Drainage Conflict - Natural Watercourses

When responding to issues involving a natural watercourse, the courts often take the position that "water flows naturally and should be permitted thus to flow". If you own land on one or both sides of a natural watercourse, you are considered to be a riparian landowner. A non-riparian land owner does not have land abutting a natural watercourse. The following questions are addressed in this section:

What is a natural watercourse?

A natural watercourse is a natural channel where water flows between banks that are more or less defined. The flow of water does not need to be constant, but the channel must be a permanent landmark. The watercourse may also, at some point, spread over a level area without defined banks, before flowing again as a defined channel.

A natural watercourse

How do I know whether the area on my land would be considered a natural watercourse?

Only a judge can conclusively determine whether, under the law, a specific flow of water is a natural watercourse or not. Many people have opinions, and here are some guides or suggestions for evaluating the watercourse on your land:

  1. The channel must be a permanent, natural feature on the land. A man-made ditch is not a natural watercourse. The courts may or may not consider a natural watercourse that has been modified in the past to still be considered a natural watercourse;
  2. Water flows through a channel that has a bed and banks. If the water spreads out from the banks at some point, it must eventually flow back into a defined channel with banks and a bed;
  3. The water flow in a natural watercourse does not have to be continuous, but must be significant. If water only flows after a heavy rain, it may not be a natural watercourse even if it has defined banks.

What are the rights and responsibilities of a riparian landowner?

The following is a general summary of the rights and responsibilities of riparian landowners.

The law concerning riparian rights and responsibilities is complex, and cannot be easily summarized. Please consult your lawyer where these rights and responsibilities affect your property or a neighbouring property.

Right of drainage

Riparian landowners have the right to drain their land into the natural watercourse, even if it causes damage to downstream property owners. Non-riparian property owners do not have the right to drain into natural watercourses, and the connecting non-riparian landowner could be liable for damages if downstream damages result.

Right to use water for domestic purposes

Riparian landowners have the right to use the water in a natural watercourse for domestic purposes, provided they only use a reasonable amount. They must not take all the water in the watercourse, depriving downstream riparian property owners of their right to use the water for their purposes. The Permit to Take Water process under the Ontario Water Resources Act may override this common law principle.

Can't interfere with the channel to the detriment of others

Riparian landowners can modify the channel of a natural watercourse provided it doesn't interfere with the general principle that "water flows naturally and should be permitted thus to flow". Any interference with this principle may be grounds for a lawsuit. However, there may also be legislation that regulates work in the channel of a natural watercourse. The local conservation authority and the Ministry of Natural Resources' offices are good starting places to find out what laws may apply.

Can't dam a natural watercourse

Blocking a natural watercourse is in direct conflict with the general principle for natural watercourses that "water flows naturally and should be permitted thus to flow".

Must accept the water

If water overflows a natural watercourse and floods your property, you must accept the results. If damage is caused by the actions of upstream non-riparian landowners, you don't have to accept the water and may have grounds for legal action. Rejecting water could involve an impervious wall, berm or dyke along the boundary of your land, and effectively dam the water back on the higher lands of the non-riparian owner.

What are some common problems or disputes involving natural watercourses?

  1. Natural blockage
  2. Artificial blockage
  3. Increased flow

Natural Blockage

Naturally-occurring blockages in natural watercourses occur for a variety of reasons, including beaver dams, fallen timber, debris or sediment buildup. These blockages hold back water, flooding the adjoining land and even upstream land.

My land is being flooded because of a natural blockage on my property. What am I allowed to do?

You may be able to remove the blockage yourself, but consider the following cautions.

  • Check the environmental regulations that may apply – permits or authorizations may be required.
  • If the blockage has been there for some time, your riparian neighbours may have come to rely on that blockage in the watercourse. If removing the blockage changes the amount or speed of water in the watercourse – and that causes damage to another riparian owner's property – that owner could take legal action against you for the property damage. Make certain these neighbours are consulted and involved in the process.

You have the right to petition your municipality to legally change the watercourse into a municipal drain.

  • The Drainage Act process must be followed and the municipality has to comply with environmental regulations – changing a natural watercourse to a municipal drain may take some time.
  • Once the natural watercourse becomes a municipal drain, the Drainage Act governs the management of the watercourse. The municipality has the responsibility to keep the drain maintained and free from blockages.

There is a natural blockage along my edge of the watercourse that I want to remove. What can I do?

There are a few options open to you.

  • Remove the blockage yourself. Contact the Ministry of Natural Resources first to obtain proper permits for removing the obstruction from a watercourse. There may be a fee for these permits.
  • Get the municipality to turn the watercourse into a municipal drain by petitioning under Section 4 of the Drainage Act. Once the watercourse is a municipal drain, the municipality has the duty to keep it clear from obstructions.

