November 2023
Most regular commuters along Miller Ave are unaware of the bridge situated just west of Vogue Cleaners. This bridge serves as a passage for westbound motorists, cyclists, and pedestrians, allowing them to cross the Arroyo Corte Madera del Presidio creek. Earlier this year City Public Works staff discovered that certain sections of the bridge had deteriorated more significantly than initially noted during the City's Bridge and Culvert inspection program.
To prevent the need for closing the bridge to vehicular traffic, the Public Works team collaborated with consultants and regulators to carry out crucial emergency maintenance repairs. Just last month, they installed eight new steel I-beam assemblies, each weighing 1,000 pounds, underneath the bridge. These much-needed repairs are expected to extend the bridge's lifespan by several years.
At the project's outset, Public Works staff received an initial assessment indicating that the bridge was nearing the end of its expected service life. After a careful evaluation of the consultant's assessment and recommendations, staff devised a repair plan with a strong focus on worker safety and minimal disruption to the community and creek habitat.
Deputy Director of Public Works and City Engineer, Jared Barrilleaux, recognized an opportunity to enhance the bridge's load-bearing capacity by applying engineering principles. Operations Superintendent Mark Neumann further refined the design and coordinated collaboration with partner agencies such as the California Department of Fish and Wildlife, State Water Boards, NOAA National Marine Fisheries Service, and the Army Corps of Engineers.
In close consultation with the team, Mark decided to carry out this unexpected maintenance using in-house staff instead of hiring a contractor. This approach enabled the work crews to complete the repairs before the rainy season and resulted in significant time and cost savings. Streets and Sewer Supervisor, Jesus "Chuy" Beltran, played a crucial role in troubleshooting and fine-tuning the approach. Chuy, a dedicated department veteran with 21 years of experience, worked closely with lead maintenance workers Eismael "Mayo" Sandoval and Junni Lousang. Their collective experience, totaling over 65 years, played a pivotal role in refining and testing ideas.
Members from other maintenance divisions also pitched in, contributing to the project's success. Fleet Maintenance Division staff designed and crafted custom blocks to hoist the beams into place. Building Maintenance Worker Chris Kenney offered insights on constructing a temporary timber platform beneath the bridge, ensuring a safe working environment for the crew and protecting the creek. The project's biologist observed juvenile steelhead in the creek below, noting no detrimental effects related to the project.
The entire team approached the project with a commitment to ensure smooth and safe operations for the crew, the bridge, community members, the creek, and local wildlife. To ensure safety and protect the sensitive habitat, the crew underwent training and tested the lifting system at an off-site location before commencing work on-site. Following the initial controlled test, staff repeated the process at the bridge, closing the road to traffic after rush hour to field test the offloading of materials and the installation of a single beam. Lessons learned during this field test were reviewed during a debriefing session, improving safety and efficiency while enhancing the on-site work plan for the following week.
During the final stages, the team worked efficiently to position the new beam, thanks in part to the assistance of the City's Wastewater Treatment Plant maintenance team, who used their mechanic's crane for precise and rapid placement. Following the initial trial, an effective traffic control plan was implemented to minimize impacts on local businesses and residents. Employees like Roberto Alberto, a Parks Maintenance Worker with 30 years of experience, played a vital role in traffic control efforts.
In th
e end, the Public Works team takes great pride in its successful handling of this unique challenge, achieved through a collective effort spanning every branch of the Department of Public Works and beyond. The Public Works team is committed to ensuring the safety and maintenance of Mill Valley and deeply appreciates the understanding and cooperation of the community during necessary detours and disruptions.