Denver Airport's Heated Runways: A Unique Feature Explained

Denver International Airport (DEN) is the largest airport in the Western Hemisphere by land area, and the third busiest airport in the United States by passenger traffic. With its high elevation and hot summers, the airport's runways need to be long to accommodate aircraft take-off. DEN has six runways, five of which measure 12,000 feet in length, and one that measures 16,000 feet, making it the longest public-use runway in North America. While DEN has an efficient runway layout, it is unclear whether these runways are heated. The airport has previously experienced closures due to heavy snowfall, and has invested in snow removal equipment to reduce runway occupancy times.

Denver International Airport's snow removal methods

Denver International Airport (DEN) has a comprehensive snow removal strategy, employing a combination of trained personnel, specialised equipment, and chemicals to ensure safe operations during winter.

Snow Removal Personnel

The airport has nearly 600 trained snow removal personnel who are responsible for clearing runways, taxiways, and other surfaces. These crews are deployed as soon as snowfall begins and work around the clock to keep the airport operational.

Snow Removal Equipment

DEN has a large inventory of snow removal equipment, including approximately 324 pieces of airside equipment and 275 pieces of landside equipment. This equipment includes blowers, brooms, blades, plows, runway sanders, snow melters, chemical trucks, loaders with box plows, and bobcats.

Following the 2006 blizzard, the airport invested in multi-function machinery that can plow, sweep, blow snow, and spread liquid and sand products simultaneously. This investment has significantly reduced the time needed to clear a runway from 45 minutes to under 15 minutes.

Chemicals and De-icing

The airport uses a range of chemicals, sand, and de-icing fluids to prevent ice formation and improve traction. For landside pavement, a product similar to magnesium chloride, called Apex, is used. When temperatures drop below freezing, sand is used instead of chemicals to improve traction. Potassium acetate is the chemical of choice for treating runway and taxiway surfaces.

Aircraft de-icing is handled by airlines or their contractors, and DEN has invested in technology to optimise the process, reducing wait times and saving fuel costs.

Recognition

In 2020, DEN was recognised for its outstanding snow and ice removal operations during challenging winter conditions with the Balchen/Post award, presented by the Northeast Chapter of the American Association of Airport Executives (AAAE).

The cost of heated runways

Heated runways are not a new idea, but they have not been widely adopted. The main reason for this is the high cost of installing and operating such systems.

Installation Costs

Estimates for the cost of installing a heated runway vary. One source suggests that it would cost around $200 million to install heating in the busiest areas of an average-sized airport. Another source gives an estimate of $53 million to install electric heating on a 150 x 10,000-foot runway. At some of the world's biggest and busiest airports, installation costs could top £150 million.

Operating Costs

The power requirements for keeping a runway heated are immense, and this has a significant impact on operating costs. One source calculates that, during a snowstorm, Chicago O'Hare airport would require 600,000 kWh of power to melt the snow on its runways. At Illinois power prices, this would cost at least $100,000 per hour.

Alternative Methods

In comparison, alternative methods of keeping runways clear during winter weather are much more cost-effective. Airports typically use snow ploughs, sweepers, and chemicals to clear runways and prevent ice from forming. While these methods do not completely eliminate delays and cancellations, they are much cheaper than installing and operating heated runways.

Other Considerations

In addition to the high costs, there are other challenges associated with heated runways. For example, the management of meltwater can be difficult and may cause safety issues if not properly designed. There are also concerns about the potential for heated runways to create turbulence, and the possibility that heating systems would not be able to keep up with heavy snowfall or very cold temperatures.

Overall, while heated runways may seem like an attractive solution to winter weather delays, the high costs and other challenges mean that they are not a practical option for most airports.

The challenges of heating runways

Heated runways are not a common feature of airports, despite the weather-related delays that plague airports during the winter months. There are several challenges associated with heating runways that make their implementation difficult.

