Quote of the Week: Grids vs Arterials

Overall, a gridded street network of two-lane roadways can accommodate both pedestrians in addition to much higher volumes of vehicles as compared to the large arterial/collector single intersection.  The superiority in capacity even holds when the grid system is compared against the arterial/collector without any pedestrian  accommodations whatsoever.  This research presented results in terms of vehicle delay and vehicle level of service; while not ideal in terms of truly understanding the impact of these large intersections in a complete urban environment, these results should instead be used to clarify many of the misconceptions that conventional traffic engineers have with regard to such large arterials/collectors intersections.   
Additional benefits of the grid system include real-time route decisions, increased levels of walking and biking, reduced vehicle speeds, and  as some recent research is showing, safer roadways for all users.  Critics may point out that the grid system increases overall vehicle delays for through traffic.  The analysis done as part of this study agrees with this assertion; however, the analysis is limited in that it assumes all trips begin outside the grid, travel through the grid, and then exit the grid.

From Supersized Intersections vs Gridded Street Networks: Comparing Capacities & Pedestrian Accommodation

Each week we feature a quote or an excerpt that clearly illustrates the benefits of new urbanist thought.