Anatomy of a snow-storm clean-up

By Michael Trusiak

BATHURST – Winter can be an icicle-in-the-side for many of Canada’s municipalities, especially for ones on the east-coast.

How much money for the winter budget?  Do we have enough plows?  And where to put all that snow, are common conundrums for cities and towns.

On the other hand, you may not have much of a winter at all, thanks to the unpredictable nature of old-man-winter.

You might have a wet winter, a conservative one or it could just be a full blown snowpocalypse.

It also takes a tremendous amount of time, recourses and planning to coordinate a winter-storm clean-up.

Either way, towns like Bathurst along with their city workers must clear the streets, sidewalks and thoroughfares for people and the municipality to go about their daily jobs.

"Winter is coming!"

Todd Pettigrew is Bathursts’ city engineer and along with fleet manager Ron Scott are tasked with planning and coordinating clean-ups after storms.

The first thing that happens before the first snow flake falls is of course, checking the weather.

“Right off the bat we have what we call an emergency response,” he explains.  “We have a foreman assigned 24 hours a day for a week at a time who’s on call and monitors the situation of snow fall during the evening and during the night, but during the day it would be the foreman Ron who’d be working on that.

“The second the roads begin to get slippery, we have ‘emergency routes’ that (we have to plow) with our three plow trucks to keep those ‘emergency routes’ open throughout the storm.”

Each plow is assigned to clear one of the two routes used for emergency responders like police and ambulance as well as important residential, commercial areas like schools and the city centres.

One section is divided into 60 kilometres of roads while the other is made up of approximately 70 kilometres.

“So they can start immediately, depending on the storm, whether it’s freezing rain or when it starts to build up or when we know there’s going to be a storm, there are different factors that are looked at so that our salt trucks, plow trucks do these routes one and two.”

As Scott mentions though, that amount of infrastructure takes time to clear.

“And that takes us usually 4-5 hours from where he (the plow driver) starts to when he gets back to that point,” said Scott.

“But these things will run as long as it’s safe and visibility is good,” Pettigrew reiterates.  “If visibility is bad we’ll have to take them off the road.”

The other sections and sub-divisions that snake in and around Bathurst are then left to the eight, outsourced contractors to clear.

“There are nine plowing routes throughout the city and once 3 inches of snow has accumulated or if we know it’s going to be a big storm, we’ll call in a contractor, but […] it depends on a lot of different situations,” says Pettigrew.

When to call in the contractors, as Scott explains, is up to them.

“We monitor the weather because it might say it’ll start at midnight,” says Scott.  “But only starts at two, three in the morning, so we monitor and make our judgment call then.”

Eight of the nine contracted routes go to independent contractors in and around the Bathurst area, but public works is in charge of clearing one of the nine.

 “And we don’t stop plowing until the storm is over and everything is cleaned up.  If they do their run and it’s still snowing they’ll do it over again.

“Normally those runs will take up to 8-9 hours (each).”

As Pettigrew points out, the reason it seems to take so long to plow each route is because the trucks can only plow to the right side of a curb.

What to do with all that snow

Once the road and sidewalk crews have plowed the snow into banks along the sides of the streets and the storm has stopped, the city calls in their snow removal team.

Snow in major downtown sections like King Street and St. Peters has to be trucked away within 48-hours and usually done by one night shift working from midnight to 8:00am while everyone is off the road.

“We take the sidewalk plows and plow it out on to the street then the loaders with the plows come and plow the roads and then the blower comes and loads it into the trucks,” Scott explains. 

The city owns and operates only one snow blower that attaches to a front-end loader, but devours snow banks at an insatiable rate.

“Actually its 2700-tons an hour so you can load a tractor-trailer in about 18 seconds if there’s lots of snow,” says Scott.

 “We usually hire five trucks, five tractor-trailers to haul the snow and we have a snow blower and we are the ones who remove the snow other than the trucks.”

Then comes the hundreds-of-kilometres of intertwined secondary roads, subdivisions and sidewalks that also need to have their banks removed.

This is without question the most time consuming part of a winter storm clean-up in Bahturst and it can be doubly true if there are multiple storms within a couple of days.

Two-weeks ago that was the case.

“Last storm we had about 67 cm plus the snow from the previous storm so we had over 100cm,” Scott recalled.  “It took us a whole week, running 16-hour days, two shifts, running midnight-4pm for the snow to be removed.”

Streets without sidewalks usually have the tops of their banks pushed back by way of the plows’ side-blade raised 3-feet off the ground, a term referred to as “benching”.

“The most important part for us is we have to have some place to put the snow,” Pettigrew says.  “We have to make sure there is enough room to push the snow back, otherwise the roads will get narrower and narrower.

“Plus with freezing conditions if it freezes you are not going to be able to push that snow back.”

A salty situation

Public works is always looking for more efficient ways to combat old-man-winter.

One of the most important aspects of keeping the roads clear is of course road salt.

Bathurst and other municipalities have been using salt coated with a specific mixture of brine (concentrated solution of salt in water) to help reduce the amount of road salt used on streets by 33 percent according to Scott.

“We have a mixer back at our salt dome that mixes it,” explains Scott.  “The water runs through the mixer and when the water gets to 23 percent, then it stays in the holding tank, then we pump it into our trucks into these tanks.”

This 23 percent salt-water mixture helps prevent the bonding of snow-ice to the road surface.

Composite tanks which hold the brine are mounted to each side of the plows and are connected to the salt spreader via a series of hoses.

The tubes then spray the salt just as it falls from the spreader which is synchronized with the trucks’ drivetrain to better control the amount of salt falling onto the road.

The solution is only effective however at melting snow in a narrow temperature range below freezing, known as the eutectic point.

As Pettigrew explains (see phase diagram), it has more to do with science and chemistry than simply quantity.

“Now say I move to between 25-30 percent salt solution, it drops the freezing point back up to 0 degrees.

“So that’s a fine line where you don’t want to add too much, because it’s not working.  And people say ‘add more salt, add more salt,’ well, adding more salt […] actually makes it worse.”

The solution can also be added to the road surface up to 48-hours before even the first snowflake falls from an incoming storm, so when the snow hits the ground, it just melts and doesn’t freeze.

How much snow is too much snow

Winter is a natural part of life in the Maritimes.

It just so happens that we’ve become very good at dealing with whatever it throws at us, thanks to more advanced technology, a lot of planning and capable people.

But winter still manages to get the better of us sometimes, even the ones charged with cleaning it up.

“Ahh, the worst one for me was about 4-5 years ago,” recalls Scott.  “It snowed mostly during the night and visibility was nil, like you just couldn’t see a thing.

“It was probably about 60cm but the wind blew so hard during that storm that we stopped all the plows.

“We even had a contractor come by here (public works building) and one of the guys had to walk out there and find him and lead him into the yard with a flash light.  Visibility was nill everywhere!

“And we did have an ambulance call during that and one of the plow trucks found their way through to the ambulance to a seniors home to get that person out.  That was the worst I’ve ever seen.”

Pettigrew also remembers it, “That was my first-year.”

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