Conservation Authority Approvals in Ontario: A Simple Guide

The TL;DR on Conservation Authority approvals

Conservation Authorities (CAs) do not exist to stop your project for sport. Their job is to manage natural hazards – flooding, erosion, unstable slopes, dynamic beaches – and to protect wetlands and watercourses in regulated areas. If your property falls in a regulated area and you are doing certain activities, you may need a permission (often called a “Section 28 permit”) before your municipality can issue a building permit.

First: what a Conservation Authority is (and what it isn’t)

A Conservation Authority is a watershed-based public agency in Ontario. “Watershed-based” is a fancy way of saying they follow the water, not the municipal boundary line. That is why two lots on the same road can have totally different rules – because one lot drains to a creek and the other drains to your neighbour’s sump pump.

Here is the important part: a CA usually is not your building department and it is not your planning department. Your municipality handles zoning, building permits, and inspections. The Conservation Authority handles specific regulated activities in regulated areas related to hazards and certain features like wetlands and watercourses. Two different offices, two different jobs.

What triggers “CA approvals” in Ontario

Most homeowner CA approvals fall under the Conservation Authorities Act “Section 28” framework. The short version: certain activities are prohibited in regulated areas unless you get permission. Ontario now has a province-wide regulation that sets the core rules for prohibited activities, exemptions, and permits. In plain English, the activities that commonly trigger CA involvement are:

• Development in a regulated area – building, additions, structures, sometimes pools and decks, depending on location and definition.
• Interference with a wetland – even “small” changes can be a big deal in wetland world.
• Alteration to a watercourse or shoreline – straightening, diverting, culverts, bank work, shoreline stabilization, and the like.

And the regulated area commonly includes floodplains, erosion hazard areas, river and stream valleys, unstable slopes, certain shorelines (Great Lakes and many inland lakes), wetlands, and the lands around them. In other words: if water can move there, has moved there, or wants to move there, it is probably on someone’s map.

Regulated area maps: why your lot “looks safe” but still needs approval

Homeowners often say, “But the lot is high and dry.” Great. That might still be inside a regulated area, because regulated areas are based on mapped hazards and features – not just today’s weather. Floodplains are about the big events. Erosion hazards are about long-term slope stability. Wetlands do not care if it is a sunny day when you take the listing photos.

Most CAs provide regulated-area mapping tools, and many municipalities will flag CA involvement during permit intake. But here is the problem: buyers often discover this after they close, because real estate listings do not come with a free hydrologist. The classic scenario: you buy a beautiful lot near a creek, call the municipality about a building permit, and they say “you will need Conservation Authority clearance first.” You say “but the creek is way over there.” They say “yes.” You have a tape measure; they have a hazard map. The map wins.

What the CA is actually checking (the real checklist)

When a CA reviews a permission application, they are generally trying to confirm your proposal will not create negative impacts related to hazards and regulated features. Here is the builder-friendly version of what they care about:

If your proposal can demonstrate those things, permissions are often straightforward. If it cannot, the CA may require changes, conditions, or in some cases refuse. That is where projects stall – and where homeowners feel the CA is “being difficult,” even though the file is actually just missing proof.

The approval process in Ontario (what it actually looks like)

Every CA has its own checklists and workflows, but the skeleton is usually similar:

1. Figure out if you’re regulated

   Confirm your property is inside (or near) a regulated area, and what activity you are proposing.

2. Pre-consultation / screening

   Many CAs will do a pre-screen or advise what studies are needed before you formally apply.

3. Prepare drawings + studies

   Site plan, grading, erosion controls, and any required technical reports.

4. Submit application + fee

   Submit the full package. Incomplete packages are the number-one cause of delay.

5. Completeness check

   The CA confirms whether the application is “complete” – this is the detail that controls your timeline.

6. Review, decision, conditions

   The CA issues a permission with conditions, requests revisions, or refuses.

What you may be asked to provide (and why)

Homeowners are often shocked by the list of required documents. But most items have a purpose: they prove your project will not worsen hazards or harm regulated features. Depending on the site and the proposal, a CA may ask for some of these:

• Topographic survey or detailed site plan – existing grades, features, setbacks to hazards, and where the work goes.
• Grading and drainage plan – especially important near floodplains and slopes.
• Erosion and sediment control plan for construction – silt fencing, stabilized entrance, and so on.
• Geotechnical report – for slope stability, unstable soils, or foundations near hazards.
• Hydrology / hydraulic analysis – if flooding impacts need to be assessed.
• Wetland or environmental studies – if wetlands or shoreline features are involved.

Yes, it can feel like a lot. But compare it to the alternative: building in a hazard area without understanding the risk. That is how people end up with a gorgeous new home and a seasonal indoor swimming pool – not the fun kind.

