SR 322, Section 100 Corridor Improvements & Widening

Pennsylvania Department of Transportation | Delaware County, PA
state route roadway improvement project

SR 322 is an east/west principal arterial in the suburban Philadelphia region. The Section 100 corridor extends seven miles from just west of the I-95 interchange to the US 1 intersection. The roadway is locally known as Conchester Highway. This includes parts of three townships in Delaware County: Concord, Bethel, and Upper Chichester.

This portion has two typical sections, a two-lane section beginning at the US 1 intersection. The section widens into a four-lane divided highway. It extends past the Cherry Tree Road intersection to the eastern end of the project area. Meanwhile, nine major intersections are included, some of which are grade-separated.

Existing problems include traffic congestion, high accident rates, and uncontrolled access. However, the lack of adequate capacity to accommodate planned growth in the corridor and the existing geometry not meeting current design standards also played a role. Both the availability of “reserved” Pennsylvania Department of Transportation right-of-way to the south side of the roadway and the presence of development in the US 322 corridor allowed only widening improvements to be considered.

Benesch’s services included preliminary engineering studies, environmental studies, final design and construction consultation. The final design alternative for the US 322 corridor included the introduction of two additional lanes south of the existing roadway. The project also utilized a grassed median to control access to the US 322 corridor, along with left turn lanes and adaptive traffic signal systems to increase the capacity of existing intersections.

In addition, the project involved the design of three miles of non-motorized paths, five bridges, and eight culverts. This included sign structures, ITS devices, retaining walls and sound barriers. Lastly, the project will be built in three construction contracts (Sec. 101, 102 & 103) with a fourth contract (SR 3025/MIT) for construction of mitigation measures.