How four rock quarries and a fleet of versatile equipment keep road maintenance costs low in northeast Iowa.
Workin' The Rock Quarry
You might think that maintaining graveled roads in farm country is no big challenge - but it is. For example, Fayette County, Iowa, maintains 920 miles of two-lane graveled roads, and they take a beating from farm equipment, semi-trailer rigs, and passenger vehicles. Tons of gravel are pushed into the road base or are lost as dust behind traffic every year.
As a result, all 920 miles must be fully resurfaced with limestone aggregates at four-year intervals. Fortunately, Fayette County officials have access to limestone at four local rock quarries. And unlike most Iowa counties, Fayette operates its own 250-ton-per-hour rock crusher that rotates annually among the four quarries. "Having our own crusher saves us at least $540,000 a year," says county engineer J.D. King. "That's huge for us, because our secondary road maintenance budget runs about $5.3 million to $5.5 million per year. We can obtain and crush limestone aggregates for less than $2 per ton, including all labor and equipment. If we had to buy that rock commercially, it would cost us $5 per ton. We crush about 180,000 tons of rock every year, so that $3 per ton of savings adds up quickly."
Keep 'em Moving
In the summer, the crusher runs four 10-hour shifts per week. Downtime is a dirty word, because most of the aggregates are hauled directly from the crusher to an ongoing resurfacing project. It's important to keep the trucks moving. That's why Fayette County relies on a Volvo L220E wheel loader, fitted with a 6.5-cubic-yard bucket, to charge the crusher. The county bought the loader a year and a half ago as a used machine with 1,660 hours on it - and has since added on more than 2,100 hours. "We really like the fuel economy on this loader," says Tim Weston, quarry foreman and primary operator. "It only uses about 55 gallons of fuel per day, and that's eight or ten fewer gallons than a smaller loader that we had before. The loader has nice breakout power for digging into the rock pile," says Weston.
"It's comfortable, and the air conditioning works great, which is nice in the summer. And the machine has a 350-horsepower engine, which gives it good power coming up the ramp out of the quarry." King says the county has traditionally received good service from their Volvo dealer, which was recently purchased by Scott Van Keppel LLC. "We have had good service from the previous dealer, and we expect the same high quality of service from Scott Van Keppel."
At a time when many public works agencies are outsourcing more jobs than ever, King and Fayette County officials take pride in doing things themselves. The county maintains a $6.5 million fleet of equipment, including two Volvo EW170 wheeled excavators, the big Volvo loader, and a Volvo EC290B crawler excavator. The fleet also includes 12 tandem-axle trucks, four bulldozers, and 12 motor graders. "We do a lot of our own grading projects," says King. "We've cut down hills and extended the foreslopes along roads, stripped overburden for the quarries, helped build quarry access roads, and performed the grading for culvert extension projects."