SAN ANTONIO – As cold weather makes its way to the San Antonio area, KSAT received a behind-the-scenes tour of a TxDOT facility that creates the brine used on highways to help keep drivers safe.
Brine is a mixture of water and salt commonly used by TxDOT on roadways during freezing conditions. Its primary purpose is to lower the water’s freezing point, helping to prevent ice from forming on the road surface.
TxDOT spokesperson Tanya Brown explained that brine prevents precipitation from freezing and bonding to roadways.
Brine works by lowering water’s freezing point. When salt, such as sodium chloride, is mixed with water, it breaks into ions that stop water molecules from forming ice.
Typically, water freezes at 32°F (0°C), but adding salt makes it harder for the water to freeze, lowering the temperature at which it can turn to ice.
Brown said their trucks could carry 1,500 to 5,000 gallons of brine, spraying major corridors like U.S. Highway 281, I-10 and I-35.
“We did spray in some areas, I-10 and I-35, Guadalupe County, Kerr County, Medina County. So we kind of monitor the weather and then we try to hit those locations that we expect that there could possibly be some freezing weather,” said Brown.
Brine is typically sprayed on roadways using specialized trucks called brine applicators. The trucks are equipped with a large tank that holds the brine solution.
Not only does it help prevent the ice from forming, but it helps prevent the ice, if it does form, to bond to the asphalt making for an easier removal, Brown said.
Brine can also be applied to roads to help melt any existing ice or snow by lowering the freezing point and making it more difficult for the ice to refreeze.
Brown added that sand or aggregate can be used for traction on elevated surfaces. While it doesn’t melt ice, Brown said it helps drivers maintain better control of their vehicles by providing a gritty surface.
She said it’s commonly used when the temperature is too low for salt to be effective. Each of these methods is selected based on the specific weather conditions.
Drivers are also advised to wash their vehicles with brine after driving on highways.
“Anytime you have salt and water, it can lead to rust. So, we definitely want to wash the vehicle after the weather event,” Brown said. “Make sure you get the undercarriage of your vehicle a good rinse.”
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