Improved transportation conditions for the Monongahela River Valley (Mon Valley) have long been a goal of the Commonwealth of Pennsylvania.

 Initial expressway planning in the 1960s was to serve the Mon Valley's world-ranked industries of steel, coal and coke production. With the economic decline of the Mon Valley in the late 1970s and 1980s, the planning efforts were refocused with the intent that better highway access and mobility would help redevelopment efforts in the area. PA Act 61 of 1985 and Act 26 of 1991 elevated the priority of developing the Mon/Fayette Expressway and Southern Beltway Projects, respectively.

The Pennsylvania Turnpike Commission (PTC) followed environmental and planning regulations established under the 1969 National Environmental Policy Act (NEPA), Section 404 of the Federal Clean Water Act, and other federal and state lawas in developing the Mon/Fayette Expressway and Southern Beltway Projects. These regulations mandate that major transportation projects be developed in an environmentally sensitive manner that addresses input from the public and environmental resource agencies. As a result, a full range of alternatives (including no-build, transit, roadway upgrades and new highways) were considered for these projects. Environmental clearances (Records of Decision) have been obtained for all seven Mon/Fayette Expressway and Southern Beltway Projects.

Completion of the Mon/Fayette Expressway and Southern Beltway Projects will create about 98 miles of new limited-access highways south and west of Pittsburgh in Allegheny, Washington and Fayette Counties.