Neighbour's Water Draining Onto My Property in Ontario

You notice a pool of water along the fence line, a soggy lawn, or water in the basement. The cause seems to be next door: a downspout pointed your way, a sump pump hose, new tile drainage, or a yard that was regraded. It is stressful, and it is hard to know where to start.

This article explains the general Ontario rules on water that moves from one property to another, the exceptions that can change the answer, and the practical routes to a fix. Your facts matter a great deal, so a lawyer can confirm how the rules apply to you.

The basic rule: surface water has no right of drainage

Under Ontario common law, surface water has no right of drainage. Collected or discharged surface water, such as tile drainage, roof runoff or road ditch water, must not be diverted onto land that would not naturally receive it, or liability for damages can follow.

In plain words, a neighbour is generally not allowed to gather water into a pipe, pump or channel and send it onto your land. That is different from water that simply flows across the land in its natural way. Whether a particular downspout, pump or slope crosses the line depends on how the water moved before and after the change.

• Downspouts or roof runoff aimed at your yard
• Sump pump discharge that ends up on your side
• Tile drainage that outlets onto your land
• Regrading that sends water where it did not go before

When a neighbour may have a right to drain

There is an exception. A right to drain collected water onto a neighbour's land may arise from 20 years of continuous, open, peaceful, uncontested use without permission. A court must confirm the right, and it can be lost if the drainage is increased.

So long-standing drainage is not automatically unlawful, but a new or enlarged flow is a different story. Signs of an increase might include a new roof addition, more paving or a new pump. Keep photos and dates that show how things looked before.

Neighbours can also agree in writing. Two or more owners can make a written agreement under s. 2 of the Drainage Act. If it is registered on title, it binds future owners, and it is maintained according to its terms. Enforcement is only through court action.

Grading, fill and municipal rules

A local municipality may prohibit or regulate the placing or dumping of fill, the removal of topsoil and changes to the grade of land. It may also require permits and impose permit conditions. If a neighbour raised their yard or added fill without a required permit, the municipality may be able to act.

These by-laws have exemptions. They do not apply to activities by a municipality, to drain construction under the Drainage Act or to certain pit and quarry operations. Topsoil removal that is incidental to normal agricultural practice is also exempt, but not removal for sale or other disposition.

Grading by-laws and permits vary by municipality, and Toronto acts under the City of Toronto Act, 2006. Check your own municipality's by-law and ask its by-law or building staff how to make a complaint.

Legal remedies and time limits

Private nuisance is an act that indirectly causes physical injury to land, or substantially interferes with its use or enjoyment, where the injury or interference is unreasonable in light of all the surrounding circumstances. Nuisance looks at the effect on your property rights, not at whether the neighbour was careless.

• Injunction: a Superior Court of Justice judge may grant an interlocutory injunction or mandatory order where it appears just or convenient to do so.
• Damages: a court that can grant an injunction may award damages in addition to, or instead of, the injunction.
• Small Claims Court: it hears money claims up to $50,000, not counting interest and costs.

The basic limitation period is two years from the day the claim was discovered. A claim is discovered on the earlier of the day you actually knew the relevant matters and the day a reasonable person in your position ought to have known them. No proceeding may be started after the 15th anniversary of the act or omission, whatever the date of discovery.

What to do next

• Photograph and video the water, the source and the damage, with dates, especially during rain or thaw.
• Note when you first saw the problem, since time limits can run from discovery.
• Check your home insurance policy and report damage promptly, as coverage depends on the wording.
• Look up your municipality's grading and site alteration by-law and ask about complaints.
• Write to your neighbour calmly, describing the problem and asking for a fix, and keep a copy.
• Get advice before starting a claim or doing work on the shared boundary.

A lawyer can look at how long the drainage has existed, what changed, and which route fits your situation.

Frequently asked questions