The piers of the old Batchellerville Bridge are being blasted to the bottom of Great Sacandaga Lake this week, starting the final stage of a four-year bridge replacement project.
Blasting started at midday Wednesday and is expected to continue through next week.
The demolition work follows the removal of the steel sections of the old bridge this summer, with work taking place just feet from the new bridge that opened to traffic last November.
The old bridge piers are being blasted into rubble that will sit at the bottom of Great Sacandaga Lake, where it is hoped fish will gather around them.
The old bridge, like its replacement span, stretched more than a half-mile across Great Sacandaga Lake and is the only physical link between the two halves of rural Edinburg that are separated by the man-made lake.
Electronic information signs at the bridge say the blasting will last through Oct. 4, but state Department of Transportation spokesman Bryan Viggiani said exact times of the work aren’t going to be publicized, to avoid drawing spectators, as the 2009 demolition of the Champlain Bridge did.
“The blast is going to be 90 to 95 percent underwater. We’re not talking the Champlain Bridge here,” Viggiani said.
He said blasts will be audible, but not much will be visible. The tops of the piers are covered with blasting mats.
“You’ll see a little bit of smoke, but not much other than that,” Viggiani said.
The new bridge will be closed to all traffic for five or 10 minutes at a time during the actual blasting, and Viggiani acknowledged that will lead to delays.
“Motorists should avoid the area if possible,” Viggiani said.
The Sacandaga region economy relies heavily on seasonal visitors and recreation, and the state intentionally waited until after the summer camp season to do the blasting.
The blasted piers will remain at the bottom of the lake, where the rubble has been approved by the Adirondack Park Agency to serve as “fish habitat.”
The current work is part of the state’s $46.7 million contract with Harrison & Burrowes Bridge Constructors of Glenmont to build the new bridge.
The new bridge is directly to the south of the old, which was built 83 years ago when the Sacandaga Valley was flooded as part of a Hudson River flood control project in 1930.
Edinburg town Supervisor Jean Raymond said some of the steel superstructure from the first bridge has been saved as a historic artifact and will be put on display at the town history museum.
The new bridge is taller than the old one, with an arched shape that allows sailboats to pass underneath. It also has a sidewalk — something the old bridge didn’t have.
Overall, the bridge replacement project is wrapping up a year ahead of schedule. Work began in the summer of 2010, with bridge completion scheduled for the fall of 2013 and old bridge removal in 2014.
The speed of the work was aided by an easy winter in 2011-12, but officials also acknowledged earlier that up to a year of extra time was built into the schedule in case the project faced delays due to severe weather or unexpected complications.
The project was 80 percent federally funded, with the remaining 20 percent coming from the state.
The new bridge is owned and maintained by Saratoga County.