyclists and pedestrians between the city and town. Still, no decision has been made to reopen the tunnel, a project sought by bicyclists who say it’s a key connector in the North-South Greenway — a network from the Golden Gate Bridge to Novato.
Crews will begin work on the eight-week investigative study on Jan. 30, marking the first inside look into the tunnel in the 35 years since it has been sealed.
“This is a geotechnical investigation to observe the interior of the tunnel,” said Bob Goralka, principal civil engineer at the county public works department. “It’s to help us better identify the scope of improvement that would be required to reopen the tunnel and update the previous cost estimate,” which was between $40 million to $60 million.
The plan is for crews to drill five holes, 4 inches in diameter, at two sites to probe the tunnel with laser scanning poles used to map it. Crews are expected to work for three weeks at 35 Underhill Road and another five weeks at the intersection of Chapman Drive and Camino Alto.
Neighbors and concerned residents could learn about the study at an informational meeting at 6:30 p.m. Jan. 18 at the Corte Madera Community Center at 498 Tamalpais Drive.
After a 2015 study that assessed the tunnel’s right of way, a handful of homeowners who could be affected by the project felt their property rights were threatened.
That included Liz Muller, who lives above the Corte Madera end. At this point she has no opinion whether the tunnel should be reconstructed, but she has a few concerns about the process.
“What I want to understand is the safety of my home and my property rights,” she said.
The county public works department held a separate meeting this past Thursday night to which Muller and residents of 25 other properties above and contiguous to the tunnel were invited.
Muller appreciated the opportunity to have more time to discuss how the studies and any project moving forward would affect her property directly.
Advertisement
Corte Madera Mayor Diane Furst, who shares concerns about the structural safety of the tunnel, said she plans on attending the Wednesday meeting.
“This study will provide us a lot of good information about the condition of the tunnel and what might be needed,” she said.
Mill Valley Mayor Jessica Sloan said, “Over the years, the city has not taken a stance on the project, but (city officials) look forward to reviewing the findings of the study, gathering Mill Valley community input, and participating in the discussions on the issue.”
The Marin Bicycle Coalition is happy to see the county move forward with this study, said Bjorn Gripenburg, the coalition’s policy and planning director.
“It’s really the last major information gathering hurdle to clear in order to discover what it would take to reopen the tunnel,” he said.
But those plans have caused consternation for some neighbors to the tunnel who fear it would draw constant noisy bicycle traffic to the area.
“I don’t want a bicycle freeway through my backyard,” said John Palmer, a longtime opponent to the plan who lives in the Scott Valley neighborhood in Mill Valley.
Despite his disapproval of that plan, Palmer is supportive of the study.
“You can’t deny the county the information they need,” he said. “They’ve come up with a relatively unintrusive way to do the work.”
A report of the study is expected to be available for public review this summer.
For updates, go to walkbikemarin.org/projects_alto.php.
[www.marinij.com]
A study to determine the cost and safety of a disputed proposal to reopen the Alto Tunnel will require engineers to drill into the Mill Valley and Corte Madera ends where homes sit atop the sealed old railroad passage.
The $558,620 study is the next step in determining whether the 132-year-old tunnel could be reconstructed into a multiuse path, improving accessibility for bicyclists and pedestrians between the city and town. Still, no decision has been made to reopen the tunnel, a project sought by bicyclists who say it’s a key connector in the North-South Greenway — a network from the Golden Gate Bridge to Novato.
Crews will begin work on the eight-week investigative study on Jan. 30, marking the first inside look into the tunnel in the 35 years since it has been sealed.
“This is a geotechnical investigation to observe the interior of the tunnel,” said Bob Goralka, principal civil engineer at the county public works department. “It’s to help us better identify the scope of improvement that would be required to reopen the tunnel and update the previous cost estimate,” which was between $40 million to $60 million.
The plan is for crews to drill five holes, 4 inches in diameter, at two sites to probe the tunnel with laser scanning poles used to map it. Crews are expected to work for three weeks at 35 Underhill Road and another five weeks at the intersection of Chapman Drive and Camino Alto.
Neighbors and concerned residents could learn about the study at an informational meeting at 6:30 p.m. Jan. 18 at the Corte Madera Community Center at 498 Tamalpais Drive.
After a 2015 study that assessed the tunnel’s right of way, a handful of homeowners who could be affected by the project felt their property rights were threatened.
That included Liz Muller, who lives above the Corte Madera end. At this point she has no opinion whether the tunnel should be reconstructed, but she has a few concerns about the process.
“What I want to understand is the safety of my home and my property rights,” she said.
The county public works department held a separate meeting this past Thursday night to which Muller and residents of 25 other properties above and contiguous to the tunnel were invited.
Muller appreciated the opportunity to have more time to discuss how the studies and any project moving forward would affect her property directly.
Advertisement
Corte Madera Mayor Diane Furst, who shares concerns about the structural safety of the tunnel, said she plans on attending the Wednesday meeting.
“This study will provide us a lot of good information about the condition of the tunnel and what might be needed,” she said.
Mill Valley Mayor Jessica Sloan said, “Over the years, the city has not taken a stance on the project, but (city officials) look forward to reviewing the findings of the study, gathering Mill Valley community input, and participating in the discussions on the issue.”
The Marin Bicycle Coalition is happy to see the county move forward with this study, said Bjorn Gripenburg, the coalition’s policy and planning director.
“It’s really the last major information gathering hurdle to clear in order to discover what it would take to reopen the tunnel,” he said.
But those plans have caused consternation for some neighbors to the tunnel who fear it would draw constant noisy bicycle traffic to the area.
“I don’t want a bicycle freeway through my backyard,” said John Palmer, a longtime opponent to the plan who lives in the Scott Valley neighborhood in Mill Valley.
Despite his disapproval of that plan, Palmer is supportive of the study.
“You can’t deny the county the information they need,” he said. “They’ve come up with a relatively unintrusive way to do the work.”
A report of the study is expected to be available for public review this summer.
For updates, go to walkbikemarin.org/projects_alto.php.
Results of Alto Tunnel Geotechnical Study and SMART Extension to Sausalito