The end of 2016 will bring with it completion of some major parts of the massive widening on a long stretch of U.S. 290 that started five years ago. But to the chagrin of drivers, that still means they'll be driving on new pavement as construction continues on parts of the highway for more than a year.

On Wednesday night starting at 9 p.m., crews will do a rare midweek traffic lane switch, shifting the eastbound lanes onto the newly-built westbound freeway between 34th Street and Hollister so workers can start building the center of the freeway. Officials wanted to make the swap so they could complete the segment and return after the holidays with the westbound work behind them, said Karen Othon, spokeswoman for the Texas Department of Transportation for the project.

Construction, meanwhile, will take longer than expected, Othon confirmed. Utility relocations and other delays led officials to revise previous estimates that all the work along the 38-mile widening project would open in 2017. Now most of the project segments will be finished in 2018, though some major changes will come much sooner.

Work is spread along U.S. 290 from Loop 610 to the Waller County line. Officials estimate the widening and associated interchange work at Loop 610, the Sam Houston Tollway and Grand Parkway will cost $1.8 billion, with $1.27 billion of that construction of the 13 separate segments that encompass the overall project.

Regarding Wednesday's traffic switch, TxDOT typically makes significant changes to detours and lanes over weekends when traffic is lighter and officials can correct any issues on Saturday and Sunday. Othon said the upcoming Christmas and New Year holidays convinced officials to finish the work, make the switch and move to other tasks when they return from the holiday break.

The shift is also unique, Cossey said, in involving three different contractors - Williams Brothers Construction, OHL USA and Webber. Normally, the detours would just be in the area built by one contractor.

Though the work on 290 is cheered by elected officials and others as necessary to handle growth, for drivers it has been a years-long slog of narrowed lanes, traffic detours and white-knuckled drives alongside semi-tractor trailers.

"Oh my god, it's terrible. I feel like I am going to die," said Piper Kwasniewski, 29, who lives near the freeway close to Cy-Fair High School, citing how unsafe she feels on the freeway in spots where there are no roadway shoulders so close to heavy trucks.

Construction and lane width reductions have been a constant for commuters for five years, with a sixth and possibly seventh still to go. Work at U.S. 290 and Loop 610 started in June 2011. Crews and construction managers haven't had it any easier, trying to widen and rebuild a freeway, move utilities and install a huge drainage system while keeping traffic flowing.

"It's like a puzzle," said Shane Cossey, the TxDOT engineer overseeing the U.S. 290 project. "It's a lot of working pieces we have to get done."

To keep the freeway open, construction essentially has moved along the freeway's path as well as across it. Traffic moved onto the westbound lanes so crews could build most of the eastbound side, then swapped back so workers could widen the westbound side. Now, along most of the project, work moves to the middle.

None of the changes change the capacity or number of lanes on the freeway, Cossey said.

Crews last week were putting the finishing touches on the road, completing the last small portions of the westbound lanes and readying them for the traffic flip.

Eventually, U.S. 290 will be at least five lanes in each direction with a single reversible high occupancy toll lane from Loop 610 to Texas 6. West of Texas 6, the freeway will be four lanes in each direction with the solo HOT lane.

Othon said TxDOT is still analyzing a proposal by Metro for off-peak high occupancy vehicle lane restrictions along the freeway. Before changes were made to the project in 2014, three reversible HOT lanes were planned down the center of the freeway. To improve transit times in the area, Metro proposed making the innermost lane of each side of the freeway an HOV lane - westbound in the morning when traffic is lighter and eastbound in the afternoon. That way, buses can make quicker return trips to suburban park-and-ride locations along U.S. 290.

"It doesn't impact the construction schedule at all," Othon said, adding officials have time to decide if the proposal is possible.

What will affect openings of portions of the freeway when it's finally widened is other areas, Cossey said. Even as the freeway is completed in sections west of the Loop 610, he said crews will hold off opening places where it will create a bottleneck at spots still under construction.

"Nowhere on 290 are we going to open up to only restrict ... elsewhere," Cossey said.