McALLEN — Desired for years, construction is set to start to add two more lanes to the northbound inspection lanes at the Anzalduas International Bridge, bringing the total number of northbound lanes at the bridge from four to six at a time when traffic the last few months has been backed up for significant periods.

The two new lanes will cost $2.7 million, initially funded by the city but will be reimbursed through the Texas Department of Transportation. City commissioners voted on Monday to approve the construction management services, touching off the construction process that officials in McAllen expect will culminate at the beginning of 2020.

Traffic at the Anzalduas Bridge — which is in South Mission but is operated mostly by McAllen staff and federal personnel — has seen daily wait times for vehicles crossing from Mexico into the United States back up for hours in recent months.

Part of the reason: passenger vehicles are no longer allowed during the weekdays to cross northbound on the Pharr-Reynosa International Bridge, the only full-service commercial crossing in the area.

Pharr has had to search for ways to ensure traffic flows northbound on its bridge after President Trump threatened in late March to close the U.S.-Mexico border, followed by the reassignment of hundreds of Customs officers at ports of entry. The duration of this program, which limits crossings for passenger vehicles, in Pharr is unclear, with officials regularly reviewing its progress.

Through various pilot programs, Pharr most recently moved to only allow passenger vehicles to cross northbound on its bridge on weekends after 4 p.m. Cars and other passenger vehicles have instead crossed northbound on the Hidalgo-Reynosa International Bridge or the Anzalduas Bridge.

Trucks, however, can only cross northbound on the Pharr Bridge. The only type of trucks permitted to cross the Anzalduas Bridge are empty trucks heading south bound from the U.S. into Mexico.

Southbound car crossings at the Anzalduas Bridge, however, have increased. Nearly 77,000 cars crossed the bridge going into Mexico in June, compared to about 71,500 in June 2018, the only bridge to see more southbound car crossings in June 2019 than in June 2018. Comparing those same months, the bridge in Hidalgo saw 204,112 cars cross southbound this June compared to 229,976 last June.