A snow fence seems backward the first time you see one properly installed.
The driveway is over there.
The snow fence is sitting way out in the field.
Wouldnāt it work better beside the driveway?
Usually, no.
In fact, putting a snow fence too close to the area you are trying to protect can make the drifting problem worse.
That is because a snow fence does not really block snow.
It controls where blowing snow gets dropped.
Once you understand that, snow fences make much more sense ā and they can be remarkably effective on rural properties where the same section of driveway fills in after every winter windstorm.
A Snow Fence Does Not Stop Snow
Snow fences work by changing wind speed.
When wind carrying blowing snow encounters a porous barrier, airflow is disrupted and slowed.
The slower air can no longer carry as much snow.
The snow drops out and forms a drift near the fence instead of continuing all the way to the driveway, road or building you are trying to protect.
The Government of Canada specifically recommends snow fences in rural areas as a way to reduce drifting on roads and paths during winter storms.
The important word is reduce.
You are not eliminating the snow.
You are deliberately encouraging it to accumulate somewhere else.
Think of a Snow Fence as a Drift-Making Machine
This is probably the easiest way to understand one.
You install a fence where you want the snowdrift to form.
That location should normally be far enough upwind that the drift created by the fence does not reach the driveway.
Put the fence right beside the lane and you may simply create an excellent snowdrift exactly where you donāt want one.
The goal is:
Catch the snow before it gets there.
Prevailing Wind Comes First
Before buying a roll of snow fence, determine where the troublesome snow is coming from.
Not where the storm comes from.
Not necessarily where north is.
You need to know the direction of the prevailing winter wind that creates the drifting problem.
On an open rural property, you can often determine this simply by watching the snow.
Look at:
- Drifts along fences
- Drifts around barns
- Snow behind tree lines
- Bare windswept sections of fields
- Repeated drift locations across the driveway
If your driveway fills in from snow carried by west winds, your snow fence belongs on the west ā or upwind ā side of the driveway.
Install the Fence Across the Wind
A snow fence generally works best when it presents a broad barrier across the prevailing wind.
In practical terms, that means the fence typically runs roughly perpendicular to the wind direction.
If the wind blows straight through the fence line from west to east, the fence should generally run north-south.
A fence running parallel to the wind doesnāt provide much barrier.
This sounds obvious, but it is one of the easiest installation mistakes to make when someone simply follows the property line.
The property line and the winter wind may have nothing to do with each other.
Why Is Snow Fence Full of Holes?
Because a solid wall does not behave the same way.
Proper snow fencing is porous.
Some wind passes through it.
That controlled airflow helps create a broad, predictable drift rather than severe turbulence immediately around a solid barrier.
Alberta Transportationās current highway snow-fence specification uses plastic fencing with about 50% porosity.
That means roughly half of the projected fence area is open.
The specification also requires the fence to stand above the ground rather than being buried directly into the surface.
This is not an accident.
The openings are part of how the fence works.
About 50% Porosity Is a Useful Target
Traditional wooden snow fencing achieves porosity through the spaces between slats.
Modern plastic fencing does the same thing with openings in the mesh.
Albertaās highway specifications call for about 50% porosity, and earlier Canadian agricultural research has also treated roughly 50% open area as highly effective for trapping blowing snow.
A solid plywood wall is therefore not automatically a better snow fence.
More solid does not mean more effective.
Snow Fence Should Usually Be Raised Off the Ground
Another feature that can look strange is the gap beneath the fence.
Snow fence should not necessarily touch the soil.
Albertaās transportation specification calls for a bottom clearance of roughly 150 to 300 millimetres, or about 6 to 12 inches.
That gap allows air to move beneath the fence and helps the system develop the intended drift pattern.
It can also reduce how quickly the fence becomes buried.
If a fence disappears completely into the first major drift, much of its useful height is lost.
Distance Is What Makes the System Work
This is the part that matters most for homeowners.
