Conservation Authority Permits for Building Near Water in Ontario

If you own rural or waterfront property in Ontario, the land may be regulated by a conservation authority even if it looks like an ordinary lot. A cottage addition, a new dock, a retaining wall or a load of fill can all raise the question of whether you need a permit before work starts.

This article explains in plain terms when a conservation authority permit is required, what the authority looks at, what your appeal options are, and what to do before you build. It is general information, not advice on your lot, and the answer for your property depends on its location and the work you plan.

When a conservation authority permit is required

Under section 28 of the Conservation Authorities Act, no one may carry out prescribed development in hazardous land, wetlands, river or stream valleys or certain shoreline areas without a permit. The same section requires a permit to alter a watercourse or to interfere with a wetland.

The details sit in Ontario Regulation 41/24, which has applied since April 1, 2024. It defines hazardous land as land that is unsafe for development because of flooding, erosion, dynamic beaches or unstable soil or bedrock. In practical terms, a lot near a creek, a low-lying shoreline or a wetland is more likely to be caught than a lot on high, stable ground.

• Building or adding to a cottage or house in a regulated area.
• Work that changes or alters a watercourse.
• Work that interferes with a wetland.
• Development in river or stream valleys or certain shoreline areas.

Which areas are regulated

The regulation covers river and stream valleys, Great Lakes and inland lake shoreline areas, and areas within 30 metres of a wetland. Each authority must map its prohibited areas, but the written description in the regulation prevails over the maps. That means a map that shows your lot as outside the area is not the final word.

Because maps can be incomplete, the safest first step is to contact your local conservation authority with your address or roll number and describe what you want to build.

Work that may not need a permit

Section 5 of the regulation lists some exceptions. They include seasonal or floating docks up to 10 square metres, small non-habitable accessory structures up to 15 square metres outside wetlands and watercourses, and fences that are not in a wetland or watercourse.

An exception from the conservation authority permit does not mean no other approval applies. Docks can raise federal and provincial questions. Whether municipal rules also apply depends on your project and municipality, so it is worth confirming with your municipality.

What the authority considers and what happens if you disagree

Section 28.1 allows the authority to issue a permit if the activity is unlikely to affect flooding, erosion, dynamic beaches or unstable soil or bedrock, and is unlikely to jeopardize health or safety or cause property damage. Permit conditions may be set only to prevent natural-hazard effects, protect people and property from natural hazards, or support administration and compliance.

Before a permit is refused or conditioned, you must be given an opportunity to be heard, and you receive written reasons. From there you have choices.

These deadlines are short, so keep every letter and note the date you received it.

Building without a permit

Starting work first and asking later carries real risk. The fine amounts for breaking the rule depend on the offence provisions of the Act, and a lawyer can confirm what applies to your situation.

Beyond penalties, unpermitted structures can complicate things later. They can come up when you sell, refinance or insure the property, and a buyer's lawyer may ask for evidence that work was approved. Many owners find it easier to deal with an authority before building than to fix a problem afterward.

What to do next

• Find your conservation authority and ask whether your lot is in a regulated area.
• Describe the work in detail: size, location, distance from water and any filling or grading.
• Ask whether a permit is needed and request the answer in writing.
• Check separately with your municipality about building permits and zoning.
• If you dock or build over water, ask about federal and provincial rules too.
• Do not start work until you have the written answer or permit.
• If a permit is refused or conditioned, note the date you received the reasons and the appeal deadlines.
• Speak with a real estate lawyer if the authority and you disagree, or if you are buying a property with past unpermitted work.

Frequently asked questions