Twin Cities road crews' refrain: plow, patch, repeat

Wondering if the potholes you're driving into or veering around each day will ever get fixed?

Blame the weather.

Part of the delay in the normal patching this time of year is the unusual yo-yoing between snow and normal April weather, say pothole fighters across the metro area.

"What's changed for us is that it stopped snowing and then started snowing, and then stopped snowing and started snowing," said Mark McLarty, a maintenance foreman for Hennepin County.

On Tuesday, for example, "Priority 1 was getting the snow off the roads," he said. "Tomorrow, we'll have every patch truck on the road."

With what should be a warmup headed to the Twin Cities later this week, crews will be scrambling to get caught up on the annual patching chore.

In the meantime, Minneapolis has been relying on about a half-dozen crews on duty responding to complaints from motorists even though the city's street maintenance supervisor judges this to be the second straight spring with fewer potholes than the norm.

Weather is one factor in each spring's potpourri of potholes. But increased spending has helped to upgrade some of Minneapolis' worst streets. Downtown streets have gotten a federally assisted shave and topping with fresh paving. Some streets such as Riverside Avenue and parts of Nicollet Avenue have been reconstructed.

Now one of the city's more notorious sections of parkway is nearing a renovation. Starting Monday, West River Parkway will be blocked between S. 4th Street by the West Bank campus of the University of Minnesota and Franklin Avenue, ground down to a depth of 7 inches and repaved. It's a section where southbound cars have been known to veer into the oncoming lane to avoided the heavily patched and potholed pavement. Bikers also find weaving through the stretch a choice between risking a bent rim or a rattling ride.

Just ask Sarah Dietrich of the Longfellow neighborhood. Last Thursday, driving downtown in a thick snowstorm, she plunged her low-slung Prius into a pothole she described as at least 8 inches deep. That dislodged the lower grille of her car, which is in the shop to be checked for further damage.

She normally takes a faster route, but figured the parkway would be better during a snowstorm. She went back the next day to photograph the pit, and saw so many motorists cratering that she moved a nearby warning sign and placed it in the hole.

"I saw people in the middle of the day doing what I did over and over and over," she said.

Cities have been alternating between deploying snowplows and pothole-patching crews.

One problem this year, according to Dave Hunt, spokesman for St. Paul's Department of Public Works, is that plowing snow after some patches have been laid can rip them apart. "Normally we wouldn't be plowing after we patch," he said.

St. Paul fields at least a dozen three-person crews when they're not diverted to plowing snow and salting at least some roads during the late snowfalls.

Hennepin County has three dedicated patching trucks that keep asphalt warmer and more pliable because the bed is enclosed, unlike dump trucks the county also sends out with patching mix. There's also another unit that can spray a mix of asphalt emulsion and rock into smaller potholes.

"It's set up within minutes," McLarty said.

"It was a frightmare," said Jeff Spartz of Eagan, who drove the section recently. "No one was going over the speed limit, I can assure you of that."

The parkway paving program sometimes needs to mill down only 2 inches of spalling pavement in order to lay fresh blacktop. But for this parkway, workers will mill down a full 7 inches, which may take them into virgin soil.

That's based on what Kennedy said crews have found in other parkway locations. The parkways, built in the 1970s, were supposed to have 7 inches of paving over a gravel base. But often that's not what crews are finding. Good road building practice lays paving atop a thick base of gravel so that roadway subsurfaces can drain. That keeps the freeze-thaw cycle from heaving pavement. It's particularly surprising that such a base is absent given that some sections of parkway run on unstable peaty soils near lakes or swamps.

Spartz was on the Park Board when the current parkways were built but said he was surprised to hear of the skimping on base, a decision that he said sacrifices the long-term durability of a roadway. But motorists will see a better surface soon.

"They'll love it when it's done," Kennedy said.

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