The snow fence needs enough space between itself and the protected area for the drift to form.
Albertaās highway-maintenance guidance notes that a snowdrift created by a fence can extend roughly 10 times the height of the fence.
For highway applications, Alberta historically placed snow fencing approximately 25 to 40 metres from the roadway centreline, depending on local conditions and experience.
That does not mean every four-foot fence beside a private driveway belongs exactly 25 metres away.
Terrain, wind direction, snow supply, fence height and the width of the area being protected all matter.
But it illustrates an important principle:
Snow fences belong well away from the road or driveway, not directly beside it.
A Four-Foot Fence Can Create a Big Drift
Many temporary snow fences are about four feet ā roughly 1.2 metres ā high.
A drift influenced by a fence that size can extend many metres.
That is why a homeowner installing fencing just three or four metres from a driveway may be disappointed.
The fence works.
Unfortunately, it works by putting the drift on the driveway.
Give the snow somewhere else to accumulate.
Donāt Guess Based Only on Summer Conditions
Snow changes the effective shape of the property.
A shallow depression becomes a snow-storage area.
A crop field may be almost flat in summer but generate enormous blowing-snow loads after harvest.
A hedgerow changes wind flow.
A barn can create turbulence.
One of the best ways to design snow control is to observe the first winter.
Take pictures after major wind events.
Mark:
- Where drifting begins
- Where the deepest drift forms
- Which direction the snow arrived from
- Which parts of the driveway remain bare
That information is more valuable than simply looking at the property in July.
Snow Doesnāt Need to Be Falling
Another common misconception is that drifting occurs only during the storm.
Snow can stop falling while strong wind continues moving loose snow across open fields.
That is why a clear blue winter day can still bury a driveway.
The real ingredients are:
- Loose snow
- Sufficient wind
- Open fetch
āFetchā is the open distance over which wind can pick up snow before reaching your driveway.
A lane beside hundreds of metres of open field can receive a tremendous amount of drifting snow.
Open Farm Fields Can Be Perfect Drift Generators
Harvested fields often provide very little wind protection.
Wind travels across the field, picking up loose snow along the way.
By the time it reaches the driveway, it may be carrying a large quantity.
This explains why one country road can repeatedly drift shut while another road a kilometre away stays mostly clear.
The surrounding landscape matters.
Buildings Can Create Their Own Snowdrifts
A barn, garage or house can also affect drifting.
As air moves around the building, wind speeds and direction change.
Snow may accumulate:
- Behind the building
- Around corners
- Between structures
- Along sheltered walls
- Across nearby lanes
Sometimes a driveway problem is caused less by the open field and more by the way buildings channel the wind.
Observe before installing fencing.
Existing Fences Can Make Drifting Worse
Not every fence reduces snow problems.
A solid or poorly located fence can cause snow to accumulate in an undesirable location.
Ontarioās Snow Roads and Fences Act even gives municipalities authority in certain circumstances to require landowners along public highways to alter or remove fences that cause snow accumulation that obstructs travel.
That tells you something important:
A fence can create a drift just as easily as it can solve one.
Location matters.
Temporary Plastic Snow Fence
The familiar orange, green or black plastic mesh fence is popular because it is:
- Lightweight
- Relatively inexpensive
- Easy to store
- Easy to reposition
- Reusable
This makes it useful for figuring out a propertyās snow behaviour.
You can experiment with placement over several winters without committing to permanent landscaping.
If the first location isnāt ideal, move it next year.
Traditional Wooden Snow Fence
Wood-slat snow fence works on the same basic principle.
It has alternating slats and openings that provide controlled porosity.
It is heavier and bulkier than plastic mesh but can be durable and effective.
Some people also prefer the traditional appearance on rural properties.
The physics is more important than the material.
A properly positioned porous fence is what matters.
Fence Strength Matters
Snow fence experiences substantial wind load.
A roll loosely attached to a few flimsy posts may look fine in October and collapse during the first strong December wind.
