Navigating mountainous terrains presents unique challenges for drivers, especially those operating heavy vehicles. Steep descents can quickly become hazardous, leading to brake failure and potentially catastrophic accidents. Enter the Runaway Ramp, a vital piece of infrastructure designed to provide a safe escape route for vehicles experiencing brake problems on steep downgrades. While often unseen and thankfully unused by most drivers, these ramps are a silent guardian on mountainous highways, ready to prevent disaster. Colorado, with its extensive Rocky Mountain ranges and busy Interstate 70 (I-70) corridor, is home to the most heavily used runaway truck ramp in the United States, highlighting the critical role these safety features play.
This article delves into the world of runaway ramps, exploring why they are essential, how they function, and what drivers need to know to ensure safety on steep mountain roads. We’ll examine the busiest runaway ramp in the US, located on I-70 near the Eisenhower Tunnel in Colorado, and understand why it sees so much use, particularly during the summer months. Whether you are a seasoned trucker or a family heading to the mountains for a vacation, understanding runaway ramps can be a crucial part of safe mountain driving.
What is a Runaway Ramp and Why Are They Necessary?
A runaway ramp, also known as an escape ramp or emergency ramp, is a safety device designed to stop vehicles that are experiencing brake failure on steep downhill roads. Typically positioned alongside highways with significant downgrades, these ramps offer a dedicated path for drivers to safely decelerate and stop their vehicles when their brakes become ineffective.
The necessity of runaway ramps stems from the physics of driving on steep grades, particularly for heavy vehicles like semi-trucks. As vehicles descend, gravity increases their speed, requiring constant braking to maintain control. Prolonged and heavy braking, especially in hot weather, can lead to a dangerous condition known as brake fade.
Brake fade occurs when the friction surfaces in the brakes overheat. This excessive heat reduces the friction between brake pads and rotors or brake shoes and drums, diminishing the braking power. In severe cases of brake fade, the brakes can become completely ineffective, leaving the driver with no way to slow down or stop the vehicle using the regular braking system.
This risk is amplified in mountainous regions like Colorado, where long, steep downgrades are common. The I-70 corridor, a major artery through the Rockies, presents such challenges, especially on the western side of the Eisenhower Tunnel. The combination of steep inclines and high traffic volume, particularly during peak travel seasons like summer and holiday weekends, significantly increases the likelihood of brake fade and the potential need for runaway ramps.
Runaway truck ramp entrance near the Eisenhower Tunnel on I-70 in Colorado. This image highlights the signage and the ramp’s position relative to the highway, crucial for drivers experiencing brake failure to identify and utilize it.
The I-70 Lower Straight Creek Runaway Ramp: Busiest in the US
The Lower Straight Creek runaway truck ramp on westbound I-70, just past the Eisenhower Tunnel, holds the distinction of being the most heavily used runaway ramp in the United States. This isn’t due to poor road design, but rather a combination of geographical factors and traffic patterns that make this particular stretch of highway especially demanding on vehicle brakes.
According to the Colorado Department of Transportation (CDOT), the steep and deceptively long descent after the Eisenhower Tunnel, coupled with consistently high traffic volumes, contributes to the frequent use of this ramp. As Tamara Rollison, CDOT Communications Manager, explains, “When you go down that hill, it’s pretty steep. It’s deceivingly steep.” This steepness, combined with the constant braking needed in heavy traffic, leads to brake overheating and fade, often culminating in drivers needing to use the runaway ramp.
“They’re going to come down that pass. And usually they’re not hot enough, and their brakes haven’t experienced enough wear yet to hit the upper runaway ramp, but once they get towards that lower runaway ramp, they’ve experienced total brake failure,” Rollison further elaborated. This “brake fade” phenomenon is particularly prevalent during summer months when ambient temperatures are high, and brake systems are already working harder to dissipate heat.
Charlie Stubblefield, owner of Mountain Recovery, a prominent towing company servicing the I-70 corridor, confirms the increased ramp usage during summer and peak seasons. “Labor Day is coming up, we definitely ramp up our team… We make sure we’re out here right away when the sun comes up, all the way to 8, 9, 10 o’clock at night, as long as people are out on the roads.” His team regularly recovers vehicles from the Lower Straight Creek ramp, underscoring its crucial role in preventing accidents. In 2023 alone, Mountain Recovery responded to approximately 12 trucks on this single ramp.
How Runaway Ramps Work: A Gravel Pit to Stop a Truck
Runaway ramps are ingeniously designed to bring speeding vehicles to a safe stop using simple physics. The most common type of runaway ramp, like the one at Lower Straight Creek, utilizes a deep bed of loose gravel, often referred to as “clear stone.”
Charlie Stubblefield describes clear stone as “like little gravel, probably like half an inch to three-quarters of an inch round… There’s no fine [stones] in there, which means that that stone is kind of like a ball pit, right? When you jump in as a kid and it just sucks you down in, and it’s hard to get out of.”
This “ball pit” effect is precisely how the gravel ramp works. As a vehicle enters the ramp, its tires sink into the loose gravel. The resistance from the gravel creates a significant drag force, rapidly decelerating the vehicle. The deeper the vehicle sinks, the greater the resistance, effectively bringing even heavy trucks to a stop within a relatively short distance.