Firstly, the amount of power needed to keep runways heated is a significant hurdle. The installation and operation of a heating system would require a large amount of electricity, with some estimates for installation alone topping £150 million at the world's biggest and busiest airports. The high energy costs of such a system are often cited as a reason for the aviation industry's reluctance to adopt heated runways.

Another challenge is the management of meltwater. The runoff from heated surfaces must be properly designed to avoid safety issues and potential flooding. In certain weather conditions, a heated surface may even increase the need for mechanical snow removal and create safety hazards.

Additionally, heating a runway does not address all the problems caused by winter weather. Strong winds, poor visibility, and fog are still issues that must be contended with, even with a heated runway. Snow and ice accumulating on aircraft preparing for takeoff is another problem that heating runways does not solve.

Furthermore, the durability of the heating system is a concern. Runways must be able to withstand the weight of aircraft, which exert much higher pressure than cars. This requires a heating system that is extremely strong and durable, adding to the overall cost and complexity of the project.

Finally, while heated runways may reduce delays caused by snow and ice on the runway, they do not eliminate the need for snow clearance. Airports would still need to maintain extensive equipment and trained teams to deal with snowfall, as well as accurate forecasts to plan and make timely decisions.

The impact of weather on airport operations

Weather conditions can have a significant impact on airport operations, affecting everything from runway conditions to aircraft performance. While airports employ various strategies to mitigate weather-related disruptions, delays and cancellations are sometimes inevitable.

One of the most significant challenges posed by weather is the impact of ice, snow, slush, and rain on runway friction, which can affect the braking and acceleration performance of aircraft, compromising safety. To counter this, airports engage in snow and ice removal operations, deploying specialised equipment and trained personnel to clear runways and treat surfaces with chemicals to lower the freezing point of water. However, these efforts can be time-consuming, impacting airfield operations and turnaround times, leading to delays and, in some cases, cancellations.

Additionally, adverse weather conditions can create challenges beyond the runway. Strong winds and poor visibility, for example, can hinder aircraft takeoff and landing, even if the runway itself is clear. Fog is also more common during winter, further complicating operations. In such cases, heating the runway would not provide a solution.

Another challenge is managing the meltwater from heated surfaces, which, if not properly addressed, can create safety issues. Furthermore, there are weather situations where a heated surface may even increase the need for mechanical snow removal and create additional safety hazards.

The implementation of heated runways also faces practical and economic obstacles. The amount of power and the associated costs required to heat runways are significant, with installation estimates exceeding £150 million at major airports. Additionally, the construction, maintenance, and operation of such systems would likely outweigh any potential benefits or savings in de-icing chemicals and snow removal.

While heated runways may seem like a straightforward solution to weather-related disruptions, the reality is more complex. Airports must continually adapt and improve their operations to minimise delays and cancellations while ensuring the safety of passengers and staff. This includes investing in new equipment and technologies, such as Denver International Airport's purchase of state-of-the-art snow removal machinery, which has significantly reduced the time needed to clear runways.

Denver Airport's runway layout

Denver International Airport (DEN) has one of the most efficient runway layouts in the United States. It features six non-intersecting runways: five measuring 12,000 feet in length, and one (16R/34L) measuring 16,000 feet, which is the longest commercial runway in North America. The airfield is divided between the east and west sides, with four parallel north-south runways and two east-west crosswind runways. This configuration maximises efficiency and accommodates the high volume of air traffic that passes through the airport.

The runway layout was chosen to handle the predominant wind patterns in the area, which typically blow north and south. The four parallel runways allow multiple planes to take off and land simultaneously, reducing delays and accommodating more flights. The east-west runways enable operations to continue smoothly during periods of strong crosswinds and various weather conditions.

The Denver International Airport covers 52.38 square miles (135.66 square kilometres) of land, making it one of the few major U.S. airports with room for expansion. The airport has the capacity to add six to twelve additional runways in the future, ensuring its ability to serve the growing air traffic demand.

Frequently asked questions