The announcement came a day after Gov. Rendell repeated his request that the legislature raise $472 million to cover a shortfall in transportation funds. Officials said the project would not be affected by that, since funds for the work had been set aside earlier.
Brimmeier said obstacles to the project - concerns about noise and storm-water runoff - had been largely resolved. He said all rights-of-way and permits were obtained, and he predicted a completion date in fall 2012.
State Sen. Andrew E. Dinniman (D., Chester) said improving access to the Route 202 corridor was critical to helping Chester County retain and increase jobs.
He said the county recently learned that the pharmaceutical company Sanofi-Aventis - and its 500 jobs - was moving to New Jersey. He said several states had been aggressively lobbying for local businesses to relocate, touting better transportation systems.
Dinniman said he and other politicians and business leaders testified about the project's importance at a July 28 Senate hearing. He said the Turnpike Commission responded "within days."
More than 50,000 vehicles a day use the 14-mile stretch of turnpike between Downingtown and Valley Forge, Brimmeier said, with a projected 150,000 vehicles by 2025.
"You can see that we had to do something," he said, adding that safety and convenience will be improved.
Chairwoman Carol Aichele of the Chester County commissioners said the project was welcome news for the roughly 130,000 employees of businesses within a seven-mile radius of the new interchange.
Representatives from three business parks - Trammell Crow's Atwater Business Park, O'Neill Property Group's Uptown Worthington, and Liberty Property Trust's Great Valley Corporate Center - also praised the initiative.
Stephen G. Foster of the O'Neill Properties Group said adding the turnpike access could reduce the typical commute by up to 30 minutes.
"This will unlock the potential of Uptown Worthington," Foster said.
Dinniman said he opposed the project initially because it dumped motorists onto rural roads in Charlestown Township, but that hurdle was overcome when Trammell Crow donated 91/2 acres for ramps, limiting the impact on Route 29.
The project was part of $523 million in transportation funds earmarked to ease congestion in the area, Dinniman said. In December, PennDot is scheduled to open bids on widening a 4.2-mile stretch of Route 202 in Tredyffrin Township, he said. In addition, the turnpike is finalizing plans to widen six miles in Tredyffrin from two to three lanes, he said.
Dinniman said: "We are scoring big in Chester County."
Contact staff writer Kathleen Brady Shea at 610-696-3815