Complex intersections, especially those situated at neighborhood centers or at the junction of several major streets, have tremendous potential to fulfill latent demand for public space. Irregular intersections, which result from successive urban developments and alterations, often occur at the threshold between adjacent grids or where new or preexisting roads cut through the conventional neighborhood layout. Often overbuilt and confusing, these intersections present safety hazards to all users.
Traffic flow and multi-phase signals result in long delays for pedestrians and cyclists, while at the same time causing confusion among drivers. Acute angled intersections reduce visibility for motorists, while obtuse intersections allow for high-speed turns. Both acute- and obtuse-angled intersections create unnecessarily long pedestrian crossings. Redesign intersections as close to 90 degrees as possible, implementing turn restrictions and street reversals where applicable.
The following examples are all based on actual intersections.
Add island or square-off. Limit turning speed around obtuse angle, shorten crossings, separate vehicle flows.
Minimize footprint or create two mini-intersections. Mini-junctions need to be far enough apart to operate as two, or close enough to operate as one.
Square off and separate, or remove a leg. Some streets are ideal to serve as non-motorized routes.
Prioritize either grid or circle. Maintain view corridor.
Use curbs to manage drivers. Extend medians.
Clarify and simplify. Convert redundant streets into greenswards.
Organize and prioritize flows. Solution might be found in the network.
Adapted from the Urban Street Design Guide, published by Island Press.