Why people struggle with Conservation Authority approvals

When homeowners tell me “the Conservation Authority is impossible,” it is usually one of these:

1. They discovered the CA too late

   Learn about CA permissions after you have paid for final drawings and you may be forced into a redesign – a bigger setback from a bank, different grading, a different driveway location. It feels like the goalposts moved. Really, you started playing before you read the rules.

2. They assumed “small work” doesn’t matter

   Fill, re-grading, retaining walls, shoreline “tidying,” and culverts can all change how water moves – which is exactly why CAs exist. “It’s just a little fill” is not a magic phrase that makes regulation disappear.

3. They didn’t budget for studies

   Technical studies cost money. Skip planning for them and the CA feels like it “added extra costs.” The real fix is budgeting for due diligence when you buy the lot, especially near water or slopes.

4. They submitted an incomplete package

   This is the big one. Missing elevations, missing grades, unclear drawings, or outdated plans are what drag files out. CAs cannot approve vibes – they approve evidence.

5. They expected the CA to design the solution

   CA staff can tell you what they need to see. They generally will not design your grading plan, your slope stabilization, or your stormwater strategy – that is your designer/engineer’s job. Show up with “what should I do?” and you get guidance. Show up with “here is my proposal and here is why it is safe” and you move faster.

How to make CA approvals simpler (a homeowner playbook)

Here is the process I recommend when someone wants a “simple guide” that actually works on real Ontario projects:

Questions to ask at your first CA conversation

If you want to sound like someone who has done this before (without actually having to suffer first), ask these:

• Is the proposed work in a regulated area, and which hazard or feature is driving it – flooding, erosion, wetland, shoreline, or watercourse?
• What is the minimum safe or required setback from the feature or hazard?
• Do you need a topo survey, grading plan, geotech, or hydrology study for this proposal?
• Is this likely considered minor or major, and what are your service standards once the application is complete?
• Are there common conditions you apply – erosion controls, construction timing, vegetation protection?

Those questions keep the conversation factual. They also stop you from falling into the classic trap of arguing with the existence of water.

“My municipality says I need CA clearance” – what that means

Municipal building departments often will not issue a building permit until they have confirmation that CA requirements are satisfied, when applicable. That does not mean the CA is “taking over” your building permit. It means the municipality is managing risk and following the process: hazard-related permissions first, then the building permit. The CA is not checking your kitchen layout – it is checking whether your site work will be safe and will not create impacts. For the bigger picture on how the pieces fit, see how to get a building permit in Ontario and how long a permit really takes.

What about hearings, appeals, or “escalation”?

Most files never get dramatic. They get approved with conditions once the technical pieces are in place. But if you hit a wall – especially around timelines – some CAs describe an administrative review process when decisions are not made within the required timeframe. The right move is usually to stay professional, document everything, and ask what the next step is under their process.

That said: if your proposal truly increases flood risk, destabilizes a slope, or interferes with a wetland in a way that cannot be supported, a refusal is possible. The “solution” in those cases is usually a redesign – setback, elevation, grading, or a different location – not louder emails.

Costs: what to budget for (without pretending there’s one number)

There are two cost buckets to expect, and the pain almost always comes from surprise, not the number itself:

• CA application fees – these vary by Conservation Authority and by application type and complexity.
• Technical work – survey, engineering, geotech, hydrology, and design time to produce the drawings and reports that prove safety.

If you buy near water or a valley, budget for extra due diligence from day one and you will feel a lot less ambushed. Roll it into your overall numbers with the full cost of building and your lot prep with the land development cost calculator so nothing lands as a spring surprise.

Final reality check: treat CA requirements like a design input

Homeowners who succeed with Conservation Authority approvals do one thing differently: they treat CA requirements like a design factor, not a nuisance. Once you accept that your lot has a water story – flood, slope, wetland, or shoreline – you design the home and the site to fit that story. That is not red tape. That is long-term safety and durability.

And if you are wondering why the CA cares about your little project: water does not stop at your lot line. The whole watershed is connected. Change how water moves on your property and it can change how water behaves on your neighbour’s. CAs are there to keep that from becoming a community-wide headache. So do not wait for the building-permit stage to discover Conservation Authority approvals – start early, get a clear list of required studies, and submit a complete package. You will save time, money, and a surprising amount of mental health.

Related permit guides on this site

Conservation Authority approvals: frequently asked questions

Note: general guidance, not a ruling on your project. Regulated areas, required studies, fees, and service standards vary by Conservation Authority and by site. Confirm with the CA that covers your watershed – or have us pull the mapping and scope it for you.