Ant hills in a driveway are usually the result of pavement ants, which favor nesting beneath hardscapes like concrete, asphalt, or pavers. These ants excavate the soil or sand underneath the surface to construct their extensive network of tunnels and chambers. Their tunneling activity displaces the substrate, pushing small piles of dirt or sand up through cracks and joints, which forms the visible ant hill. Over time, this constant soil removal can undermine the base layer, potentially leading to slight settling, unevenness, or wobbly pavers. Addressing these mounds requires a strategy that targets the hidden colony below, not just the surface ants.
Quick and Non-Toxic Removal Methods
One of the quickest ways to deal with a visible ant hill is to use boiling water, which can kill ants on contact and potentially penetrate deep enough to eliminate a portion of the colony. Carefully pour at least one gallon of boiling water directly into the main entrance hole to maximize penetration. This method can damage asphalt driveways or loosen the binding materials in some paver joints due to the intense heat.
A safer alternative is a simple dish soap and water solution, which breaks down the ants’ protective waxy exoskeleton. Mix one cup of water with about half a cup of liquid dish soap and slowly pour the mixture into the ant hill entrance, ensuring it soaks into the tunnels. This surfactant action suffocates the ants by blocking their breathing passages, offering a low-toxicity method of control.
Household vinegar or a mixture of baking soda and vinegar can be effective, although they may only repel or kill ants near the surface. Vinegar disrupts the pheromone trails ants use for navigation, causing confusion and deterring them. For the baking soda method, push a skewer into the hill to create a larger opening, pour baking soda inside, and follow with vinegar to cause a foaming reaction that penetrates the nest.
Targeted Chemical Strategies for Colony Elimination
For more permanent control, eliminating the entire ant colony, including the queen, is necessary, which often requires a targeted chemical approach. The two primary methods are applying insecticide dusts or granules directly to the hill or using ant baits. Granular treatments, which often contain active ingredients like bifenthrin, are sprinkled around the ant hill and activated by watering them in, allowing the insecticide to move into the underground tunnels.
Ant baits are effective for total colony elimination because they leverage the ants’ foraging behavior. Worker ants are attracted to the bait—which is formulated as a gel, liquid, or granular station—and carry the slow-acting poison back to the nest to feed the queen and larvae. The delayed toxicity ensures the poison is distributed throughout the colony before the workers die, leading to the destruction of the entire nest.
When placing baits on a driveway, secure bait stations near the edges of the pavement or directly over cracks where ant activity is observed. Applying insecticidal dusts, such as those containing diatomaceous earth or boric acid, directly into the cracks and crevices also creates a barrier that workers must cross. Diatomaceous earth works mechanically by causing dehydration, while boric acid acts as a stomach poison, and both are carried back to the colony.
Preventing Future Ant Hill Damage
Preventing future ant hills in the driveway involves structural maintenance and environmental deterrence to eliminate potential nesting sites. Sealing any cracks in concrete or asphalt with an appropriate sealant or caulk is the first step in denying ants entry. This removes the access points they use to begin excavation beneath the surface.
For paver driveways, it is important to regularly re-sand the joints between the stones with polymeric sand, which hardens and prevents ants from easily pushing it out. Maintaining proper drainage near the driveway also discourages nesting, as ants are drawn to moist environments. Ensuring downspouts direct water away from the pavement and keeping soil or organic debris clear of the edges reduces the area’s appeal for colony establishment.