Neighbour's Grading or Downspout Floods Your Yard: Ontario Rights

You notice water pooling along your foundation, or a wet patch that never used to be there. Then you see that your neighbour has regraded their yard, brought in fill, or pointed a downspout or drain toward your side. It is natural to wonder what the rules are and what you can actually do.

This article explains the main rules that apply in Ontario: the common-law rule on surface water, municipal by-laws on changing the grade of land, civil claims such as nuisance, and the time limits. Details vary by municipality and by the facts, so treat this as a starting point and not a substitute for advice on your own situation.

The basic rule on surface water

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, your neighbour generally cannot gather water into a pipe, spout or channel and send it onto your property if it would not have flowed there naturally. The rule is about water that has been collected or redirected, so the details of how the water got to you matter.

When a neighbour may have a right to drain onto your land

There is a narrow 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.

• The use must have been continuous, open and uncontested for the full period.
• It must have happened without your permission.
• A court has to confirm it; it does not simply arise on its own.
• If the neighbour has increased the drainage, the right can be lost.

If the grading or downspout change is recent, this exception is unlikely to help your neighbour. If the drainage has been there for decades, get advice before assuming you can stop it.

Grading, fill and municipal by-laws

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. So a neighbour who raised their yard with fill or reshaped the grade may have needed a permit.

Some activities are outside these by-laws. 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.

Permit rules, thresholds, fines and complaint channels differ from one municipality to the next. Toronto acts under the City of Toronto Act, 2006, not the Municipal Act, 2001, so check your own municipality's by-laws and contact its by-law or building office.

Civil claims: nuisance, injunctions and damages

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 your neighbour was careless.

A Superior Court of Justice judge may grant an interlocutory injunction or mandatory order where it appears just or convenient to do so. A court that can grant an injunction may also award damages in addition to, or in place of, the injunction.

For money claims, the Small Claims Court hears claims up to $50,000, exclusive of interest and costs. Which court is the right one depends on what you are asking for and how much is at stake, so it is worth confirming with a lawyer before you start.

Time limits and practical next steps

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 circumstances ought to have known them. No proceeding may be started after the 15th anniversary of the day the act or omission took place, whatever the date of discovery.

A neighbourly solution may also be possible. Many water problems are first raised in a calm conversation, and if your neighbour agrees to change the drainage, putting the agreement in writing helps both of you. How to make an agreement last when a property is sold depends on your situation, so it is worth confirming with a lawyer.

• Photograph the water, the grading, the downspout and any fill, with dates.
• Note when you first saw the problem, since time limits can run from discovery.
• Keep records of repairs, damage and costs, including insurance communications.
• Ask your municipality whether a permit was required for the work.
• Raise it calmly with your neighbour and put any agreement in writing.
• Speak with a lawyer before the deadline gets close or before you alter the drainage yourself.

Frequently asked questions