By Cole Parkinson
After previous council requests to look at the history of the Municipal District of Taber’s Dust Mitigation Program, the topic was brought to council chambers.
During the M.D.’s policy meeting on August 7, councillors were given the low down on what exactly the program was and all prior history.
Upon Coun. John Turcato’s request to explore the history of the program, one of his major concerns was the cost.
For 2017, the M.D. reports the annual expenditure for calcium for dust suppression was at $343,000 while they collected $99,000 from residents who participated in the program with 50 per cent of the cost recovered from residential applications.
“People have it in front of their houses and pay half the cost, the second application is done for free but yet all of the ratepayers are paying for it really. The taxpayers are subsidizing dust control in front of other peoples houses and I think they should be paying full costs. If there are two applications being done, they should be paying for two applications,” said Turcato.
Originating in 2012, the program originally started out with only one application per year but the policy was amended in 2013 to include another application due to the dryness in the area.
“Originally it was a 50-50 split on it, it was once a year we would do it,” said Reeve Brian Brewin.
M.D. staff gave council a bit more insight into why the application is made and what the effects are after they are completed.
“In order to fully understand it, you need to have a good general idea of the gravel gradation so the rock size, rock fracture and how that locks together. Loose gravel, if there is an acceleration of a vehicle on that aggregate, it will form a washboard. The ideal gravel surface on a road is tight and compact with proper graduation throughout, not loose rocks everywhere. That’s not what we aim for, that is sometimes what we end up with,” said Craig Pittman, director of planning and infrastructure. “Another important portion of gravel gradation is the amount of plasticity in it, so that’s the amount of clay type substances that will soak up water. When soils soak up water they are going to swell and then shrink back down, thus locking that gravel down even better. Most of our gravel pits are very clean, which means there is not much plasticity in the rocks we are using.”
For the roads though, Pittman highlighted the product used, which helps keep the roads in better shape by drawing moisture from the air.
“It is primarily sandy soils without much plasticity. On one hand, the soil types we have are sandy with a structural barring of sand and the capacity of sand is very strong, the problem is, how do you keep it together?” said Pittman. “Calcium-chloride products, they are high in hygroscopic, which will draw moisture out of the air and keep it in the gravel surfacing in the roadways so that way your roads hold together, that’s the stabilizing portion. That’s why we’re putting it on intersections, to cut back on our maintenance on the washboard areas.”
Staff did state they have moved onto a newer product that yields better results.
While the product is still mainly based on calcium-chloride, it features a different mix that should help road conditions more.
“We’ve moved on from the calcium-chloride onto MG-30. What it is, is calcium-chloride cut with magnesium-hydroxide so it reduces a little bit of the water content and is replaced by the magnesium-hydroxide. It has a more stabilizing effect and has given us better results. The cost point is still in the 50-50 range that we initially set-up,” said Jeremy Wickson, director of public works.
Applications go on roads once in the spring and once in the fall.
As applications need to be made twice a year to be effective, Turcato highlighted the fact the service isn’t a permanent solution for dust mitigation.
“Long-term benefit is zero, by spring it’s gone. You have to start over, it’s like buying fuel. If you took that money and put it toward paving, at least you would have something to show for it. With this, you keep paying and it keeps expiring,” he said.
Since starting the dust mitigation in 2012, there have been some noticeable differences coming from the calcium-chloride.
Coun. Tamara Miyanaga stated she has seen quite the variation on her road since the applications started.
From the product put down on the road, staff say the changes to the roads were expected based on what they were using and how often it was being laid down.
“There is a residual with any kind of liquid you put onto any surface, the residual is penetrating further into the surface. After subsequent years of applications, you do have a way better ‘crust’ on that roadway because you are putting X amount litres of solution on that roadway. You almost end up with a brown pavement,” said Wickson.
Road maintenance has also been helped by the applications as staff have noticed they don’t need to grade as often as they did.
“We’ve found a dramatic change in the amount we have to grade around intersections ever since we started doing these applications through all areas or even off of paved surfaces. If you have a transition between gravel and a paved surface, you do an application right off there,” continued Wickson.
The M.D. also isn’t the only municipality in southern Alberta to use calcium-chloride products on their gravel roads.
“Newell County does it on quite a few intersections and that’s the level of service they want to provide so they continue to do it. Lethbridge County has a full program in place where they do gravel stabilization using pellet calcium-chloride to do so and provide it for their ratepayers. It’s not a new practice and it does come with a cost,” added Pittman.
Wickson also highlighted the municipalities they contacted were under similar structures when it came to costs.
“We’ve broached it as a level of service for our ratepayers. As far as cost, comparatively, a 50-50 cost share plan is relatively common in our municipalities. There are very few that do oil, one of the primary ones who use oil is Foothills but they are doing mile long sections for country residential areas that are banned from high-level traffic whereas we allow all traffic to go,” he explained.
The number of areas that see calcium applications has also risen significantly since the start of the program.
This year, staff say they have 160 areas for applications.
“It started with 10 applications and now our numbers are substantially higher. The program has grown exponentially over the last few years,” said Pittman.
With the rising growth of the program and constant price increases for products, council wondered about the financials moving forward.
One suggestion was to raise the price of the service to stay in line with inflation.
“If your prices are going up all the time, you could bump it up a little bit,” said Coun. Murray Reynolds, which most of council seemed in favour of.
Currently, they order 30,000 litres of product which staff says is the perfect amount for what they need throughout the year.
Council also questioned if they could make a joint order with a neighbouring municipality to see further cost reduction.
During the course of calcium-chloride based product applications on various roads in the M.D. council also was concerned about the effect it could potentially have on plant life.
While the old product was fairly acidic, staff say the new MG-30 product used is substantially safer.
“We’re closer to 7pH (with MG-30) so it’s not as harmful, it’s more of a neutral product,” explained Wickson.
For the application of the product, the M.D. enlists a contractor with a suitable truck to do the work, as the M.D. doesn’t own the necessary equipment, nor do they feel they need to purchase the needed machinery as it would only be used for a small amount per year.
“The company that does it is a sub-contractor, the one that has done it for the last few years is called Kansas Ridge Trucking. They basically do this whole area, as soon as they’re done here they move over to Warner or Newell. For their cost point, they are using it for six months out of the year. For us, our cost point would not be as good to acquire a spray truck,” said Wickson.
A motion was made to direct staff to complete a complete price breakdown on the Dust Mitigation Program for the next budget meeting and for them to reach out to neighbouring municipalities to investigate a joint purchase of product.
The motion passed unanimously.