A center median on Wycliff Avenue at the Dallas North Tollway, complete with curbs and grass, is two weeks from completion.
An NTTA task force identified the area as at-risk for potential wrong-way crashes.
A small vacant lot is all that separates Brown Street and the Dallas North Tollway. Engineers say they were concerned that drivers on Wycliff Avenue turning left onto northbound Brown Street could mistakenly drive onto the tollway's southbound exit ramp.
The new median will be a physical deterrent to making such a turn. Engineers said the median will be high enough and wide enough that the impact of hitting it should be great enough to startle even an impaired driver.
Six wrong-way crashes have occurred on the Dallas North Tollway since 2007, killing four people.
The most recent crash was in June 2009. All of the wrecks involved drunken drivers.
Since the summer of 2009, NTTA has spent thousands of dollars on flashing signs and road markings that warn drivers from heading onto the tollway in the wrong direction.
The tollway authority is also seeking approval to use some newer, highly reflective signs that are only 2 feet to 2.5 feet tall.
The NTTA said its research shows that impaired drivers tend to look downward, behind the wheel for clues to where they are on the roadway. The agency said it hopes that the shorter signs will be more visible to such drivers and that the reflective material will catch their headlights -- and the drivers' attention -- faster.