OLD LYME — In response to concerns from the maritime community concerning vertical waterway clearance, Amtrak has redesigned a portion of a new bridge that will replace the 1907 bascule bridge that extends across the Connecticut River between Old Saybrook and Old Lyme.
The vertical clearance underneath the existing bridge is about 17.75 between spans and close to 18 feet under the movable span, according to an email from Craig Rolwood, a rail practice project manager with Hardesty & Hanover LLC, which is a consultant to Amtrak.
The new bridge, an $400 million project expected to be completed in 2030, will increase vertical clearance by six feet, to 24 feet under the movable portion. However, all of the stationary spans will decrease in vertical clearance to heights ranging from 13.58 feet to 15.98 feet.
Rolwood said that local mariners, including Cy Libby of Safe Harbor Marina in Essex, pointed out that during the summer boating season, when use of the river is heavy, smaller vessels pass beneath the stationary spans.
In response, Amtrak investigated and found it could redesign span number 6, adjacent to the west of the moveable portion of the bridge, which will have a vertical clearance of 17.71 feet.
“The reason for the approach spans having a little less vertical clearance is that the present-day, efficient design uses modern deep girders under the bridge deck rather than much more expensive through-trusses from the 1907 vintage, existing bridge design,” wrote Rolwood in a Jan. 11 memo to the Amtrak Conn. River Bridge Project Design Team.
Steven Ross, vice chair of the Old Lyme Harbor Management Commission, said having a reliable, working bridge will keep traffic on the river moving, even if lower vertical clearances will result in a few more boats traveling under either span six or the movable span.
“It is not a major problem. I would prefer that this situation didn’t exist but I think that having a reliable bridge that will open and close when it should is a good offset,” he said. “There are times when I’ve seen the whole river shut down because they couldn’t move the bridge.