Placing physical barriers at some intersections can manage vehicle volume by diverting motorized traffic, while allowing other modes to filter through. This prevents motorists from using residential areas as shortcuts and encourages continuous access in the cycle network.
The most common filtered permeability elements are diverters and refuge islands. These can be created with permanent materials or interim elements such as concrete barriers or planters, or concrete elements built into the roadbed. Short contraflow cycle lanes on one-way streets may also be used to filter vehicle traffic. Filtering strategies may also calm vehicle speeds and enhance the safety of the cycling network.