Connected streets are needed to support mixed-use, study reports
Nearly all local land-use comprehensive plans nowadays call for mixed-use and walkability, but they often lack specific instructions on streets to enable those outcomes. A study in the Journal of Geotechnical and Transportation Engineering claims that well-connected street networks—e.g., street grids—are necessary to allow for mixed-use, compact development, and direct, short routes to destinations, which result in less automobile traffic, pollution, consumption, and crashes, and greater health and well-being.
Two scenarios were modeled in the study Interconnected Street Networks Result in Mixed-Use: A Key to Alleviating Auto Traffic. These scenarios were interconnected and hierarchical street networks. "The former can accommodate mixed-use effectively, and the latter cannot," explains the abstract "The result revealed significantly lower auto traffic, vehicle miles, and hours of travel in the grided roadway network. Reducing traffic is synonymous with making origins close to destinations which is made possible by grided roadways and mixed-use."
The study, authored by Hamid Iravani, concludes that the hierarchical network has more traffic, higher levels of congestion, higher vehicle miles of travel, and higher vehicle hours of travel. Performance measures were calculated to evaluate the connectivity and walkability of each scenario, indicating that the grid network has higher connectivity and is more walkable. Jurisdictions that seek mixed-use are advised to promote connected street networks.
This article addresses CNU’s Strategic Plan goal of working to change codes and regulations blocking walkable urbanism.