The state of Maryland has announced plans to build a bridge to replace the Francis Scott Key Bridge destroyed by a cargo ship a year ago. It is gratifying that plans to replace that vital span are moving along. Any new bridge will take years to put in place.
The proposed replacement bridge is to be a cable-stayed affair with a main span of at least 1600 feet. The main span of the former bridge was only about 1200 feet. Clearly, having a ship channel 400 feet wider would be a significant improvement. Whatever bridge is built, I assume its piers will be protected by substantial dolphins (no, not the marine mammals) and fenders.
After the Key Bridge fell, I suggested that a replacement bridge should be a suspension bridge. As fond as I am of cable-stayed bridges, both from an engineering and aesthetic point of view, a suspension bridge would allow an even wider channel for the ships of the next century. (Maryland wants a bridge with a 100-year lifespan.) A suspension bridge with a main span of 1600 feet would be considered short. In fact, a suspension bridge with towers on dry land would not be unreasonable. (Recall that the Golden Gate Bridge has a 4200-foot span, and newer bridges are being built with towers even farther apart.)
I suspect that cost was a major factor in the Maryland decision. I sincerely hope that the chosen alternative will prove to be an adequate one.
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