Different runaway ramps may use slightly different materials and designs. Some older ramps might incorporate finer stone, while newer designs may optimize the size and type of gravel for maximum stopping power. The steep incline of the ramp itself also contributes to deceleration, working in conjunction with the gravel bed. However, this steepness also presents challenges for recovery, as tow trucks sometimes need to launch themselves into the ramp to reach stranded vehicles.
Close-up view of a runaway truck ramp’s gravel bed. This image showcases the “clear stone” – the loose gravel specifically designed to create resistance and safely stop runaway vehicles by allowing tires to sink in.
Using a Runaway Ramp: It’s Not Just for Trucks and It’s Not a Parking Spot
It’s a common misconception that runaway ramps are solely for semi-trucks. In reality, any vehicle experiencing brake failure on a steep grade can and should use a runaway ramp. As Tamara Rollison from CDOT emphasizes, “If you’re driving your Subaru, let’s say, and you’re going down westbound, I-70, and your brakes don’t work, you can use that runaway truck ramp. It’s there to use in an emergency so you can make a safe exit off the interstate…”
Runaway ramps are strictly for emergency use only. They are not rest stops, scenic overlooks, or places to pull over if you’re tired. Misusing a runaway ramp can be dangerous and impede its availability for drivers in genuine emergencies. Unfortunately, as Charlie Stubblefield recounts, misuse does occur: “There are families in a suburban get out of the vehicle and are at the bottom of the runaway ramp. We’re like, ‘No no, you got to get out of here.’ This is not the place to stop. I’ve seen people that ski or snowboard down the ramps.”
Another common concern is the fear of legal repercussions or costs associated with using a runaway ramp. Rollison clarifies that “Colorado State Patrol does not issue a ticket for drivers that use the ramp and drivers are not charged for CDOT maintenance crews to clear the ramp for future use.” The primary cost for drivers using a ramp is typically the expense of hiring a third-party tow truck to recover their vehicle, as CDOT maintenance crews clear the gravel bed to ensure it’s ready for the next emergency.
Mountain Driving Safety: Prevention is Key
While runaway ramps are life-saving safety nets, the best approach is to prevent brake failure in the first place. CDOT and experienced drivers like Charlie Stubblefield offer valuable tips for safe mountain driving:
- Maintain a Safe Speed: Adhere to speed limits, especially on downgrades. Excessive speed increases braking demands and heat buildup. Stubblefield advises, “We want trucks be going 35 miles an hour once they hit this tunnel. We want trucks to be going 45 miles an hour once they crest over the top of Vail Pass. If they’re doing 65 miles an hour coming out of that tunnel, their brakes alone can’t stop them.” This advice holds true for passenger vehicles as well.
- Use Engine Braking and Transmission: For trucks, engine brakes and proper gear selection in the transmission are crucial for controlling speed on downgrades. These systems use engine compression to slow the vehicle, reducing reliance on wheel brakes. Passenger vehicles can also benefit from downshifting to lower gears on steep descents to utilize engine braking.
- Pre-Trip Vehicle Checks: Ensure your vehicle’s brakes are in good working order before embarking on a mountain drive. Check brake fluid levels, brake pad thickness, and overall brake system condition.
- Utilize Cooling Stations and Chain-Up Areas: CDOT provides designated cooling stations along I-70 where drivers, especially truckers, can pull over to allow their brakes to cool down. These areas also often serve as chain-up stations during winter, further emphasizing safety preparedness.
- Educate Yourself on Mountain Driving: Familiarize yourself with mountain driving techniques and potential hazards before your trip. CDOT provides resources and guidelines for safe mountain driving.
Tamara Rollison, CDOT Communications Manager, emphasizes the importance of driver education and awareness regarding runaway ramps and safe mountain driving practices. Her role highlights CDOT’s commitment to road safety and driver information.
Engineering Safety: Where and Why Runaway Ramps Are Built
The placement of runaway ramps is not arbitrary; it’s a carefully considered engineering decision. CDOT engineers assess various factors to determine the need and location for these critical safety features. Tamara Rollison explains, “It is an engineering decision as to where these runaway ramps go… We also take a look at what the traffic volume is like, what the use is like in in the need, and it’s really based on the need.”
Factors influencing runaway ramp placement include:
- Steepness and Length of Downgrade: Ramps are primarily built on highways with significant and prolonged downhill sections where brake fade risk is high.
- Traffic Volume: High traffic volume increases braking frequency and the overall risk of brake-related incidents, justifying the need for ramps on busy routes.
- Accident History: Areas with a history of accidents related to brake failure are prime candidates for runaway ramp construction.
- Terrain and Space Availability: Engineers must consider the surrounding terrain and available space when designing and positioning a runaway ramp to ensure it is effective and safely accessible.
Runaway ramps are a testament to proactive safety engineering, providing a crucial last resort for drivers facing brake emergencies. By understanding their purpose, function, and proper usage, and by practicing safe mountain driving techniques, all drivers can contribute to safer roads in mountainous regions. For more information on mountain driving safety and runaway ramps, drivers are encouraged to consult resources provided by the Colorado Department of Transportation and other relevant authorities.
Charlie Stubblefield, owner of Mountain Recovery, provides expert insight based on his experience recovering vehicles from runaway ramps. His perspective as a tow truck operator underscores the real-world importance and frequent use of these ramps.
The Eisenhower Tunnel portal, a key landmark on I-70. This image contextualizes the location of the heavily used runaway ramp discussed in the article, situated on the westbound descent after exiting the tunnel.
