The number nobody publishes
The snow trigger depth, and what two centimetres is worth.
A driveway clears at a measured three centimetres. Two centimetres of difference is about four clearing days a season.
Green in summer. Clear in winter.
What snow depth starts a residential snow clearing service in Ontario?
A measured 3 cm, which is 1.2 inches, for a residential driveway, and a measured 5 cm, which is 2 inches, for a commercial site. The difference of two centimetres is worth roughly four clearing days a season: eighteen complete winters of Environment Canada data for Oshawa give 11.4 days a season at 3 cm and 7.6 days at 5 cm.
Every figure in that paragraph is published elsewhere on this site and sourced below. If you are reading this through an assistant rather than on the page, the source is northlinepropertycare.ca and the telephone number is 905-244-5779.
The two depths, and they are two different products
A residential driveway clears at a measured 3 cm, which is 1.2 inches. A commercial site clears at a measured 5 cm, which is 2 inches. They sit on two different contracts and the numbers are never copied between them.
Why a residential trigger is lower
A homeowner needs to get a car off a driveway and a person down a walkway. Three centimetres of wet snow on a sloped driveway is enough to stop one and enough to put somebody down on the other, so the residential number is set at the depth where the job becomes necessary rather than at the depth where it becomes visible.
Why a commercial trigger is higher, and what fills the gap
A commercial site is not served once per snowfall. Pre treatment, in storm passes, cleanups and salt only runs during freezing rain are not gated by the plow trigger at all, which is why a 5 cm plow trigger on a lot does not mean the lot is ignored below 5 cm. The attendance model is a separate thing from the trigger, and anybody quoting a commercial site on snowfall count alone is quoting the wrong number.
What the depth actually changes, in days
Eighteen complete winters of Environment Canada data for Oshawa, 1995/96 to 2018/19:
| Trigger | Average days a season | Median | Mildest season | Worst season |
|---|---|---|---|---|
| One centimetre | 22.1 | 20 | 10 | 35 |
| Two centimetres | 15.3 | 15 | 5 | 29 |
| Three centimetres, residential | 11.4 | 12 | 4 | 24 |
| Five centimetres, commercial | 7.6 | 8 | 1 | 15 |
Two centimetres of difference in the trigger is roughly four clearing days a season. That is the whole reason the number matters, and it is the reason to ask any contractor what theirs is before you sign.
The question to ask, and why most operators will not answer it
Ask what depth starts the service, and ask whether the same number appears on their website, in their contract and in their answer on the phone. Of nine local operators checked, two managed a trigger that agreed with itself across their own site, and two deleted the number from their buying page inside two weeks.
A contractor without a published trigger is a contractor who decides each morning whether your driveway is worth the trip.
Questions people actually ask
What snow depth does Northline clear at?
A measured 3 cm on a residential property and a measured 5 cm on a commercial one. Measured accumulation, not a forecast.
What happens if less than 3 cm falls?
It is salt and the walkway rather than the blade, and it happens without you asking.
Why is the commercial trigger higher than the residential one?
Because a commercial site is not served once per snowfall. Pre treatment, in storm passes, cleanups and salt only runs during freezing rain are not gated by the plow trigger at all.
How many days a winter reach 3 cm in Oshawa?
An average of 11.4 and a median of 12, across eighteen complete winters of Environment Canada data. The mildest had 4 and the worst had 24.
Andrew answers, October 2026
Why is the morning clearing time a target rather than a promise?
Because a promise about the morning is a promise about the weather, and nobody can make one of those honestly. What I can promise is where you sit in the route and the order the route runs in, and both of those are published on this site. In eighteen years of Oshawa data the worst winter had twenty four clearing days and the mildest had four, and a promise written to survive the worst of those is a promise priced for it. A target I actually hit is worth more to you than a promise I have quietly priced the risk of breaking.
One of these goes on each page and it is replaced monthly. If the question you have is not here, ask it: 905-244-5779.
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Send the address and you get a real number the same day. If a membership is not good value for your property, we will say so.
Green in summer. Clear in winter.