Pothole season in Maryland has come early, but with the weather fluctuating so much, the State Highway Administration can't apply a more permanent fix to potholes. In the meantime they use a cold patch, which should last until the weather is consistently around 50 degrees. (Ulysses Muñoz / Baltimore Sun video)
With record rain last year and recent temperatures fluctuating wildly in the Baltimore region, potholes are cropping up earlier than usual, according to the State Highway Administration.
They don’t come cheap: The state agency spent $3.1 million to patch 25,000 square yards of potholes in the 2018 fiscal year, spokeswoman Shanteé Felix said Wednesday.
How do potholes form?
Any number of factors — including the vehicles driving over them — can play a role in deteriorating roads and highways, but moisture and temperature are two main culprits, the SHA says.
Moisture can seep into crevices in asphalt or concrete, and when temperatures drop, the moisture freezes, causing the pavement to expand. When the temperatures rise, the ice thaws and the pavement contracts, forming a pothole.
How are they fixed?
Crews repair potholes using two main methods: a cold patch, which is a temporary fix, and hot-mix asphalt, which requires temperatures of 50 degrees or warmer.
Cold patches are poured from bags of asphalt and tamped down over the pothole. While cold patches are temporary, they can be applied regardless of temperature. SHA crews often carry asphalt for cold patches in their trucks, and they patrol for potholes after winter storms.
Hot-mix asphalt is the same stuff crews use to pave entire roads, and often it is used to cover the entire area of a pothole-pockmarked road. But it’s got to be warm enough to adhere to the existing road, which can present a problem this time of year.