WILLISTON, N.D. -- When the oil boom started in North Dakota, the roads were the first thing to give way.
Mountrail County, where some of the first Bakken wells were drilled, has about 200 miles of paved county road. The other 1,100 miles that the county maintains are gravel, and they were no match for the influx of heavy oil field equipment. The trucks tore up the gravel roads, leaving the county government struggling to keep up with maintenance at a time when North Dakota is awash in oil revenue.
"Nothing like this has ever happened before," Greg Boschee, a Mountrail County commissioner, said in an interview. "The rocks, after you pound them with trucks, are just dust."
North Dakota pumped 874,000 barrels of oil a day in July, accounting for almost one of out every eight barrels produced in the United States, according to state and federal figures. About 85 percent of the state's oil came from four counties in the northwest corner of the state: Mountrail, Williams, McKenzie and Dunn.
Together, those counties have a land mass bigger than New Jersey. Before the boom hit, they had been slowly losing population for almost 50 years, down to a combined 40,000 residents in 2010.
Dunn County had fewer than two residents per square mile in 2010 -- meaning it was less densely populated than when the U.S. Census Bureau declared the American frontier closed in 1890.
In McKenzie County, ranchers used to drive cattle along the county roads.
"That way of life is kind of gone," said Ronald Anderson, chairman of the McKenzie County Commission.
Before the oil boom, a typical gravel road would handle fewer than 50 vehicles a day -- usually pickup trucks and small farm and ranch trucks. Typically, the county had to grade each road every two weeks to keep them in shape, said Dennis Nelson, the Williams County road superintendent.
Today, some county roads see as many as 1,000 vehicles a day, according to a state study.
"Now, we should be doing every road daily and it doesn't work like that," Nelson said.
For N.D., isolation poses extra challenges
Across the United States, the boom in shale drilling has led to similar complaints. Pennsylvania imposed an impact fee on drillers in the Marcellus Shale to pay for roads in the counties affected by drilling. In South Texas' Eagle Ford Shale, the state Department of Transportation has suggested converting paved roads to gravel roads because the state can't afford to repave them.
North Dakota may be the most extreme example because the Bakken oil boom happened in a sparsely populated corner of the state. Apart from the state highway system and a few small cities, about three-fourths of the roads in the most productive parts of the Bakken Shale are two-lane gravel tracks built for farm and ranch traffic.
Unconventional fields like the Bakken require a constant cycle of drilling to unlock the oil trapped in the rock, which means more traffic. More trucks arrive when the wells are hydraulically fractured -- a process that involves breaking up the rock with a high-pressure mix of water, sand and chemicals. There's an extra influx in areas where the water has to be trucked in.
And in North Dakota, the lack of pre-existing pipelines and the obstacles to building new pipelines can mean even more trucks to haul the oil and wastewater away from the wells.
The county governments and North Dakota's Legislature have funneled about $523 million into the oil-producing region during the current two-year budget cycle, according to an analysis by the North Dakota Association of Counties. About half the funding, $282.9 million, comes from the state's gross production tax on oil. Another $169.1 million came from a one-time appropriation aimed at fixing infrastructure in the oil-producing region.
Counties and local governments are trying new methods to stabilize and strengthen their roads, and the state Department of Transportation is widening and reinforcing state highways through the area.
At the same time, state and local officials agree that they'll have to keep putting in the same kind of effort -- and spending roughly the same amount -- to make sure the roads don't fall apart. A study by the Upper Great Plains Transportation Institute estimates it will take $348 million every two years to maintain the oil-producing counties' roads. And with as many as 32,000 new oil wells projected to be drilled over the next 20 years, even that may not be enough.
"We're trying to maintain and we're not keeping up," said Nelson, the road superintendent in Williams County.
A typical shale well in North Dakota requires 1,150 truckloads to bring in the equipment, sand and water for drilling and hydraulic fracturing, according to the transportation institute study. Add in the return trips, and that's 2,300 truck trips per well.
Plus, about 25 percent of the sand and water trucks are overweight, the transportation institute estimated, using records from the North Dakota Highway Patrol.
'You just grin and bear it'
The results are easy to see across oil country.
Frances Olson, who lives outside Watford City in McKenzie County, lives on a gravel road that serves a string of oil wells and is also the main route to a couple of gravel pits. The county recently rebuilt the road, but the repairs didn't last.
"Now it's in worse shape than before," she said. "You just grin and bear it."
In neighboring Dunn County, Brien Dennis used to wipe dust off his pickup's windshield every morning. His ranch house is a quarter-mile from the nearest road, but the constant parade of oil field trucks sent a cloud rolling onto his property every night, not to mention tearing up the road.
"They'd fix the road and blade it and a day later it was potholes again," Dennis said.
The dust subsided when the drilling traffic moved to other areas. That allowed the county to treat the road with magnesium chloride, which reduces dust and holds the gravel in place.
It can cost $7,000 a mile to treat a road with magnesium chloride and as much as $200,000 a mile if the road requires new gravel, County Commissioner Daryl Dukart said.
As the commissioners got used to living with oil production, they started asking oil companies for drilling schedules so they could determine where to direct their road maintenance.
The oil-producing counties have also tried other methods, such as adding cement to the road base below gravel roads, or using products such as Perma-Zyme, a soil stabilizer sold by California-based IEC Distributing LLC. Some have used oil field brine -- which is loaded with salt -- to control dust on gravel roads.
Pipelines hold promise
In his office on the north side of Bismarck, the state capital, Mineral Resources Director Lynn Helms said road construction is part of the "whack-a-mole" game he and his staff play to keep up with the interrelated issues the Bakken has produced.
Pointing to a map of the Bakken formation, Helms said most of the well sites in the field line up in a grid, since most of the area was leased in similar-sized blocks.
"You can identify where the well corridors are -- those roads could be rebuilt to keep the maintenance costs down," he said.
Connecting wells to pipelines could slash the number of truck trips, particularly if the operators could add separate lines to bring in fresh water and dispose of wastewater, according to a slide presentation Helms published last month.
Unlike in Texas and other oil-producing states, oil companies in North Dakota can't condemn private land for a pipeline, Helms said. That has left companies negotiating each pipeline right of way with landowners.
About 95 percent of the oil in Williams County was moved by truck in February 2012, according to the North Dakota Pipeline Authority. By September 2012, that percentage had dropped to 75 percent, and the percentage of oil transported by truck fell in McKenzie and Dunn counties, too.
In Mountrail County, though, the percentage of oil moved by truck actually increased to 59 percent from 55 percent during the same time frame.
Back in Dunn County, the pace of drilling has slowed, at least temporarily, Dukart said. Most of the county was leased for oil development at the same time, and oil companies rushed to drill in 2009 and 2010 before the leases ran out. Now, the talk is of "infill drilling," when operators return and drill more wells on the same site.
That gives the county time to fix roads and plan other strategies, like paving the routes that get the most oil field traffic, Dukart said.
Turning his four-wheel-drive pickup onto one of those highly impacted roads, Dukart rattled off its history. It's the main route between the paved state road, Highway 200, and the oil wells on the west side of the Killdeer Mountains. It was handling 350 to 400 trucks a day until the recent slowdown. The constant traffic eroded the top and spread the shoulders out like a flattened toothpaste tube. The county rebuilt it last year.
In its new state, the road may last three years.
"It depends on how many pipelines come in the meantime," he said.