The relief road at Dauphin in south central Pennsylvania was designed to tackle serious traffic congestion in the area. The previous two-lane highway through Dauphin had long been recognised as a major traffic congestion bottleneck in south central Pennsylvania, particularly during rush hour and before and after football games on the road between Harrisburg and the state college.

THE DAUPHIN BYPASS SCHEME

The overall project was divided into two separate construction contracts. The initial $37.7m contract began at Route 443 and extended 3.2 miles to just beyond Hagy Lane in Middle Paxton Township, north of Dauphin Borough.

According to Baker Heavy & Highway (the main contractor) this involved more than five miles of highway, eight new bridges, upgrades to four existing bridges, construction of a combination box culvert/vehicular tunnel, 12 large retaining walls, noise walls, wetlands mitigation, construction of a PennDOT maintenance yard and salt storage facility and three park and ride facilities. The second contract extended 4.3 miles from the vicinity of Hagy Lane to near the Clarks Ferry Bridge.

“All four lanes of the road were opened for traffic in the last quarter of 2000.”

PROJECT TIMESCALE

Construction of the first section began in June 1998 and of the second section in August 1998. The majority of the work was completed by late 2000 with only minor work being left for completion in 2001. Delays (mainly related to the weather) to this schedule were minimal.

All four lanes of the road were opened for traffic in the last quarter of 2000, although there were some restrictions during the summer of 2001 to allow minor work on the pavements.

THE MAIN ROAD

The bypass project involved four lanes of concrete pavement (four miles of new four-lane highway and two miles of refurbished four lane highway), concrete shoulders, concrete median barrier, new interchanges with Routes 225 (directional interchange) and 325 (diamond interchange), and sound barriers to reduce noise impacts on adjacent residences in Dauphin Borough.

THE SERVICE ROAD

In addition to the main relief road, a continuous, parallel two-lane service road was included in the project. This was designed to enable local traffic to be separated from through traffic. In many areas, the ‘new’ service road occupies the same location as the existing Route 22/322 roadway.

TRAFFIC PROBLEMS AND SOLUTIONS

The inevitable disruption of the construction work led to measures to help commuters circumvent it. Four park and ride schemes were initiated in an effort to lessen congestion. In addition, the Pennsylvania Department of Transportation (PennDOT) also agreed to fund extra bus services.

The existence of the service road (constructed concurrently with the main bypass) also allowed fewer lane restrictions during the construction period than would otherwise have been the case.

LEAD CONTRACTORS AND COST

Baker Heavy & Highway, Inc. of Corapolis, Pennsylvania, was the general contractor for the first phase of the Dauphin project. The value of this contract was believed to be $37.7m. Baker Heavy & Highway were also given contracts for construction management in road projects in Pennsylvania subsequently.

The general contractor for the second section contract was Kinsley Construction, Inc. of York, Pennsylvania. The value of the second section contract was $44.3m.

“In many areas, the ‘new’ service road occupies the same location as the existing Route 22/322 roadway.”

Urban Engineers, Inc. were hired to provide construction management services for PennDOT.

A company called Johnson, Mirmiran and Thompson (JMT) was given a major role in the design of the projectenvironmental mitigation.

JMT was involved in the strategy and the design of a wetland project to mitigate for 3.5 acres of the Susquehanna river wetlands that were damaged or altered during the road construction.

JMT eventually designed a 4.5 acre site in York County with scrub, shrub and forested wetlands. JMT was awarded the ACEC of Pennsylvania Diamond award for engineering excellence for this project.