All schematics are preliminary except as noted.
The turnpike's final 5-mile segment is generating most of the extra cost, says Mark Bouma, the authority's director of engineering. Agency officials opted to increase the roadway from four to six lanes, with 8-lane bridges, he says. But meeting tougher environmental rules are the most costly, says Bouma. There is also lead contamination requiring remediation. The extensive environmental permitting required for the last of the turnpike's four segments has delayed final design.