TulsaPeople / July 2010 / A “hole” lot of repairs

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A “hole” lot of repairs

Thanks to continual freezing and re-thawing during the winter months, 2010 may already be the worst year for potholes in a decade. Here is how the city is working to fix them.

This may be remembered as The Year of the Pothole.

While there are no handy statistics to prove any pothole records, “This is the worst I’ve seen,” says Darren Stefanek, manager of street maintenance for the City of Tulsa. “We haven’t seen a year like this since 2000.”

From February 2009 through the end of January this year (the latest figures available), Tulsa logged 2,108 pothole calls, filled 90,330 potholes and used nearly 49,000 square yards of material. Another 22,500 potholes were fixed between January and April.

Repairs went about $400,000 over the $325,000 maintenance budget.

Most of that was during the period from about Christmas 2009 until this spring.

In that time, Stefanek says, streets “had an incredible amount of damage.”

His 13 three-man crews can fix about 100 potholes a day. An ordinary one takes about seven minutes; bigger ones take up to two hours.

Three factors affect potholes: age, maintenance and weather.

Tulsa streets are old. Most were built in the 1950s to 1960s or before; many date to the early developments, including building additions and neighborhoods, from about World War I through the 1930s. In the heyday of development, from roughly the end of World War II until about 1970, developers platted large areas and sold lots to individuals or builders.

In Tulsa, these developers were responsible for building streets but not for maintenance once streets were completed and turned over to the city.

Even “new” streets — such as four-laned South Memorial Drive, South Sheridan Road, North Harvard Avenue and 71st Street — are a decade or more old. The older the street, the more cracks and crevices it will have for potholes to start.

Over the decades, Tulsa has also cut back on street maintenance, as revenues and budgets fell. When money is tight, maintenance typically is cut or deferred.

Finally, the weather. Last winter resulted in snow and ice on the ground for three or four weeks at a time, with regular freezing and thawing.

It is the freeze/thaw cycle that is deadly. Water seeps into a tiny crack or crevice and freezes, expanding and forcing the crack slightly bigger. The next freeze pushes it more. Eventually a chip breaks off, making a bigger hole. And in days, weeks, months — or sometimes years — that crack becomes a pothole.

“Once water gets in, it’s just a matter of time before it breaks,” says Chris Cox, the city’s transportation rehabilitation manager.

Tulsa, and Oklahoma, are not alone.

“We’re all pretty much in the same boat,” Stefanek says of comparisons to other cities.

An Internet check shows that many cities in the Midwest and Southwest maintain pothole operations like Tulsa.

Broken Arrow, Jenks and other suburbs shared this year’s street woes but likely on a lesser scale because Tulsa has more old streets and more traffic.

And some of the worst and most noticed holes were not in city streets but on state highways, Interstate 244, U.S. 75 and U.S. 169. Interstate 44 was largely exempt because much of that road has recently been rebuilt. The state makes all repairs on highways.

The situation “is much worse in this part of the country,” says Tommy Harrison of APAC, one of Tulsa’s asphalt suppliers, who has been dealing with this since 1970. The Deep South doesn’t have that much freezing and the far north tends to stay frozen; “it’s the freeze/thaw” that destroys streets, he says.

Stefanek’s crews are still fixing potholes and will be all summer.

There are three categories of repair:

Smaller and more surface holes are just patched with hot-mix asphalt (a mix of 3/8 inch gravel, emulsified asphalt and sand). This will last a year or two — or even longer, depending on weather and traffic.

Larger and deeper holes are patched temporarily and then referred to the city’s street maintenance contractor. This company, for the past several years Becco Construction, will dig out the hole and adjoining street, fix the subsurface and then repave it with asphalt. These repairs typically are marked by large squares or rectangles. Last year this work cost $420,000 on non-arterial streets, mainly residential, and $650,000 on arterial.

Streets with major pothole damage are referred for capital improvement reconstruction. This may take a year or two or more to schedule. Money for this generally comes from bond issues or special sales tax elections. In the meantime, potholes will be patched as often as necessary.

Crack-sealing is another repair option and is preventive because it keeps water out of the crevices. And even warm water can cause potholes — in fact, they occur in tropical areas — if it penetrates into the base below the pavement. For many years, Tulsa’s street department had a crack-sealing unit, but cuts gradually reduced its force and eventually eliminated it.

Now the city contracts with Pavement Conservation Specialists. This year it will seal cracks in about 43 miles of arterial streets and 91 miles of non-arterials, at a cost of $1.10 per foot for arterials and 45 cents for residential. Arterials generally are concrete and patched with silicone, which is more expensive than the asphalt/rubber mix used on asphalt streets.

Crack-sealing and potholing are largely decided by visual checks. But if a caller reports a pothole, a crew will fix that and then look in that same area for more to patch.

If the city had a larger crack-sealing staff, “it would be very beneficial,” Cox says, but this is a question of money and manpower.

“Like all cities, Tulsa will always have to respond to the effects of this constant deterioration and the resulting damages,” Stefanek says.

Former Mayor Kathy Taylor’s Fix Our Streets initiative will help some. But that is a long-term project on a limited number of streets.

Concrete surfaces are more durable than asphalt but more expensive to build. And even concrete is subject to cracks, mainly at joints and edges.

Also, any roadway has a finite life span and requires maintenance, says Matt Liechti, lead engineer for transportation design for the City of Tulsa Public Works Department. Roads are designed for 20- or 30-year life spans but even then require maintenance, just as a new car requires oil changes and other maintenance.

And no matter how or when it is built, it is still subject to the weather.

“Moisture is the enemy,” Liechti says.