The existing Dumbarton Rail Bridge
will see revived rail service within a few years. A new bridge for
high speed rail would replace it if the Altamont Alignment is chosen.
Building a new railway bridge at Dumbarton will be much easier
than building the new East Span of the Bay Bridge. Let's look at the
vital statistics of the two bridges:
East Span Bay Bridge
* does not include bike/pedestrian path (15’)
New Dumbarton Rail Bridge
Results of the
The columns for the East Span of the Bay Bridge are over twice the girth of what would be needed for a Dumbarton HSR bridge. The Bay Bridge goes from sea level to over twice as high as the Dumbarton, but not back to sea level. The difference in volume of the columns is almost 1500%.
The difference in the width of the two bridges is almost 500%.
Considering its mass, structural components, and construction challenges, the Bay Bridge East Span project is eight to ten times greater than a Dumbarton HSR bridge.
Using the Caltrans Construction Cost Index and escalating the Caltrans’ 1984 construction cost for the Dumbarton highway bridge ($70m), the 2003 cost would be around $119m.
The recently completed trestle for the San Mateo Bridge is over three times longer than the Dumbarton, yet a much simpler structure. In 1999, the winning bid for the project was only $113m.