Posts should be:
- Securely installed
- Properly spaced
- Braced where necessary
Albertaās highway specification calls for approximately one post every 3 metres of fence, with end posts braced.
A private installation doesnāt necessarily have to duplicate highway specifications exactly, but it demonstrates the amount of support these fences may require.
A snow fence lying flat on the ground catches very little blowing snow.
Make the Fence Longer Than the Problem Area
Wind can simply move around the ends of a short fence.
If a 30-metre section of driveway repeatedly drifts in, installing only ten metres of fencing may not solve the problem.
Extend the snow fence beyond the vulnerable section.
The exact distance depends on wind and terrain, but the principle is simple.
You are creating a protected zone downwind.
If the fence ends too soon, blowing snow can curl around it.
Watch for Gaps
Large openings in the middle of a snow fence can concentrate airflow.
A gate or missing section may create a channel through which blowing snow travels.
That does not mean the fence must be completely continuous across the entire farm.
It means openings should be planned rather than accidental.
Donāt Block Your Own Drainage
Where the drift forms matters after winter too.
Snow stored by a fence eventually melts.
If the fence deposits a huge drift directly into:
- Roadside ditch
- Culvert entrance
- Septic area
- Building foundation
- Low yard
- Barn entrance
you may solve the winter drifting problem and create a spring-water problem.
Think through the entire seasonal cycle.
Where will all that snow go when it melts?
Keep Snow Away From Culverts
This matters especially on long rural driveways.
If a snow fence causes a large drift to accumulate over a culvert or drainage channel, spring melt can overwhelm or block the system.
Your snow-management plan should complement your drainage plan.
Winter and spring are connected.
Snowbanks Can Become Accidental Snow Fences
Snowplowing itself changes the way wind moves across a driveway.
A high snowbank beside the lane can act like a solid barrier.
Then the wind drops more snow immediately behind it.
The next storm adds another layer.
The driveway becomes narrower and increasingly difficult to keep clear.
Where possible, push snow far enough away early in the season to leave storage room for later storms.
Donāt Build a Wall Beside the Lane
This is especially important with long rural driveways.
If you continuously plow snow into a tall wall immediately beside the travel surface, that bank can encourage drifting back onto the driveway.
By February, you may feel as though the driveway fills in five minutes after you plow it.
Sometimes moving existing banks farther away can improve conditions almost as much as installing a fence.
Living Snow Fences
A snow fence does not have to be made from plastic or wood.
Rows of trees and shrubs can function as a living snow fence.
Ontario has promoted snow hedges along highways as a strategy for reducing severe drifting while also providing environmental benefits.
Living barriers can provide:
- Snow control
- Wind reduction
- Wildlife habitat
- Visual screening
- Carbon storage
- Soil protection
They take much longer to establish but can become a permanent solution.
A Windbreak Is Not Automatically a Good Snow Fence
Tree placement matters just as much as temporary fence placement.
Plant trees immediately beside the driveway and they may cause snow to drop onto the driveway.
A well-designed living snow fence needs adequate setback so the snow accumulates before reaching the travel surface.
This is why windbreak planning deserves some thought.
In #17 of this series, Planting a Rural Windbreak, weāll look at tree selection, spacing and other benefits in much more detail.
Corn Rows Can Trap Snow Too
Farmers sometimes leave standing crop rows or tall stubble in strategic locations to catch snow.
The same aerodynamic principle applies.
Anything that slows wind can encourage snow deposition.
Temporary vegetative barriers can sometimes reduce drifting while also keeping manufactured fencing out of the field.
The details depend on the farming operation and field layout.
Straw Bales Are Sometimes Used
Rows of large straw bales can act as temporary wind barriers and trap snow.
They are not always ideal.
They are:
- Heavy
- Bulky
- Attractive to rodents
- Temporary
- Potential obstacles for field operations
But in some situations they can provide an inexpensive way to experiment with drift control.
