Construction will begin before the end of the year to implement a longstanding plan to overhaul the complicated and congested intersection of Plano Parkway and Preston Road.

City officials expect the $5 million project to last more than a year and ultimately alleviate traffic backups at the intersection, where cars often jams back through multiple lights during rush hour as drivers navigate the area north of President George Bush Turnpike.

One of the intersection’s defining qualities is the large, grassy median between the eastbound and westbound lanes of Plano Parkway. The east-west thoroughfare splits on each side before reaching Preston Road, resulting a complicated network of traffic lights, turn lanes and U-turn merging opportunities.

As part of the construction, crews plan to demolish the existing eastbound lanes after constructing new eastbound lanes next to their westbound counterparts. Because most of the construction in the earliest phases will take place in the median, project-related traffic slowdowns are expected to be somewhat lessened, wrote Daniel Prendergast, engineering manager for the city's community investment program, in an email.

As a result of the newly constructed lanes, the city will “maximize the distance between between the PGBT and Plano Parkway intersections” and get rid of the existing eastbound Plano Parkway traffic signals, according to an Oct. 23 staff memo.

The intersection will also be widened as crews add new thru-lanes and turn lanes for all four legs of the intersection, the memo reads.

“Lane closures will be required in order to complete the work.  However, the work has been sequenced to minimize rush hour lane closures,” Prendergast wrote.

In June, the city updated an agreement with the Texas Department of Transportation that outlined 90 percent of the funding for the project would come from federal and state sources, with the remaining 10 percent coming from the city.

The agreement, originally struck with the agency in 2004, had estimated a similar project at the intersection would cost roughly $2.8 million. The new agreement in June expanded the original budget and updated other terms of the partnership, according city documents.