Building a road through the treacherous terrain of Colorado’s Rocky Mountains was once considered an impossible feat. Roads require a specific shape that Earth often doesn’t naturally provide—fairly flat, yet not completely flat. In this article, we’ll explore the incredible engineering challenges faced in constructing I-70, a highway that traverses Colorado’s rugged landscape. From dealing with avalanches to environmental considerations, this road is a testament to human ingenuity and determination.
The Quest for the Perfect Slope
The first challenge in road construction is finding the right slope, both linearly and laterally. Roads must be flat enough to ensure safety, yet not so flat that they become hazardous. The American Federal Highway Administration even has a formula to determine the suggested slope for turns. However, this is a subject of endless debate among road designers and mathematicians.
Choosing the Route: A Delicate Balance
When planning I-70’s route, engineers had to consider the delicate balance between a flat cross-section and the need for a road to traverse the Colorado Rockies. The Northern route initially seemed favorable, following a river for a relatively flat linear gradient. But it was rejected due to its longer, less direct path.
The Tunneling Solution
To conquer the Continental Divide, engineers faced a choice: construct a high-elevation road or build the world’s highest elevation road tunnel. They opted for the latter, leading to the construction of an astonishing tunnel at 11,000 feet above sea level.
A Controversial Decision: Veil Pass
The route to I-70 took an unexpected turn when it was decided to divert the road through Veil Pass instead of Red Buffalo Pass. This decision, made to protect a pristine wilderness area, added length to the highway but came at a lower cost.
Earthwork: Reshaping the Landscape
Creating a road involves extensive earthwork, including cutting and filling. This process requires meticulous planning and calculations to determine how much earth needs to be moved. In Colorado’s challenging terrain, this task is both complex and expensive.
Managing Runoff and Erosion
Managing water runoff and preventing erosion is crucial in road construction. Colorado’s unique geography, with steep mountain slopes, adds to the challenge. Techniques like retaining walls, drainage systems, and re-vegetation help mitigate these issues.
Challenges of Avalanche Control
Avalanches pose a significant threat to I-70, especially in the winter. To prevent disaster, controlled avalanches are triggered to clear snow and debris from avalanche paths. This practice ensures the safety of motorists, even in treacherous conditions.
Glenwood Canyon: A New Challenge
In recent years, Glenwood Canyon has become the most sensitive section of I-70. The canyon’s unique geography and environmental concerns require constant management and vigilance to keep the highway open.
Conclusion: A Never-Ending Battle
I-70 in Colorado is a testament to human engineering prowess and adaptability. As the landscape and challenges evolve, the Colorado Department of Transportation continues to adapt and ensure the safety and functionality of this crucial transportation artery through one of the most challenging terrains in the United States.