Again, placement matters more than simply putting something in the wind.
Watch Visibility Near the Road
Do not install snow fencing where it blocks visibility for vehicles entering a public road.
A rural driveway entrance needs clear sightlines.
Likewise, do not place a permanent windbreak so close to an intersection or entrance that it creates a visibility problem.
Snow-control improvements should not create traffic hazards.
Check Before Installing on Land You Donāt Own
This sounds obvious, but rural properties can have complicated boundaries.
The ideal location for a snow fence might technically be:
- On neighbouring land
- Within a municipal road allowance
- Inside an easement
- Along rented farmland
Get permission before installing anything.
Our #9 article, Where Does My Property Actually End?, explains why the edge of a field or fence line should not automatically be treated as the legal property boundary.
Municipal Snow Fences Are Different
Ontario municipalities have statutory authority to erect snow fencing on land along highways under certain circumstances.
The Municipal Act, 2001 allows a municipality to enter land along a highway under its jurisdiction for the purpose of erecting and maintaining a snow fence.
Ontarioās Snow Roads and Fences Act also contains provisions for seasonal municipal snow fencing and snow-related fence issues.
Those provisions relate to public-road management.
A private homeowner installing a fence to protect a private lane is dealing with a different situation, but it is useful background for understanding why snow fences appear far out in agricultural fields beside Ontario roads.
Why Is the Municipal Fence So Far From the Road?
Now you know.
The municipality isnāt wasting fencing.
It wants the drift to form out in the field instead of on the road.
The big setback provides snow-storage space.
That is exactly the same principle you can use for a country driveway.
Snow Fences Work Best Before the Drift Problem Starts
Installing a fence after two metres of snow has already accumulated is not particularly helpful.
Temporary fencing should go up before the winter drifting season.
Alberta highway guidance calls for installation after farming operations are finished but before winter.
Ontario law has historically allowed municipal snow fencing to be placed seasonally beginning in mid-November.
For a homeowner, the exact date is less important than this:
Install it while the ground is workable and before you need it.
Remove Temporary Fencing in Spring
Plastic and wooden temporary fencing does not necessarily need to remain in the field all year.
Spring removal:
- Keeps it out of farming operations
- Reduces UV exposure
- Prevents damage
- Makes mowing easier
- Keeps the property tidier
Inspect the fencing while removing it and repair damaged sections before storage.
Then next fall, you are ready.
The First Installation May Not Be Perfect
Snow fencing involves real-world wind.
Real properties contain:
- Hills
- Trees
- Buildings
- Ditches
- Fields
- Existing fences
A textbook placement may need adjustment.
Treat the first winter as a test.
Take photographs after major storms.
If the drift ends three metres short of the driveway, excellent.
If it reaches the lane, move the fence farther upwind next year.
If snow continues coming around one end, extend the fence.
Rural property management often involves observing, adjusting and improving.
A Simple Snow-Fence Planning Method
Step 1: Find the Problem
Identify exactly which sections of driveway repeatedly drift shut.
Step 2: Determine the Wind Direction
Identify the prevailing wind responsible for those drifts.
Step 3: Find the Upwind Side
That is where the fence belongs.
Step 4: Give the Drift Room
Place the fence well away from the driveway so the accumulated snow has enough space.
Step 5: Use Porous Fencing
Around 50% porosity is common in engineered snow-fence applications.
Step 6: Raise It Slightly
Maintain an appropriate bottom gap instead of burying the fence against the ground.
Step 7: Extend Beyond the Problem
Donāt allow wind to simply wrap around the ends.
Step 8: Observe
See where the drift actually forms.
Step 9: Adjust Next Year
Treat placement as something that can be refined.
Common Snow-Fence Mistakes
Putting It Beside the Driveway
Probably the biggest mistake.
You may create the drift directly on the road.
Using a Solid Barrier
Snow fencing works through controlled porosity.