My land is being flooded because of a beaver dam or other natural blockage on my neighbour's property. Isn't it the municipality's job to remove it? What about the conservation authority or the Ministry of Natural Resources?

If the watercourse was a municipal drain, your municipality has the authority and responsibility to maintain the drain. But municipalities have no authority to remove blockages from a natural watercourse.

The conservation authority or Ministry of Natural Resources also has no authority to go onto private land to remove naturally-occurring blockages.

My upstream neighbor has advised me that there is flooding on their land because of blockages on the natural watercourse located on my land. They want to do some work on the natural watercourse. I am afraid that the extra water will hurt my land. Do I have to let them do the work?

If this is a natural blockage on a natural watercourse, you do not have to give your neighbour permission to perform the work. Talk to your neighbour to negotiate a solution. They may need to contact the Ministry of Natural Resources to find out whether a permit is necessary to remove the artificial blockage.

Please remember, if your neighbour is frustrated that they cannot resolve their flooding problem, they have the right to petition the municipality for a municipal drain.

What options are available to me?

If the blockage occurs on your neighbour's property, talk to them about getting permission to remove the blockage. Remember your neighbour does not necessarily have a responsibility to remove the blockage on your behalf. If your neighbour grants permission, you have to comply with all environmental regulations.

If negotiation fails, you have the right to petition your municipality under the Drainage Act to turn the watercourse into a municipal drain. The Drainage Act process must be followed and the municipality has to comply with environmental regulations. Changing a natural watercourse to a municipal drain may take some time.


Artificial blockage

A variety of actions could be considered an artificial blockage or dam on a natural watercourse, including small dams, undersized culverts or fences that run through a natural watercourse and collect branches and other debris which hold back water.

My land is being flooded by an artificial blockage on a natural watercourse on my neighbour's property. What can I do?

Talk to your neighbour to negotiate a solution. Your neighbour may need to contact the Ministry of Natural Resources to determine if a permit is necessary to remove the artificial blockage.

Contact the Ministry of Natural Resources to see if your neighbour has built the artificial blockage in compliance with environmental regulations.

  • As a riparian neighbour, you should have been consulted during your neighbour's process of obtaining a permit. If you were not consulted before they built the artificial blockage, your neighbour may not have gone through the proper legal channels;
  • If your neighbour did not obtain the proper permits, the Ministry of Natural Resources may be able to enforce environmental regulations to resolve your problem;

Consult your lawyer and see what legal options are available to you. This may include initiating a legal action.

Petition your municipality to turn the watercourse into a municipal drain under the Drainage Act.

  • If a blockage causes drainage problems, you can petition your local municipality to turn the watercourse into a drain, as set out by Section 4 of the Drainage Act;
  • If the municipality determines a municipal drain is required, they have the right and duty to keep the drain maintained and free from blockages;
  • The project has to comply with environmental regulations, and may take some time to reach completion.

I want to build a dam on a natural watercourse on my property. What do I have to do?

You may not alter a watercourse by building an artificial blockage. If you do, any affected owner along the watercourse can sue you for damages, or ask a judge for an injunction to force you to remove the dam.

Building a dam on a natural watercourse can interfere with the riparian rights of property owners both upstream and downstream.

I am being deprived of water because of upstream blockage. What can I do?

If the blockage is artificial, and the neighbour who built it refuses to remove it, you can apply to the courts for damages or an injunction. An injunction forces the person responsible for the blockage to remove it.

Contact the Ministry of Natural Resources for assistance. If a person wants to build a blockage in a watercourse, they must get Ministry of National Resources' permits. During the permitting process, before your neighbour built the blockage, you and other landowners should have been consulted. If you were not, your neighbour may not have obtained proper permits.


Increased flow

My upstream neighbour removed a beaver dam and now my field is being flooded. What can I do?

A person removing a beaver dam must comply with environmental regulations. Check with environmental agencies to see if this approval was received.

Consult your lawyer to see what legal options are available to you. This may include initiating a legal action.

The flow of the creek going through my property has increased due to land use change (e.g. new subdivision or quarry operation) in the upper part of the watershed and now my land floods. What do I do?

Petition your municipality to turn the watercourse into a municipal drain under the Drainage Act. The project will have to comply with environmental regulations.

Only riparian landowners have the right to drain into a natural watercourse. You could initiate legal action if your flooding is caused by non-riparian lands draining into the natural watercourse.


For more information:
Toll Free: 1-877-424-1300
E-mail: ag.info.omafra@ontario.ca
Author: OMAFRA Staff
Creation Date: 28 April 2011
Last Reviewed: 28 April 2011