For decades, drivers traveling north or south along Interstate 79 (I-79) in Cranberry Township, Pa., who wanted to head east or west on the Pennsylvania Turnpike (I-76) had to exit onto state roads and cross a busy intersection in a dense commercial area before getting on the highway. Since June 2004, however, drivers have been able to make the change from I-79 to I-76 without missing a beat. The Pennsylvania Department of Transportation (PennDOT) completed construction of the $44 million Cranberry Connector — a series of bridges, ramps and roads — last summer to directly connect the two highways, which had been separated by only a short distance since their construction many years ago.

Cranberry Township, which is located at the northern edge of the Pittsburgh metro area, has grown rapidly in the last 25 years, surging from 10,000 residents in 1980 to more than 25,000 in 2003. Coinciding with residential growth, the number of commercial and retail businesses increased, many of them locating along U.S. Route 19 and U.S. Route 228 near I-79 and I-76. Motorists and truck drivers who wanted to travel only between I-79 and I-76 had to use routes 19 or 228, both of which included several signalized intersections and were crowded with local traffic.

Leaders at PennDOT, the Pennsylvania Turnpike Commission (PTC), the Southwestern Pennsylvania Commission (SPC), Butler County and Cranberry Township recognized that traffic was becoming cumbersome on area roadways and envisioned building a direct link between I-79 and the turnpike that would eliminate traffic congestion on Routes 19 and 228 and allow vehicles to flow freely on the interstates. In 1989, PennDOT contracted with Pittsburgh-based Gannett Fleming to design preliminary plans for the new interchange.

Funding shortfalls delayed the project in the mid-1990s, but in 1997, PennDOT, PTC and the Federal Highway Administration devised a plan to use existing I-79 southbound lanes as the collector-distributor roadway and relocated the southbound through-lanes in the median. That configuration saved three miles of roadway reconstruction and limited access ramp reconstruction. It also minimized the need for right-of-way acquisition and trimmed $16 million off the project's budget.

The final project plan called for replacing the two, three-lane Route 228 bridges over I-79 with one, seven-lane bridge and building ramps from the bridge to the highway. Next, the 3,500-foot connection between I-79 and the turnpike would be built, and the southbound I-79 lanes would be relocated to the median. Nearly 15 miles of roadway and ramps, and three new bridges that carry the connector over the turnpike, I-79 and Route 19 would be constructed. A new three-lane bridge that carries Freeport Road over I-79 also would be built.

PennDOT contracted with Pittsburgh-based Dick Corp. to lead the construction. Work began in 1999, and all construction was completed in June 2004. The project was paid for with federal and state funding as well as money contributed by PTC.

To accommodate plans for the new bridges and ramps, PTC moved a toll plaza at I-76 and Route 19 to a nearly 40-mile-long stretch of the turnpike west of the Cranberry Connector. The $23 million Warrendale Toll Plaza opened in 2003 and features express lanes for flat-fare ticketless toll collection, which allows motorists to drive through the toll plaza at highway-speed and pay tolls electronically through windshield-mounted transponders.

The Cranberry Connector has reduced average daily traffic from 85,000 vehicles to 57,000 vehicles along Route 19 as well as cut truck traffic on local roads by 75 percent. Additionally, traffic volume at the Route 19/Route 228 intersection for vehicles traveling between I-79 and I-76 has decreased by 25 percent. Those accomplishments, along with the interagency coordination that was necessary to complete the connector construction, garnered the project recognition as a national finalist in the American Council of Engineering Companies 2005 Engineering Excellence Awards competition.