Roadworks on State Highway 2 between Masterton and Carterton backed up traffic for more than two kilometres yesterday morning.
Workers resealing the southbound passing lanes running from Norfolk Rd to East Taratahi Rd had left only a single lane in use about mid-morning and stop-go signs and police were at the site to manage the backlog.
The queue of north-bound traffic stretched for more than two kilometres about 10am with some drivers abandoning their places in line and heading back the way they came.
Mark Owen, New Zealand Transport Agency regional performance manager, said there had been work crews resealing the passing lane south of Masterton.
"We became aware that longer than expected delays were happening, so we acted quickly to get traffic flowing again. We did this by freeing up a lane via a contraflow arrangement to enable traffic to flow more smoothly, and this appears to have done the trick.
"We thank motorists for bearing with us while we fine-tuned our traffic management. The work will move to a different location (today), and we will continue with the contraflow arrangement to keep people moving."
The agency was "in the midst of roadworks season", he said, and drivers were being asked to be patient and courteous.
Road work south of Masterton will continue in to next week and work will also start north of Greytown, he said, "where the road surface is due a new lease on life".
"This work will cause some delays, and we ask that motorists allow extra time to enable journeys to remain stress-free."
Mr Owen said all planned roadworks in Wairarapa will be completed before Christmas, which "will mean easier journeys in the New Year on a safer, refurbished State Highway 2".