Fort Worth police have asked city council members to prohibit large trucks from driving in the left lane of I-30 in the downtown area. The prohibition would cover a 15-mile stretch of road.

"Studies have shown that keeping trucks from the left lane does provide a safer roadway. It cuts down on switching of traffic between trucks and cars,” said Jodi Hodges of the Texas Department of Transportation.

If the city council takes this action, it would be phased in gradually after a full-scale study by state officials. A pilot study already has shown a drop in accidents by almost 70 percent under a left-lane ban along the same road, state transportation officials said.

Public education about any ban would include warning signs and media campaigns followed by police enforcement about six months later.

Houston currently prohibits trucks in some left lanes and other Texas cities including Austin, Waco and El Paso are considering similar measures. Left lane prohibitions are increasing in other states, too. Maine authorities, for example, are considering a left-lane truck ban along I-95 citing pollution concerns rather than congestion for the prohibition.