From frostbite to snowdrifts, northern cities face a flurry of winter garbage collection challenges. In many cases, an ounce, or rather a few quarts, of prevention throughout the cold season can mean the difference between maintaining normal collection schedules and having a frozen fleet stalled in the garage.
October is a good month to begin assessing the fleet - checking antifreeze and changing oil.
Ray Wald, shop foreman for the city of Minneapolis Solid Waste and Recycling Department, tests each vehicle in the city's 86-piece fleet for antifreeze concentration levels using a refractometer. This is performed well before conditions start dipping below freezing because Minneapolis' winter temperatures can fall to a deathly cold minus 80 degrees with the windchill.
In addition, every vehicle's diesel fuel mix is changed to a 60/40 blend in the fall. Diesel fuel can develop a wax build-up in the winter if special additives are not used, Wald explains.
Minneapolis begins switching to the blended fuel on October 1, even though the city doesn't usually reach freezing temperatures until mid-November.
"We like to allow for those trucks that aren't used as often," Wald says. "That way, we know every vehicle has a full tank of winter fuel by the time the cold weather hits."
Since becoming shop foreman two years ago, Wald has retrofitted several engine block heaters, and has required them on all new vehicles purchased by the city, giving his all-diesel fleet a jump-start on the freeze.
Equipment in general doesn't work as efficiently in freezing conditions. From breaks to hydraulic lifters, sub-zero temperatures slow everything down. Periodic equipment inspections can help alleviate many in-service malfunctions and the hours of labor required to fix the weather-induced problems.
"It's no fun unfreezing break pads," says Joel Grunwaldt, solid waste director for the municipality of Anchorage, Alaska. His department conducts regular inspections on air dryers to prevent break pads from freezing.
Frozen and slow-moving hydraulic lifters are another winter weather complication. Hydraulic fluids are switched to a special winter mix to combat freezing, Grunwaldt says. Even so, hydraulic machines will respond more sluggishly if they are not properly primed before use.
In Minneapolis' case, trucks are kept warm overnight in heated garages, which allows crews to start operating hydraulic machines at peak performance sooner in the winter work day. "We keep the majority of our trucks inside," Wald says. "It helps hurry up the warming process. With any hydraulic drive, if a truck sits overnight in sub-zero temperatures, the oil gets thicker, which in turn slows down the hydraulics."
Many refuse truck operators can make the mistake of pushing the performance of their hydraulic lifters before the oil has a chance to warm up, which can lead to blown-out hoses, Wald notes. This is because colder oil, which has a higher viscosity, is forced through systems.
Consequently, fleet managers without the luxury of heated garages should allow hydraulics time to properly warm up before commencing collection routes, Wald recommends. There is a tendency for sanitation crews to attempt to work at a summer pace during the winter months, pushing machinery past cold-weather performance capabilities, he says.
Susan Young, director of solid waste and recycling for the city of Minneapolis, is just as concerned for the well-being of her crew braving the elements as she is concerned about Minneapolis' fleet.
"We haul in all weather conditions from minus 80 degrees to as hot as 105 degrees, so we try to educate our staff," Young says. Over-exposure to harsh weather is a major concern during the winter, she says. She's seen cases ranging from common hypothermia to frostbitten eyelids.
To prevent over-exposure, Minneapolis collection crews are encouraged to take frequent breaks during harsh weather. Also, a buddy system better ensures early detection of exposure-related health problems.
Residents also need to cooperate in harsh climates. Collecting garbage in the winter often requires scaling snowplow-created black snow berms to reach solid waste carts. Many cities have ordinances requiring customers to clear a path to trash containers. "It's a joint effort between our crews and customers," Young explains.
Work-related injuries can become a concern when crews attempt to service inaccessible carts, she continues. In Minneapolis, if the problem persists beyond a week, customers are sent a warning letter. If the problem has not been corrected by the third week, the city shovels out a path, hauls the garbage and bills the violating customer accordingly.
The Milwaukee suburb of West Allis has a similar policy. A city ordinance requires a clear path to refuse carts within a two-hour period after each snow storm, says Jeff Jender, West Allis' sanitation supervisor.
"If it becomes a problem, we'll first send them a notice, then a letter giving them seven days [to comply]. Then, the police department issues a citation," Jender says. "If the garbage is piling up, we'll clean it, but charge an additional fee for the cleanup."
However, West Allis is capable of clearing a path to the garbage, Jender says. Each of the city's 20 refuse trucks is equipped with a quick-hitch snowplow. Combined with its fleet of dump trucks, also equipped with plows, West Allis is ready for snow.
While dump trucks tackle the main roads with plows and salt, front-end loaders equipped with V-blades clear the city's alleys. More than half of West Allis' residential zones have alleys, Jender notes. While all of the city's refuse trucks plow snow as well as collect garbage, none collect and plow simultaneously. "The plows are always off when we're collecting," Jender says.
Despite the weather, customers must be serviced, haulers say. When the Alaska Public Utility Board issued a residential collection tariff to Anchorage Refuse, a division of., Raleigh, N.C., it was with the stipulation that Anchorage would service any resident regardless of the amount of snow or the mountain elevation.
"We're the only certified residential hauler in the area," explains Kurk Duncan, Anchorage Refuse's district manager. "Our residential service area takes us into the foothills and way up into the mountains, and we're required to service them all, regardless of terrain."
The climatic challenges, combined with rigorous terrain, require special refuse trucks. Not able to buy trucks off-the-rack, Anchorage's fleet includes several four-wheel drive vehicles with custom-built Freightliner chassis. In addition to four four-wheel drives, Anchorage Refuse equips its vehicles with tire chains.
"It gets pretty icy in February," Duncan says. In addition to avoiding slippery black ice on the road, sanitation crews also face trying to empty frozen blocks of solid waste out of refuse carts during the winter.
"You haven't lived until you try busting frozen garbage out of a 90-gallon, upside-down cart," Minneapolis' Young says. The problem starts when people bring their wet garbage out of their warm 70-degree homes. We ask our customers to place all their garbage in secure bags."
The city of Anchorage and Anchorage Refuse teamed up 10 years ago to solve the problem of waste freezing to the sides of transfer station roll-off units. Frozen garbage literally is chipped off the sides of containers, using front-end loaders equipped with 15-foot sections of steel I-beams that serve as giant ice picks. Known in Anchorage as "stingers," these ice picks are used to chip frozen garbage out of everything from compactors to open-top roll-offs.
"Once you break it [frozen solid waste] loose in a few places, you can usually dislodge it," Duncan says.