In June, 1995 Mike Worden, of Concrete Systems Inc., Hudson, N.H. bid on a project requiring a bridge over some wetlands in a new residential development in North Andover, Mass. The specification called for a 40-foot span, but Worden convinced the contractor to allow a 36-foot arch-box precast bridge unit. During the summer, the project was postponed, and the contractor replaced. By the time Worden was able to negotiate with the new contractor, new regulations were in effect that required a 40-foot span to cross the wetlands. Fortunately for Worden, CON/SPAN Bridge Systems, Dayton, Ohio, had recently developed a 42-foot span that Worden was able to produce in time for the winter construction project. Installation of the bridge went quickly, taking less than five hours to place all seven precast spans. Headwalls and wingwalls were installed the following day, the joints were sealed, and the bridge was backfilled and compacted.