Will there be any full closures of the bridge due to construction?
How will vehicles be impacted by construction?
How will bicycles and pedestrians be impacted by construction?
How will kayakers and other creek recreationalists be impacted by construction?
What are the hours of construction?
Will parking be impacted by construction?
What are the project costs, and where do the funds come from?
Why does it take four years to build this bridge?
Why are the traffic signals at both Magnolia and S. Eliseo so slow?
When is the second northbound lane on Magnolia north of Bon Air going to be re-opened?
There are three anticipated vehicular traffic closures of the bridge. All attempts will be made to maintain pedestrian and bike traffic at all times. Ongoing coordination with emergency services will ensure emergency vehicle traffic is adequately accommodated.
- One week or weekend closure for delivery and installation of precast girders in Phase I
- One week or weekend closure for delivery and installation of precast girders in Phase II
- One week or weekend closure for concrete pour between upstream and downstream halves of new bridge
A minimum of one month notice will be provided when these closures are scheduled.
Two strategic traffic shifts will be conducted so that phased construction can occur. First, vehicles will be moved to the downstream south side of the bridge so that the existing upstream north portion can be demolished and its replacement built. When the upstream south portion is complete, traffic will be shifted onto the completed bridge so that the existing downstream portion can be demolished and rebuilt. When the downstream half is complete, the bridge will reopen to full traffic.
There will be periodic one-way traffic control on the bridge. Delays of maximum 5 minutes are expected during these times. Every effort will be taken to minimize inconvenience to bridge users, including carefully orchestrated traffic management with on-site signage and flaggers.
The project team will ensure that motorists, bicyclists, and pedestrians continue to have safe access to the bridge throughout construction. The start of Phase I work will close the bike lane and walkway on the upstream side of the bridge. Bicycle and pedestrian traffic will be consolidated on the downstream side of the bridge.
There will be periodic pedestrian and bicycle traffic control for safety and utility requirements.
Traffic control will be managed on the waterway for safety. Waterway traffic will be monitored and controlled/restricted during most operations to provide for the safety of any waterway users.
Standard City construction hours are 7 a.m. to 6 p.m. weekdays and 9 a.m. to 5 p.m. on Saturdays. There will be portions of the work that need to occur outside of these windows such as foundation pier concrete pours that need to be continuous and cannot be completed in a 11 hour window. The City may also from time to time evaluate night or Sunday work to limit impacts on the public.
No, parking for construction workers will be provided in the temporary staging area on Bon Air Road.
The construction cost of this project is estimated at approximately $27 million. Approximately 89% of the funding will come from the federal Highway (HBRR) Program, administered through Caltrans. Utilities will pay for all utility relocations, and the balance will come from the City Bridge Fund.
The project is anticipated to take four years to complete based on the environmental conditions at the site and the desire to keep the bridge open to traffic during construction. There are federally and state protected species in the vicinity of the site, which limit permittable construction techniques and the time of year certain activities can take place. To keep traffic moving across Corte Madera Creek during construction, the bridge is being built in two halves. The combination of these conditions results in two years’ worth of construction being stretched out to four years.
The traffic signals, during this mid-construction phase, are not able to detect traffic and change timing as most other signals in the City are. The signals are operating on a fixed time schedule to accommodate the peak traffic flows.
Staff is working with the Contractor to determine the best phasing for completing the intersection work at Bon Air/ Magnolia and paving and opening up the second northbound through lane. In addition, staff is still working with the engineers and regulatory agencies for approvals on the revised Magnolia Avenue Storm Drain Enhancements project that will allow the lane to be paved and re-opened.