In 1956, the first full year after the completion of the highway to Augusta, more than 3,808,382 vehicles used the road. In 2007, the Turnpike’s 60th year, total traffic on the Maine Turnpike had jumped to 63,387,400 vehicles (a 16-fold increase!). Traffic growth was particularly heavy during the late 1960s and early 1970s when, for several consecutive years, the Turnpike’s annual traffic volumes increased nearly 10 percent per year. As traffic volume increased, so did the interest to add more highway capacity to meet the traffic demands.
In 1971, Turnpike traffic reached the 10-million vehicle mark for the first time. In 1972, in order to handle projected growth, the Authority made plans to begin widening the Turnpike from four to six lanes from Kittery to Scarborough. The plan called for construction to occur over an eight-year project schedule.
Construction had barely begun on the first section, when the Maine Supreme Court ordered a halt to the project because of environmental concerns. The Court said the Maine Legislature would have to grant approval.