CDOT Ready to Keep Mountain Passes Open

In Colorado’s case the term ‘high pass’ is perfectly appropriate because Centennial State has the nation’s largest inventory of high mountain passes. On the state highway system in winter, CDOT maintains eight passes with elevations above 11,000 feet, 12 with elevations between 10,000 and 11,000 feet, and 11 more with elevations in excess of 9,000 feet. Of the 36 passes CDOT maintains for year-around travel on the state highway system, the loftiest is Loveland Pass on U.S. 40 at 11,992 feet of elevation; the lowest is Raton Pass on I-25 on the New Mexico border south of Trinidad at 7,834 feet.

Until 1929, the Colorado Department of Highways did not have the employee base or equipment to keep the state’s major east-west passes open in the winter. An influx of surplus heavy equipment from World War I and improvements in technology allowed the Department to keep Tennessee Pass (elevation 10,424 feet) open in the winter of 1928/29 for the first time, a major milestone.

That’s a far cry from today, when Coloradans and visitors rely on around-the-clock access to all parts of the state via the high passes for many reasons, including travel to some of the world’s best winter recreation. CDOT meets those expectations with a combination of technology, advanced weather modeling and forecasting, and brute force.

CDOT’s top equipment for battling storms on the high passes includes single- and tandem-drive-axle snowplow trucks, rotary snowplows, four-wheel-drive snowplow trucks, caterpillars, motor graders, and front-end loaders. CDOT makes every effort to keep loose snow from accumulating on the highways, then treats the pavement surface with a variety of anti-icers and deicers to keep hard-packed snow and ice from building up.

CDOT’s avalanche mitigation forces are also ready for the 2012/13 winter season. Utilizing a combination of forecasting, snowpack sampling, and attacks on dangerous snow buildup from both the ground via artillery ordnance and from the air, these specialized CDOT crews strive to bring down avalanches in a safe, controlled environment. They do most of their work in the early morning before most motorists are on the road.

“Our maintenance forces are on call 24 hours a day seven days a week during the winter to address every weather situation,” noted CDOT Chief Engineer Tim Harris. “Very often, they miss holidays, athletic events, and family gatherings because of their service. Their dedication to the safety of the traveling public is outstanding.”

In return, CDOT reminds motorists to help out this winter in the following ways:

1. Unless absolutely necessary, try to avoid driving during times of bad weather. Remember, if you aren’t moving in backed-up traffic, CDOT’s snowplows aren’t moving, either.
2. Be sure your vehicle has been inspected and is prepared for winter driving.
3. Carry proper survival gear, food, and water in the event that you are stranded.
4. Call ‘511’ or log onto www.cotrip.org for the latest in road conditions.
5. Drive safely around snowplows. The best place for you to be is well behind the plow. If you must pass, always do so on the left side of the plow and allow yourself plenty of time to clear through the flying snow and to merge safely back into traffic. Never pass a snowplow on the right through the plume from the plow’s blade.

For specific winter driving tips, visit CDOT’s winter driving site by clicking here.

Colorado Highway Passes Maintained by CDOT

Listed in descending elevation

SH 5 to Mt. Evans, which reaches an elevation of 14,150’, is not considered a mountain pass. Maximum is grade 9% to Summit Lake; 15% beyond Summit Lake. This is the highest paved road in North America and is open seasonally.

Milner Pass (10,758’) and Trail Ridge High Point (12,183’) are on U.S. 34 in Rocky Mt. National Park but are not maintained by CDOT. Maximum grade on both is 5.4%. Open seasonally.