This Contract was a major component of the Metrolink commuter rail line from downtown Los Angeles to Oceanside, California. Metrolink had been operating on the old Amtrak line until the time of these contracts. Our contract and other similar to it, added a second track on the existing right-of-way; including all the bridges, retaining walls, and other structures that were necessary to add a second track from Oceanside to Los Angeles. This enabled uninterrupted service in both direction, a requirement of an efficient commuter rail system.

Our Contract involved building four new bridges in the City of Anaheim. Two of these bridges were precast concrete spans with cast-in-place concrete substructures. The other two were steel plate girder spans with cast-in-place concrete substructures. The two pre-cast concrete span bridges were built next to the existing bridges, however, the two plate girder span bridges were double wide replacement bridges.

Of Course, rail traffic had to remain moving during construction, making the construction of the steel bridges very difficult to schedule. The longest steel bridge had an additional time constraint due to the fact it was over the Santa Ana River. Nationwide/Shimmick had only five months from start to finish for this bridge, because the US Army Corps of Engineers wanted everything out of the river before the winter rains.

The new concrete substructures for the steel span bridges had to be built beneath and around the existing bridges on temporary falsework. Once the substructure was finished, the steel spans, were assembled next to the existing bridge and then “rolled in” over a 48 hour shutdown period. Nationwide/Shimmick successfully demolished the two old bridges and rolled in a total of 5 plate girder spans (90’ ea) which made up the two bridges (1 - one span, 1 - four span), during the very brief weekend shutdown period, without disrupting the commuter rail traffic.