Published October 17th, 2018
New Canyon Bridge design and construction update
By Vera Kochan
Image provided
Impressive plans for the construction of the new Canyon Bridge were revealed to the Moraga Town Council during its Oct. 10 meeting. Heading up the presentation were Edric Kwan, Moraga's public works director, Shawn Knapp, the town's senior civil engineer, and Jack Walker, lead design engineer from NV5.
The old bridge, built in 1936, was already scheduled to be replaced due to a biannual Caltrans inspection. In 2013, the town was awarded a $3.2 million grant from the Highway Bridge Program (HBP).
In 2014, Caltrans authorized phases that included preliminary studies, environmental impact, right-of-way and preliminary engineering. That same year, public works held its first community meeting covering issues such as speeding, funding, environment and pedestrian/cyclist access.
A second public outreach meeting was held in 2015, with revised bridge designs conforming to Moraga residents' suggestions, concerns and expectations. The new plans addressed speeding and pedestrian/cyclist access and safety, as well as sight visibility and bridge lighting.
Partial project study submittals to Caltrans began in 2016. Included were national environmental studies, a noise technical memo, air quality conformance, visual technical memo, a traffic study and bridge type selection.
In 2017, with the new bridge design and construction on schedule to begin in 2018, a landslide occurred adjacent to the bridge. In April of that year, the town closed the damaged bridge to all traffic and quickly scrambled to install a temporary one-lane, signal controlled bridge by mid-November.
The new bridge will be approximately 55 feet longer and two feet wider with retaining walls for added stability. Made of concrete, steel and pilings it will also be repositioned slightly south of the old bridge location. In 2019, the first phase will begin as the new northbound lane and approach is constructed, while traffic continues to use the temporary bridge. In 2020, construction for the southbound lane and removal of the temporary bridge begins, while traffic in both directions takes place on the new northbound lane.
Key design elements included from public input are bike lanes, multi-use paths, lighting, improved sight distance, aesthetics and safer guardrails.
With all of these new design factors, the town requested a $7.2 million budget. A major setback to the project was a 2018 funding freeze by HBP. The intrepid team at public works appealed the freeze, sighting the urgency of the situation, and Caltrans released the funds, approving a new budget of $6.5 million. The $700,000 funding shortfall is still to be addressed. The public works team is requesting that Caltrans provide the funding during the fiscal years of 2018-19, because funding for the temporary bridge lease expires in September 2019. At this point, the town would have to pay the $12,000 monthly rental fee.
Caltrans has set Nov. 1 as the deadline to accelerate funds and provide any due documentation. These documents include environmental, right-of-way and utility clearances. A final design is also required.
The construction of the new Canyon Bridge is scheduled to start in January when the town begins to advertise for construction crews. Opening bids will be accepted in February, and in March the town council will review and award the bid. The actual construction process will begin in April. All of this hinges on the 2018-19 Caltrans funding acceleration. If that fails, the town will have to re-evaluate its options.






Reach the reporter at:

back
Copyright Lamorinda Weekly, Moraga CA