"Now that we've seen the problems, let's look at how an effective Access Management plan can provide solutions. Here is our Diamond Interchange in its original configuration, and here is the way it might look AFTER Access Management is applied.

• On Interstate highways, the Missouri Department of Transportation guidelines call for a minimum two-mile interval between interchanges in urban areas, with a minimum of 5 miles in rural areas. This allows sufficient room for lane changes that occur when traffic is entering or leaving the interstate.
• Notice the greater distance between the interchange ramp terminals…and between the interchange and the first crossroad. MoDOT Access Management guidelines call for spacing of at least 700 feet between ramp terminals…750 feet between a ramp terminal and the first available right turn…and roughly one-quarter of a mile before the first available left turn. These distances give traffic a chance to clear the area immediately around the interchange and give turning vehicles more time to maneuver.
• Driveway entrances are consolidated to manage the number of right turns and raised medians are used to control the number of available left turns. These changes alone can decrease the accident rate on this road by as much as 50 percent."