SANTA TERESA, N.M. (AP) — Work will begin soon to replace existing vehicle barriers along the U.S.-Mexico border in southern New Mexico with a new bollard wall.

U.S. Customs and Border Protection announced that a groundbreaking near the Santa Teresa port of entry on Monday will mark the official start of construction along a 20-mile stretch of the border.

The $73 million contract for the work was awarded to a Montana company in February.

With a new wall, federal officials say agents working in southern New Mexico will be better equipped to stop drug trafficking and illegal crossings in the area.

Environmentalists have sued over the project, saying the federal government overstepped its authority in waiving laws as a way to speed construction. A federal judge recently sided with the government in a similar case in California.