Really cold temperatures during the most recent snowstorm have prompted Auburn’s Public Works department to consider new strategies to keep the city’s roads safe.

When a winter storm hits, the city’s road crews discuss how to tackle road maintenance, which almost always includes the use of salt.

But during the last storm, from Jan. 25-26 when 17 inches fell in Auburn, road temperatures were too low to use salt, which set city staff up for a difficult few days of road maintenance that included a slick Goff Hill on Court Street, snow binding to pavement, and fluffy, light snow that was difficult to clear, Public Works Director Scott Holland said during the City Council meeting Monday.

To date, the city has used 3,500 tons of salt, roughly 80% of what it budgets yearly, according to Public Works Deputy Director Adam Stevens. It takes about 150 tons to load all city plow trucks, and sometimes drivers are making two or three applications of treatments to the roads per storm, depending on the weather. If storms continue, the city will likely exceed its yearly salt budget.

When determining how much treatment should be applied, staff go by the road temperature, not the air temperature, he said.

When road temperatures are above freezing, they do not use any treatment when they plow. When road temperatures are between 28-32 degrees Fahrenheit, they use 200 pounds of rock salt per lane mile; when temperatures are between 15-20 degrees they use 400 pounds of rock salt per lane mile. When rock salt is used, drivers will also spread 8-10 gallons per ton of salt brine.

When temperatures are below 15 degrees, drivers do not use any salt, Stevens said, adding “we’ll just leave it and scrape it.”

Calcium chloride is a product effective at clearing icy roads below 15 degrees, but because of its high cost has not been something the city has turned to. That thinking may change. Salt brine — a mixture of water and salt — costs 15 cents per gallon; calcium chloride costs $1.87 per gallon, according to Stevens.

Sand is used for traction in certain areas, including hills and intersections, but during the last storm the sand packed and bonded with the roads in some places, making it ineffective, he said.

The cold storm hits

Storm number 24, as the city called it, produced snow of a different consistency than higher-temperature storms, Holland said. When the storm struck Jan. 25, road temperatures were below 15 degrees, which is too low for salt to be effective. So Public Works just plowed, which kept roads in fair condition for most of the day.

However, the snow that accumulated Tuesday night seemed to be a bit different than the snow that fell Monday, Holland said, and because it was still too cold to use salt during the overnight hours, the snow bonded with the road in some areas, despite crews being out and plowing through the night.

From there, city staff battled for several days after the storm to get streets clear.

The city typically budgets enough material and staff time for 20 storms, Holland said. More than 20 storms have occurred this winter, with the city receiving 61 inches of snow so far. The city considers a storm when trucks have to clear snow, or deal with freezing rain, freezing roads or other conditions deemed potentially hazardous.

Tuesday morning, Jan. 26, Public Works used a “hot mix,” which is a ratio of two parts salt and one part sand, he said. It can help in low temperatures to clear roads, but it did not work in the last storm.

“Well, it didn’t touch it. As cold as it was, road temps were down near 3 or 4, there was just no way. We basically put stuff out and it didn’t do anything,” Holland said.

Closing Goff Hill

When Auburn Police Chief Jason Moen drove over Goff Hill that Tuesday morning, he faced some of the worst conditions he had seen there in roughly 30 years, he told city councilors Monday night. He quickly decided to close the hill until it could be treated.

“I wasn’t confident that the motoring public would be able to navigate that hill,” he said. “I’ve had to dive over a snowbank on that hill to avoid getting hit by a car sliding down over the hill in the past, so I made the decision to leave it closed for most of the day on Tuesday, just as a safety precaution.”

Goff Hill can be a public safety hazard when it snows, and it usually takes salt to “bare it off,” Holland said. But Public Works crews were not able to do that Tuesday morning, much to the chagrin of residents who contacted the department to complain.

With very low road temperatures, Stevens, the Public Works deputy director, said he knew the hill needed to be “peeled.” They had an employee working to clear the hill later in the day Tuesday and by 7:30 a.m. Wednesday they were able to get the hill clear enough for motorists.

It was not until Tuesday when road temperatures rose that crews could start treating primary and secondary city roads with salt, Holland said. But when the sun went away Tuesday afternoon it hindered plans.

They focused primarily on treating the high-traffic roads Tuesday, which took three runs using 450 tons of salt per lane mile, Stevens said. Then they focused on the secondary roads Wednesday. Roads seemed to be getting cleared, with higher temperatures helping.

During those several days, Public Works staff worked rotating 16-hour shifts, getting eight hours off between shifts, he said.

There were nine accidents during the storm, which Moen said is low compared to other storms. Two of those accidents involved Public Works vehicles, Holland said.

One of those accidents involved a driver getting between two of the city’s plow trucks, which usually stay together to prevent cars from passing the plow truck and help control traffic in areas with many blind spots, Holland said. Despite complaints from the public, they do that to keep motorists and plow truck drivers safe.

Cold storm takeaways

The city received complaints during that storm that roads outside Auburn were better maintained, Holland said. But state roads often have higher traffic, which helps snow blow off the road and makes treating them more effective. So while some state roads were “bared off,” areas in the city had compacting snow on roads.

There are a number of changes Public Works officials hope to implement possibly by next winter. Those include:

• Creating “Goff Hill closed” signs to be placed on several roads to alert motorists of a detour before they get to the hill.
• Keeping 10,000 gallons of calcium chloride on hand each winter for low-temperature storms.
• Constructing another salt storage shed.

Though the low temperatures of the most recent storm made salt ineffective much of the time, officials are concerned that the city’s salt shed is not big enough to handle a typical winter’s needs. Because it can only hold about 1,000 tons, the city orders salt ahead of any storm it anticipates could be required. Sometimes, however, the city can’t get a shipment in time for a coming storm.

Another storage shed for city property at 67 Kittyhawk Ave. is in the city’s Capital Improvement Plan.

There are no plans to buy calcium chloride this winter, according to Liz Allen, Auburn director of Communications and Community Engagement.