Pothole Patching: Spray-Injection Patching

Nestled in the Litchfield Hills of northwestern Connecticut is a small city that has made eradicating potholes on their streets a year-round activity. Today, the 36,000 people calling Torrington, Conn., home don’t have to spend their driving time dodging potholes.

However, nine years ago, potholes were a huge problem for the city. Everything changed when Superintendent of Streets Bob Lizotte attended an American Public Works Association meeting that year and was intrigued by spray-injection patching equipment on display at the show. “When I got home, I researched the equipment and settled on the Rosco RA-300 spray-injection patching machine ,” Lizotte said.

The pothole patching solution was well received by the mayor and city council, Lizotte said, but the budget was tight and purchase was postponed. In a twist that was good news for the drivers and taxpayers of Torrington, the board of finance was convinced that the patcher was a good idea and the purchase of the pothole patcher was funded.

“In the early years, placing 50 to 60 patches a day wasn’t unusual since we had a lot of catching up to do,” Lizotte said. “Today, we operate the patcher five days a week and probably place about 20 patches per day.” Of course, the city’s pavement management system for upgrading streets on a scheduled basis has helped to eliminate the causes of potholes as the city’s 180 miles of roads, streets and bridges are better maintained and replaced.

The city has two operators trained on the spray-injection patcher . The joystick controls are simple to use. The operator is safe in the truck’s cab during patching and protected from the weather. The only time the patcher stays in the shop is when temperatures are below 20°F, Lizotte said.

Sitting inside the cab of the truck, with blinking lights on the truck’s rear directing traffic around it, the operator can blow the pothole clean of debris with a high-pressure blast of air; spray hot emulsion into the hole to bond the filler with the old surface; fill the hole with a high-pressure spray of asphalt-coated aggregate; and top the patch with a dusting of dry aggregate.

Early on, Lizotte said, the public was a little skeptical with the loose stone final coat on top of the patch, but now it is a fact of life and people are pleased to see the patches since they know they will last.

“What we like about the spray-injection patches is that we can patch 12 months a year,” Lizotte said. “When we used cold patch, we had a crew of six people out on the roadway in winter conditions and they would patch the same pothole over and over. They just didn’t last.” The pothole patcher allowed the city the flexibility to put those people on other tasks.

Maintenance of the nine-year-old spray-injection patcher has been minimal, according to Lizotte.

Torrington’s success in managing potholes has brought other city personnel from New England and eastern Canada to their city to learn more about their program. Looking back, Lizotte said that the pothole patcher was a great step for the city of Torrington. It saves the city money. It allows the city to better utilize its staff. It is safer for the operator placing the patches.