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The project included upgraded ramps at the Cochiti Interchange and installing an Intelligent Transportation System (ITS) for enhanced roadway monitoring. -
The design foresight accommodated a future third lane on I-25 in the southbound direction, addressing anticipated traffic demands.
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Wilson & Company’s phased traffic control plan on the I-25 Slope Mitigation project safely managed over 100,000 daily vehicles, maintaining flow while protecting both crews and motorists. -
Installation of deep, “soilcrete” columns enhanced roadway stability as a durable solution. -
Larger concrete rundowns effectively managed seepage flows, reducing the risk of water damage and enhancing road durability.
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Drainage improvements included extended pipes and a parallel sub-surface storm drain system.
NMDOT I-25 (MP 264 to MP 267.5) Slope Mitigation and Roadway Improvements (La Bajada)
The New Mexico Department of Transportation (NMDOT) developed the I-25 Slope Mitigation and Roadway Improvements project to address critical roadway instability at La Bajada Hill between mileposts 264 and 267.5. This heavily trafficked corridor connects Albuquerque and Santa Fe, with an average of over 40,000 vehicles traveling on it daily. Wilson & Company and WSP completed the final design for the 3.5-mile stretch, delivering innovative engineering solutions to stabilize the roadway, improve safety, and support future traffic demands. Wilson & Company also provided survey and drainage design.
The project scope involved stabilizing the subgrade, reconstructing outdated pavement, addressing drainage/seepage issues on the fill slopes, and upgrading the Cochiti Interchange (Exit 264) ramps. A first-of-its-kind soil stabilization method was introduced in New Mexico, involving the construction of 1,000 soil-mix columns, 10-foot diameter and up to 50 feet deep, beneath 1.5 miles of roadway. These columns were topped with a load transfer platform (LTP) that supports the pavement and allows for electronic monitoring of soil settlement over time.
Additional roadway improvements included widening the interstate from a 5-lane to a 6-lane divided roadway, separated by a concrete barrier, and upgrading the drainage infrastructure to manage surface and subsurface water flows. An Intelligent Transportation System (ITS) conduit/fiber was installed along with a new Road Weather Information System (RWIS) at the Waldo Canyon Road Interchange (Exit 267) to enhance roadway monitoring and safety.
The $40 million project was completed six months ahead of schedule and $3.5 million under budget. These improvements will significantly enhance the stability and safety of the roadway, reduce travel times, and prepare the corridor for future growth. The successful completion of the I-25 Slope Mitigation and Roadway Improvements project demonstrates the importance of innovation in infrastructure design and the value of collaboration to deliver critical transportation improvements.