For years, Keith Melton, Arlington's public works and transportation director, has watched drivers use the wide center left turn lanes on Cooper Street for almost everything but turning.

"They dive into it and they speed up, they slow down, they cross over. Pretty much everything except what it was intended for,' Melton said.

Those central Arlington drivers can expect a slow down and a change of habit later this year when the state begins installing new medians.

Raised brick medians, traffic safety devices currently being used in south Arlington, will be extended north in a move that city and state officials hope will decrease the number of dangerous collisions and the number of pedestrians being hit by cars.

The open center turning lanes that now run along Cooper Street north of Arkansas Lane will be filled in with the same medians in place between Arkansas Lane and the southern city limits. The new medians would be added between Arkansas Lane and Mitchell Street.

Melton said the area currently presents a particular challenge because those who live in apartments near State Highway 303 attempt to cross Cooper Street on foot with sometimes fatal results.

City leaders asked the Texas Department of Transportation to install the same medians that the agency put in place in 2007 to replace the two-way continuous left turn lane on Cooper Street from central to southern Arlington.

After that project, the Texas Transportation Institute performed a post-construction evaluation and found that safety had improved and crash rates were reduced by 47 percent from Arkansas Lane to Pleasant Ridge Road and by 42 percent from Bardin Road to the southern city limits.

TxDOT is expected to bid out the roughly $8 million project this fall. Spokesman Val Lopez noted that traffic studies have shown that raised medians reduce head-on collisions-the most dangerous kind- by about 40 percent.

Lopez said without the medians, it can be difficult for turning drivers to anticipate the oncoming traffic flow and for oncoming drivers to know when and where cars will turn in front of them.

"Medians create an orderly, more predictable traffic flow,' he said. "And predictable traffic is safer traffic.'

Melton said medians provide structure, which is especially important in areas like Cooper Street where speed and unpredictable driving patterns are common.

"There are way too many unexpected movements going on at once in that area,' he said.

The City of Arlington is contributing $1.5 million toward the cost of the construction of sidewalks and drive approaches.

In addition to the raised median project, TxDOT also will repair concrete pavement from Arkansas Lane to Interstate 20 and build new Americans with Disabilities Act-compliant sidewalks, ramps and driveways from Interstate 20 to Mitchell Street.