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Work begins on State Route 189 improvements in Nogales

Work begins on State Route 189 improvements in Nogales

May 15, 2020

PHOENIX – An Arizona Department of Transportation project that will speed up international commerce, boost the economy and make Nogales traffic safer has begun near Arizona’s southern border.

To make way for improvements to State Route 189 (Mariposa Road) in Nogales, the 3.75-mile road that connects the international border with Interstate 19, crews have been clearing brush from the path of the first of two flyover ramps that will connect northbound SR 189 with northbound I-19. Construction is scheduled to start in earnest next week and take about 18 months.   

“The improvements coming to State Route 189 are not only going to support international commerce and economic growth but make Mariposa Road safer for the local community,” ADOT Director John Halikowski said. “When everything is finished, these improvements are going to make it even better to live and do business in Nogales, Santa Cruz County and southern Arizona.”

Construction will begin almost immediately on the flyover ramp connecting northbound SR 189 with I-19. The ramp will begin west of Frank Reed Road, curve south of SR 189, cross over I-19 and SR 189 before connecting with I-19 just north of the current entrance ramp. Flyover ramps connecting with both directions of I-19 will eliminate the need for commercial trucks to stop for as many as three traffic lights before beginning the trip north toward Tucson and markets across the U.S.

Drivers using SR 189 should watch for short-term lane closures for exploratory drilling. No other lane restrictions are planned in the near future.

The $134 million project also includes building a roundabout at SR 189 and Target Range Road as well as a traffic signal, drainage improvements and additional work, including improvements east of I-19 and on Grand Avenue. The existing freeway on- and off-ramps will remain in use until the project is completed.

The flyover ramps also will improve safety by reducing truck traffic on SR 189. Most trucks will leave SR 189 before reaching Frank Reed Road, the primary entrance to Nogales High School, improving safety for students and their parents.

The work is funded in part by a $25 million investment by the Arizona Legislature and a $25 million federal TIGER (Transportation Investment Generating Economic Recovery) grant.

For more information, please visit azdot.gov/SR189.