Construction crews in January are preparing to open new eastbound lanes at the Plano Parkway-Preston Road intersection, a significant step toward improving traffic conditions at the meeting point of two major Plano thoroughfares.

The new lanes are expected to open in late December or early February and are part of a more than yearlong project to replace the eastbound lanes, add turn lanes and conduct improvements on the high-volume intersection, said Daniel Prendergast, assistant director of public works for the city of Plano.

“You’ll see improvement [in traffic] on Plano Parkway,” Prendergast said of the lane openings. “You may actually see improvement on Preston because there [will be] only one signal there instead of two.”

Crews have spent the better part of the past year constructing new lanes in Plano Parkway’s large median while drivers continued to use the existing eastbound lanes. The new eastbound lanes will run closer to the existing westbound lanes, eliminating the need for a second traffic signal and maximizing the distance between the intersection and President George Bush Turnpike to the south.

Construction on Preston Road will continue through April, Prendergast said. After crews finish their work on Preston, the effect on traffic will become less intensive.

The project will ultimately expand Preston Road to seven lanes in each direction, including four thru-lanes, two left-turn lanes and one right-turn lane.

The city project cost roughly $5 million, with 90 percent of the funding coming from state and federal sources.

The most intensive construction is expected to last during the day and lighten during commuting hours.