Should Downspouts Be Buried or Extended Above Ground?

Both approaches work, and the right choice depends on your lot rather than on which is better in the abstract. Above-ground extensions are easier to inspect, clear, and correct, which makes them the more reliable option for most homes. Buried lines are worth the added complexity when there is genuinely nowhere to send surface water — a narrow side yard, a lot that slopes toward the house, or a discharge point that would create problems for a walkway or a neighbour.

The decision matters because these two options fail in completely different ways. A surface extension fails visibly. A buried line fails silently, often for years, while water quietly returns to your foundation.

Above-ground extensions

Where they work well: lots with usable space and ground that already falls away from the house.

Advantages:

• You can see whether they are working, simply by watching during rain
• Blockages are visible and easy to clear
• Adjusting length or direction is simple
• Freezing is obvious rather than hidden
• No excavation, so no disruption to landscaping or hardscape

Drawbacks:

• Visible, which some homeowners dislike
• Obstruct mowing, and often get removed and forgotten
• Vulnerable to being knocked out of alignment
• Can ice up at ground level during Toronto winters

Buried lines

Where they work well: tight side yards, flat or adverse grading, and situations where surface water would discharge somewhere unsuitable.

Advantages:

• Nothing visible at ground level
• No obstruction to mowing or foot traffic
• Can carry water a considerable distance to a better outlet
• Not vulnerable to being removed or displaced

Drawbacks:

• Failures are invisible until water appears at the foundation
• Roots, sediment, and settling all cause blockages over time
• Clearing requires access points that are often absent
• Freezing is a real risk if the line runs shallow
• Requires excavation to install or repair

The Toronto clay pipe problem

Many older Toronto homes already have buried downspout lines, installed when downspouts were routinely connected directly to the sewer system. That was standard practice before the 1960s, and much of that underground pipe was clay.

Clay pipe does not age well. Joints shift, sections crack, and tree roots find their way in. A line installed sixty years ago is frequently compromised somewhere along its length — and because it is buried, nothing announces the failure.

Toronto has since made downspout disconnection mandatory across the city, phased in with a final deadline of December 3, 2016, with exemptions available where disconnection is not technically feasible. Homes that were disconnected sometimes had the downspout cut at the top of the old buried line without any replacement route being established for the water.

If your home predates the 1960s and has downspouts entering the ground, it is worth establishing where that pipe goes and whether it still functions.

How to decide

Work through these questions in order:

Does the ground already slope away from the house? If yes, a surface extension is likely all you need. Start there.

Is there room for water to travel at least 1.8 metres and keep moving? Narrow side yards between neighbouring houses often fail this test, which is where buried lines earn their keep.

Is there a viable outlet for a buried line? A buried pipe has to daylight somewhere useful — a lower part of the yard, a dry well, or an appropriate connection. Burying a line that has nowhere to discharge just moves the problem underground.

Will the line stay above the frost concern? Shallow buried lines in Toronto can freeze, and a frozen buried line backs water up to the foundation.

Can it be cleaned? Any buried line should include access for clearing. Without it, the first blockage becomes an excavation.

A middle option

Some homes are best served by a hybrid: a surface extension carrying water clear of the foundation, feeding a shallow buried run only where it crosses a walkway or high-traffic area. This keeps most of the system inspectable while solving the specific obstruction.

Where surface options are genuinely constrained, a properly designed French drain can manage both roof water and surface water together. Our post on French gutters covers a related approach.

Frequently asked questions

How do I know if my existing buried line still works?

Watch it during heavy rain. Water backing up at the downspout base, gurgling, or a line that handles light rain but overflows in a downpour all point to a restriction.

Can a buried line be cleared, or does it need replacing?

It depends on the cause. Sediment can often be flushed. Root intrusion and collapsed clay sections usually mean replacement or rerouting.

Do buried lines freeze in Toronto?

They can, particularly shallow runs and the outlet end. A frozen outlet backs the whole line up, which is why depth and discharge design matter.

Is one option more durable?

A well-installed buried line in good soil can last decades. But surface extensions are far easier to keep working, because you can see them. Durability and reliability are not the same thing here.

Choose for maintainability

If your lot allows a surface extension to do the job, that is usually the better decision — not because buried lines are inferior, but because a drainage system you can inspect is a drainage system you will actually maintain.

Where burying is the right answer, it deserves proper design: adequate slope, a real outlet, frost consideration, and access for cleaning. We can assess which approach suits your property. See our downspout and eavestrough services or get in touch.