While construction of a new entryway bridge still has at least four years to go, Del Mar has begun gathering input from the community about the new fixture.
City staff updated residents and fielded questions Jan. 10 on the Camino Del Mar Bridge Replacement Project.
The original bridge was built in 1932, widened in 1953 and modified in 2001. Its service life was originally supposed to be 50 years, but it has actually been in operation for more than 80 years, said Tim Thiele, city engineer.
The city has been studying a rebuild of the bridge since 2011 with Caltrans. In 2012, that study identified corrosion, seismic instability and poor hydraulics. As a result, a total replacement of the bridge was recommended as the most cost-effective solution.
City staff said the new bridge will adhere to current engineering and seismic standards and will be able to withstand 50- or 100-year floods. It would have a service life of at least 75 years.
Plans call for an eight-foot sidewalk, six-foot bike lane and 12-foot vehicle lane on either side of the roadway, with a seven-foot median in-between. The bridge would be supported by six piers. Currently, the bridge has 10 piers.
City staff said the change in the number of piers would reduce the footprint on the nearby wetlands and improve the hydrology of the river.
The new bridge also will be a little higher with a thinner deck than the existing one, leaving more room for water to flow underneath during high tides and when the river rises with storm run-off.
Early estimates place the construction cost between $25 million and $28 million, of which about 90 percent will be paid for through a federal grant. The city estimates construction could take at least two years.
The Del Mar City Council awarded a $1.2 million contract in early 2017 to Kleinfelder Inc. to begin engineering and environmental studies for the new bridge on Camino del Mar, as the 101 is known in Del Mar.
So far, the city has come up with two options for rebuilding the fixture: casting the concrete in-place or pre-casting the concrete elsewhere first, said Don Bloodworth, a civil engineer with Kleinfelder.
Additionally, the city has proposed two options for the rebuild process, he said. It could take place in stages, with one lane of traffic in both directions. Pedestrians would be routed to a temporary trestle, and construction could take between 24 and 27 months. Alternatively, the city could close the entire bridge for the rebuild, which would take 13 to 15 months.
Either way, an estimated 120 parking spaces could be temporarily lost for the duration of construction, Bloodworth said. Thiele added the parking spots would be closed in stages.
The city has also proposed three designs: Beach bungalow, which would adorn the bridge with sea animal designs and have an outlook area; Historical origins, which would feature a cobblestone-like design; and Modern-day, which focuses on the surrounding geographical features such as the fair, race track and Torrey Pines Reserve. This option would have an outlook area with seating in the shape of the City of Del Mar.
One resident asked how utilities would be accessed for servicing on the bridge. Thiele said the city could work directly with the utility companies and place the utilities within the cells of the bridge.
Another resident asked how emergency response times would be affected for those living on the northern end of the city, adding that she believed the city was gridlocked during the Del Mar Fair. Additionally, Don Mosier, former Del Mar mayor and current fairboard member, asked if the timeline for the bridge would conflict with the construction of the proposed Del Mar Resort and a railroad project on the bluffs by SANDAG.
Thiele said due to the city still being in the early stages of the project, the answers to those questions were still being studied.
He said the city is planning more workshops throughout the course of the project.
The city is also welcoming comments and questions to be submitted to Mohsen Maali, the deputy public works director, by emailing firstname.lastname@example.org or calling 858-755-3294.