Kansas

Missouri, Kansas join other states pushing 'zipper merge'

  • Drivers head north on U.S. 69 into a construction zone in Overland Park, Kan., Thursday, July 7, 2016. Kansas and Missouri departments of transportation hope to manage heavy construction seasons by persuading polite midwesterners to do the zipper merge. Rather than merging as soon as it's safe, drivers will be asked to wait to merge as long as possible after reaching the construction zone for repairs. (AP Photo/Orlin Wagner)

    Drivers head north on U.S. 69 into a construction zone in Overland Park, Kan., Thursday, July 7, 2016. Kansas and Missouri departments of transportation hope to manage heavy construction seasons by persuading polite midwesterners to do the zipper merge. Rather than merging as soon as it's safe, drivers will be asked to wait to merge as long as possible after reaching the construction zone for repairs. (AP Photo/Orlin Wagner)  (The Associated Press)

  • Drivers head north on U.S. 69 into a construction zone in Overland Park, Kan., Thursday, July 7, 2016. Kansas and Missouri departments of transportation hope to manage heavy construction seasons by persuading polite midwesterners to do the zipper merge. Rather than merging as soon as it's safe, drivers will be asked to wait to merge as long as possible after reaching the construction zone for repairs. (AP Photo/Orlin Wagner)

    Drivers head north on U.S. 69 into a construction zone in Overland Park, Kan., Thursday, July 7, 2016. Kansas and Missouri departments of transportation hope to manage heavy construction seasons by persuading polite midwesterners to do the zipper merge. Rather than merging as soon as it's safe, drivers will be asked to wait to merge as long as possible after reaching the construction zone for repairs. (AP Photo/Orlin Wagner)  (The Associated Press)

Transportation officials in Missouri and Kansas are encouraging motorists to resist the urge to get in line at the first sign of an upcoming lane closure.

Advocates of the "zipper merge" method say using both lanes for as long as possible shortens lines in construction zones by up to 40 percent. They say it doesn't get drivers through the zone any faster, but it reduces the risk of accidents and eases driver angst.

Missouri started promoting the technique earlier this year ahead of a heavy summer construction season. Kansas followed with a pilot project that started last week using electronic signs to warn drivers of an upcoming merge and encourage them to use both lanes.

Minnesota started promoting the zipper merge idea in 2011, and Washington followed in 2014.