Carnegie Mellon University

aerial image of Pittsburgh and surrounding areas along route 51

Route 51 Corridor Transformation Study: Phase II

The Highway Corridor Transformation Study was an 18-month, two-part investigation that led to proposing new state highway corridor design guidelines for use throughout Pennsylvania. This holistic urban design, environmental and transportation research project included: adaptive traffic signalization; economic development and land use; stormwater management, environmental quality, and aesthetics; transit-oriented development, complete streets, and traffic calming; and multi-municipal civic engagement. A 13.5-mile length of Route 51 in Pittsburgh’s South Hills that involved four Pittsburgh neighborhoods and six municipalities from the Liberty Tunnels to Large, Pa. served as the research case study.

Phase 1 modeled adaptive signalization for Route 51 to determine flow benefits on this heavily-trafficked corridor (a 25%+ overall flow improvement) and documented existing conditions for holistic design use in Phase II. The 12-month Phase II investigation of corridor typologies, risk management and process issues, economic and environmental impact of each corridor type, and traffic-calming strategies resulted in the 2016 report, “Corridor Guidelines,” for PennDOT. It recommended a new Corridor Typology and highway corridor design recommendations to supplement PennDOT’s current Roadway Typology. The Guidelines identified seven corridor types and proposed smart transportation, multimodal, and right-of-way design recommendations that incorporated economic, environmental, and detailed design measures for guiding future highway corridor improvement projects. Additionally, the Route 51 case study provided valuable information for Route 51 improvements to coincide with a $9 million stormwater and sewer study and implementation plan by Economic Development South that was funded by the Pittsburgh Water and Sewer Authority. Carnegie Mellon’s Deliberative Democracy program partnered with RCI to conduct civic engagement research for working across multimunicipal boundaries for improving community decision-making involving highway corridor projects; the program’s findings were featured in a panel discussion during the fall 2016 meeting of the National League of Cities Conference in Pittsburgh.

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City of Pittsburgh

Pittsburgh Water and Sewer Authority

Economic Development South


Allegheny County

Southwestern Pennsylvania Commission


Donald K. Carter (PI)
Director, Remaking Cities Institute, Carnegie Mellon University

Stephen Quick
Adjunct Professor and Project Director, School of Architecture and Remaking Cities Institute, Carnegie Mellon University

Christine Mondor
Adjunct Faculty, School of Architecture, Carnegie Mellon University

Patricia Folan
Adjunct Faculty, Heinz College, Carnegie Mellon University

Stephen Smith
Research Professor, Robotics Institute, Carnegie Mellon University

Greg Barlow
Project Scientist, Robotics Institute, Carnegie Mellon University