Installing It Downwind
The fence needs to intercept the snow before it reaches the protected area.
Installing Too Short a Fence
Wind and snow can move around the ends.
Forgetting About Spring Melt
The stored snow eventually becomes water.
Ignoring Buildings and Terrain
Real wind rarely behaves exactly like arrows on a diagram.
Waiting Until the Ground Is Frozen
Installing posts is much easier before winter.
Sometimes a Snow Fence Is Better Than a Bigger Snowblower
There is a natural tendency to solve drifting with more snow-removal equipment.
A bigger snowblower.
A heavier plow.
A larger tractor.
Sometimes that is necessary.
But if the same 20 metres of driveway fills in after every northwest wind, continually removing the snow may not be the smartest solution.
Stopping the drifting before it reaches the driveway can reduce:
- Fuel use
- Equipment wear
- Snow-removal time
- Large snowbanks
- Repeated plowing
The cheapest snow to remove is the snow that never lands on the driveway.
Watch What the Snow Is Telling You
Snow makes wind visible.
A drift is a record of how air moved across your property.
Pay attention to it.
Where is the snow deepest?
Where is the ground almost bare?
Where does the drift begin?
What is directly upwind?
Once you start looking at a rural property this way, winter stops looking completely random.
The snow is showing you exactly where the wind is slowing down.
Snow Fences Are About Moving the Problem
That is the key concept.
A snow fence does not make blowing snow disappear.
It moves the accumulation to a place where it causes fewer problems.
Done properly:
The field gets the drift.
The driveway stays clearer.
Done poorly:
The driveway gets an even bigger drift.
Placement is everything.
So before spending another winter repeatedly clearing the same section of lane, stand outside during the next windy snowfall and watch where the snow comes from.
The solution may not be another pass with the tractor.
It may be a four-foot fence sitting twenty metres out in the field doing nothing more complicated than convincing the wind to drop its snow early.
Verified Sources
Government of Canada ā Winter Storms: How to Prepare. Current federal emergency guidance specifically recommends installing snow fences in rural areas to reduce drifting snow on roads and paths.
Government of Canada ā Winter Storm Preparedness
Alberta Transportation ā Supply and Install Snow Fence, Specification 52.3. Albertaās highway specification provides useful engineering details applicable to the article: plastic snow fencing is specified at 50% porosity, approximately four feet high, with a bottom clearance of 150ā300 mm, one post roughly every three metres and installation on the prevailing-wind side of the posts.
Alberta Transportation ā Snow Fence Specification 52.3
Alberta Transportation ā Highway Maintenance Guidelines. Albertaās maintenance manual says snow fences should be used where drifting is prevalent to reduce roadway accumulation and improve visibility. It places highway fences roughly 25ā40 metres from the roadway centreline according to local conditions and notes that the drift can extend about 10 times the fence height.
Alberta ā Highway Maintenance Guidelines and Level of Service Manual
Ontario ā Snow Roads and Fences Act. Ontario law provides municipalities with powers relating to snow fences along public highways, including authority to address existing fences that cause snow accumulation obstructing travel and to erect seasonal snow fences on adjacent lands under the Actās provisions.
Ontario ā Snow Roads and Fences Act
Ontario ā Municipal Act, 2001. Section 60 authorizes municipalities to enter land along highways under their jurisdiction for the purpose of erecting and maintaining snow fences. This helps explain why municipal snow fencing can appear well inside farm fields beside Ontario roads.
Ontario ā Municipal Act, 2001
Ontario Transportation Planning ā Snow Hedges. Ontario has identified planting āsnow hedgesā or living snow fences of trees and shrubs along roads experiencing severe drifting as a strategy to improve road safety while providing environmental benefits.
Government of Yukon Agriculture Branch ā Trapping Snow Moisture. Yukon agricultural guidance describes porous snow fencing as a snow-management tool and notes that approximately 50% porosity is effective for trapping blowing snow.
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