• Arizona Contractor & Community

Digging Through the Archives – New Pueblo’s I-19 Construction

By William Horner



When the conversation turns to “Tucson construction,” there’s one company that is inevitably discussed: Karl Ronstadt’s and Howard King’s New Pueblo Constructors. New Pueblo advertised itself as “a company with young management and with old ties to the region it serves,” when it began in 1959. The firm was active until the mid-1990s and left its footprint across the Southwest. If you’ve ever stopped for dinner in Green Valley, flown into Albuquerque, fished in Lake Patagonia, spent the night at Rio Rico, or scored a birdie at Tucson National Golf Course, you’ve enjoyed the work of their company.


New Pueblo Cat crawlers pushing 631 scrapers on I-19, 1967.


Although retired, Ronstadt keeps up-to-date with current construction and is a valuable resource about past contractors and projects. Ronstadt is also a longtime friend of Arizona Contractor & Community magazine, which spotlighted New Pueblo in its first issue devoted to Tucson in Winter 2013.


For this follow-up Tucson issue, I’m highlighting New Pueblo’s extensive highway work, focusing on Interstate 19 that runs 63 miles south from Tucson to Nogales. Construction of I-19 started in 1962 and was finished in 1978. A unique attribute of the freeway is that signage was provided in kilometers rather than miles. The metric system was used since it was close to the border and the U.S. was pushing its adoption at the time.


New Pueblo was the low bidder on 4.5 miles of I-19 in August 1966. Ronstadt stated, “We started around Rio Rico Drive and headed south past Ruby Road, Mariposa Road, and into Nogales. Mariposa and I-19 went south to the border to Arroyo Blvd. and Grand Avenue. We also had another contract for three miles of new road from Mariposa Interchange to the border.”


The project faced an odd problem that winter. “Pre-wetting operations, struck by falling night-time temperatures (as low as 12 degrees) froze over, clothing desert cactus and scrub brush in a paradoxical icy armor…becoming a fairyland of ice,” reported Arizona-New Mexico Contractor & Engineer in 1967. “Shutterbugs and the plain curious nearly caused a full-scale traffic jam as they flocked from Tucson and Nogales to see the spectacular sight. Day-time temperatures, however, which soared back up to the high 60’s soon melted the ice and restored order.”


The publication noted that the cold weather had halted work. “All work has been completed there except a road mix surface, which requires 70-degree temperatures for the go-ahead.”


Paving I-19 at Green Valley, 1969.


Besides the low temperatures, Ronstadt said there were other challenges. “One bridge was slanted and curved with a skewed elevation, making the rebar skeleton a nightmare to install,” he says. Despite the difficulties, New Pueblo completed the project by its October 1967 deadline. This accomplishment was aided by New Pueblo’s second construction office and commercial ready-mix plant on the east side of I-19 at Ruby Road.


“We started another phase of I-19 at Duval Mine Road, running about 5-miles to Canoa Ranch Road,” recalls Ronstadt. “The Santa Cruz River at Florida Canyon Wash, we operated the Green Valley Gravel pit on the east side of the freeway supplying aggregate and asphaltic concrete.” Ronstadt says they called it the FICO plant because the land was owned by the Farmers Investment Co., headed by Keith Walden. “We paid FICO a royalty for every ton mined from the Green Valley Gravel pit,” he says. “We provided concrete to the Duval and Anaconda mines and concrete read-mix to local contractors from Tucson to the Mexican border.”


#NewPuebloConstructors #KarlRonstadt #HowardKing #I19

To read the rest of this article, you are invited to purchase the digital issue here.

This article originally appeared in the bimonthly Arizona Contractor & Community magazine, Nov/Dec 2020 issue, Vol. 9, No. 6.


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