Bridge construction then and now
A couple days ago, a group of us were able to visit a bridge construction site near our headquarters. The site is on Route 4 near Enfield where the New Hampshire Department of Transportation is undertaking a project to replace a bridge that is estimated to carry about 17,000 cars and trucks over the Mascoma River every day.
This bridge was built in 1927 making it close to 90 years old. The years have definitely taken a toll. The photo on the left below shows what the bridge looks like from the underside. Three concrete piers—one on each side of the river bank and one in the middle—are all crumbling and the steel is pretty rusted.
Compare that with a photo (on the right) of the new bridge going up now. This bridge is a lot wider with several thick beams—cut with the help of Hypertherm plasma of course—and reinforcements. Also notice the solid concrete wall. Since the NHDOT estimates traffic over this bridge will nearly double to 29,000 cars a day in the next 15 years, that’s a good thing!