How planners are chasing better traffic flow with design Construction Dive » State transportation departments and their design teams can reduce the level of congestion and better control traffic flow using one of a handful of interchange layouts. Interchanges use ramps and connectors to direct traffic from one freeway to another or to move traffic from the freeway onto local roads. Michelle2017-10-06T11:18:23-08:00October 5th, 2017|Roads, U.S. News, Urban|