Road workers still seeking perfect solution to potholes

A motorist dodges a pothole Friday on Connecticut Street near 15th Street. After a long, hard winter, city officials and motorists are seeing a lot of them and figuring out how to fill them or avoid hitting them.

Pothole hot lines

To report a pothole for repair:

• In Lawrence, call the city’s Pothole Reporting Line, 832-3456, or fill out a form online, through the Public Works page at LawrenceKS.org. Crews attempt to address problems within 24 hours.

• In Eudora, call 785-542-3100. In Baldwin City, call 785-594-6907.

• On state highways, the Kansas Department of Transportation takes reports based on their county locations: Douglas, 785-528-3128; Johnson, 913-764-0987; Shawnee and Jefferson, 785-296-2291; and Leavenworth and Wyandotte, 913-721-2960.

Don’t bother asking Tom Orzulak about any breakthrough treatments for pothole repair, about whether he’s come across any high-tech materials or ultra-reliable methods for plugging those most stubborn of pavement problems.

The dream — call it the No-Fail Permanent Pothole Packer and/or Preventer — remains far off the map.

“I’ve been working on that for 30 years,” said Orzulak, street division manager for the city of Lawrence. “If I knew that, I’d be in Aruba enjoying all my money. But I’m not.”

No, he’s not. Nobody is.

Fixing a pothole in the variable weather conditions of the Midwest means adhering to essentially to the same process and materials that have been the industry standard for decades:

• When it’s cold, and potholes appear as fast or faster than they can be filled, crews quickly pour a temporary patch of “cold mix” pavement into potholes. Such repairs may last only a few days or few weeks, but can keep traffic moving smoothly and safely until warm weather arrives.

• In relatively warmer and drier conditions, crews often turn to “hot mix” pavement: a mixture of asphalt, rock and sand that is mixed together and maintained at between 230 and 310 degrees. Crews carefully “square off” the sides and bottom of a pothole, to enable a strong bond between the fresh material and existing road. The material then is compacted to reduce the chances of problems arising again.

Unfortunately, such repairs often don’t solve the problem that caused the pothole in the first place.

“It’s water in the subgrade,” said David Darwin, a distinguished professor of civil, environmental and architectural engineering at Kansas University, whose research focuses on extending the life of pavement on bridge decks. “Water expands when it freezes. Then you have trouble.”

It’s the dreaded freeze-thaw cycle: Water seeps under the top layer of pavement; water freezes, expanding enough to push the road surface upward; when the ice melts, the pavement drops back down again, eventually crumbling under the weight of passing traffic.

Darwin, who served in Vietnam, recalls working in areas with heavy rainfall. While the areas didn’t suffer from freezing, the practice of keeping things dry still held up.

“The roads I built in Vietnam, they’re still there,” he said. “The whole thing is to have really good drainage. You’ve got to keep the water out of the subgrade. It’s easy for me to say, but not all that easy to do.”

Researchers have created synthetic asphalt, come up with special strengthening fibers, and even equipped spray machines to apply asphalt pavement in a uniform manner.

“There’s been a ton of research that’s gone into filling potholes,” said Rex Fleming, project engineer for more than $150 million of reconstruction work along the Kansas Turnpike through and east of Lawrence. “But you still need to get out there with equipment, clean the hole out, dry it out and fill it in. It’s still the same work: Get out in traffic and get it taken care of.

“Hopefully somebody will find that magical answer for us.”

Terese Gorman, engineering division manager for Douglas County, said the best way to fix potholes was to prevent them in the first place. And the best way to do that is to build roads better in the first place.

“We’ve learned a lot about the subgrade and the moisture over these many eons of engineers,” Gorman said, who noted that soil treatments during construction can extend the lives of roads.

Orzulak, who started dealing with potholes back in 1980 while working with the Pennsylvania Department of Transportation, said roads should be expected to last 20 to 25 years.

While many governments employ various strategies to put off reconstruction for another decade or so, the end really is inevitable.

Turns out the only surefire way to seal potholes for good, or prevent them in the first place, would take a rather disruptive force of nature.

“If it’d get cold and stay cold,” Orzulak said, “we wouldn’t have potholes.”