CDOT to Implement New Pretreatment Strategy Before Snowfall in Denver Metro Area

DENVER—The Colorado Department of Transportation will use a time-tested anti-icing product ahead of a snowstorm as part of its new pretreatment strategy in the Denver metro area. This anti-icing product is specifically made to be applied to roadways before a snowstorm or icestorm to help prevent ice and snow from bonding to the roadway.

CDOT's Denver metro crews recently introduced this product to the Denver metro area to provide a proactive solution to fighting snow. The de-icing products CDOT currently uses have proven to be successful on roadways statewide; however, de-icers—when paired with anti-icing efforts—go above and beyond their normal capabilities, making it easier for plows to clear the roads.

"We're constantly looking for ways to further improve the way we fight snow and ice," said Mike O'Neill, deputy director of maintenance for CDOT's Denver metro region. "We've seen the anti-icing brine mix solution be very successful throughout the United States, Canada, and Europe, and knew this was the right product to use in the Denver metro area."

CDOT makes this product in-house, at a rate of 42 cents per gallon, by mixing rock salt and water to make a 23.3 percent brine solution. A corrosion inhibitor is also added to the mixture before crews begin applying it to the roadways.

Motorists in the Denver metro area can expect to see trucks spraying this anti-icing solution on the roads about eight to 10 hours before snow begins to fall. Motorists will see white stripes along the roadways once the solution has dried.

CDOT is applying anti-icing product on major roadways and known hazard areas including: I-25, I-70, C-470, I-225, US 6, CO 83, CO 88 and more. Crews are also applying the anti-icing product on the I-70 and US Highway 285 mountain corridors.

While other states and countries are using a similar brine mix, CDOT is unique in the fact that it adds a corrosion inhibitor before application.

"CDOT is using inhibitors along with a strict quality control process in place to ensure what we do is above reproach, transparent and in line with industry standards," O'Neill said.

CDOT specifications state that all products must be tested to be at least 70 percent less corrosive than sodium chloride on mild steel metal.

Rivertop Renewables has been awarded a contract from CDOT to supply a bio-based corrosion inhibitor for use with liquid anti/de-icers on the state's roads. The company's inhibitor—named "Headwaters"—is mixed with CDOT's salt brine anti/de-icers to prevent corrosion on bridges and vehicles.

This inhibitor is made of sugar and derived from corn, making it biodegradable and not harmful to watersheds. The corrosion inhibitor also reduces corrosion by approximately 70 percent, compared to straight uninhibited salts.

"We will be putting sugar and salt on major roadways to keep winter drivers safe, and Colorado's economy flowing, while also protecting infrastructure investments and the environment," O'Neill said.

Crews will stop spraying the product once snow starts to fall or temperatures drop below freezing, and will switch over to de-icers.

CDOT asks motorists to please keep a safe distance behind its anti-icing trucks to allow crews to safely conduct their operations. There will be variable message signs in place alerting motorists of anti-icing efforts and slow-moving vehicles. Smaller signs will also be placed on CDOT trucks following the anti-icing trucks, alerting motorists of the operations.