The aging storm water tunnel beneath the city of Nogales, extending from the Mexican side of the border, must be replaced before it collapses, Nogales city officials and federal authorities say.
Estimates are that the work will cost up to $10 million.
The 650-foot-long tunnel, which runs beneath the Nogales Port of Entry, was the topic of a meeting last week of the International Water and Border Commission. Engineers on both sides of the border presented their findings.
Commission spokeswoman Lori Kuczmanski said the concern for the structural stability of the tunnel is increasing.
"The port of entry was put there 23 years ago, and basically water has permeated through the concrete so this is being done to prevent further damage,” Kuczmanski said.
The General Services Administration says there is no timeline yet for construction, but officials there said the project is moving forward because while stable for now, the tunnel grows weaker every year.