Septic System Rules in Ontario: Permits, Setbacks and Who Approves What

Septic systems in Ontario are regulated mainly through the Building Code, with the province, municipalities and conservation authorities each covering a piece. The rules exist to keep sewage out of wells, lakes and creeks, and most of them come down to three questions: is the design right for the site, is it far enough from water and buildings, and was it built by qualified people and inspected before it was buried. This guide explains each layer in plain terms. It is general information, not legal advice; your designer and building department confirm what applies to your lot.

Who regulates what

• The Ontario Building Code (O. Reg. 332/12), Part 8, governs on-site sewage systems with a design daily flow of up to 10,000 litres on a single lot. That covers virtually every house, cottage and small business on septic.
• The Ministry of the Environment, Conservation and Parks approves larger systems, and those serving more than one lot, through an Environmental Compliance Approval under the Ontario Water Resources Act.
• Hauled sewage, the material pumpers remove, is regulated by the same ministry under the Environmental Protection Act. Haulers need provincial approval to carry it.
• Local building departments issue permits and inspect Part 8 systems.
• Conservation authorities regulate development in floodplains, wetlands, shorelines and valleys, which can include a new septic bed.

Before 1998, septic approvals in Ontario came under environmental legislation and were often handled by health units or the province. When they moved into the Building Code, permits shifted to municipalities, which is why records for older systems can be scattered.

Where to get a permit around Hamilton

A permit is required to build, replace or alter a Class 4 or Class 5 system. Who issues it depends on where the property is:

• City of Hamilton: the Building Division, for rural properties across the city, including Flamborough, Glanbrook, Ancaster, Dundas and Stoney Creek.
• Haldimand County: the County’s building department, covering Caledonia, Hagersville, Cayuga, Dunnville, Jarvis and the lakeshore.
• West Lincoln, Grimsby and Lincoln: Niagara Region runs the sewage system permit program for these municipalities.
• County of Brant: the County’s building department. Most of the City of Brantford is on municipal sewers.
• Norfolk County: the County’s building department, including the Lake Erie shoreline communities.

Many building departments also review the existing septic system when you apply to add bedrooms, finish a basement or build an addition, because more living space can mean more wastewater than the original design allowed for. Ask about this before you draw up renovation plans. Minor repairs, such as replacing a baffle or a pump, may not need a permit; replacing a tank or bed almost always does. When in doubt, call the permit office first.

Who may design and install a system

Ontario regulates the people as well as the systems. A septic system design must be prepared by someone who holds the Building Code qualification for on-site sewage systems and is registered with the Ministry of Municipal Affairs and Housing, usually identified by a Building Code Identification Number (BCIN), or by a professional engineer. Firms that design or install systems for others generally must be registered too, with qualified staff doing or supervising the work.

When you hire, ask for the designer’s and installer’s registration details and check that the permit application lists them. Registered professionals are accountable for their work under the Code, and the building department will expect their names on the documents.

Typical clearance distances

The Building Code tables set minimum horizontal distances between parts of a sewage system and things that need protecting. The figures below are typical minimums from the Building Code tables; your designer confirms them for your lot, since special cases and local conditions change the answer.

Septic tank

• About 15 metres (49 feet) from a drilled or dug well
• About 15 metres from a lake, river, pond or stream
• About 1.5 metres (5 feet) from a building or structure
• About 3 metres (10 feet) from a property line

Leaching bed

• About 15 metres from a well with a watertight casing deeper than 6 metres (20 feet)
• About 30 metres (98 feet) from any other well
• About 15 metres from a lake, river, pond or stream
• About 5 metres (16 feet) from a building or structure
• About 3 metres from a property line

Remember that distances run both ways. Your neighbour’s well limits where your bed can go, and a pool, garage or addition you build later must respect the bed. These setbacks are often what pushes a small lot toward a treatment unit or a holding tank; see holding tank vs septic tank.

Conservation authority permits

If your property includes or borders a floodplain, wetland, shoreline, steep slope or watercourse, it may be within an area regulated by a conservation authority, and building a new septic system there can need that authority’s permission as well as a building permit. Around Hamilton the relevant authorities include Hamilton Conservation Authority, the Grand River Conservation Authority, the Niagara Peninsula Conservation Authority and the Long Point Region Conservation Authority, with Conservation Halton covering parts of north Flamborough. Which one applies depends on the watershed your property drains to, and the building department will usually tell you if a clearance is needed.

Maintenance inspections and ongoing obligations

The Code expects systems to be operated and maintained so they work as designed, and treatment units must be serviced under an ongoing agreement. Municipalities can choose to run maintenance inspection programs, and under the Clean Water Act some systems close to municipal drinking water sources must be inspected on a regular cycle as part of a local source protection plan. Programs differ from place to place; your building department can tell you whether your property is covered.

When an old tank is taken out of service it must be properly decommissioned, usually pumped and then removed or filled so it cannot collapse. A building department can also order an owner to fix a system that is discharging sewage to the surface or otherwise failing.

Putting the rules to work

In practice, a qualified designer and installer handle most of this paperwork for you, and a good one will tell you early if your lot needs a conservation authority clearance or a treatment unit. To get started, send one request and we will pass it to a licensed local contractor who works with your building department. The septic installation and septic bed replacement pages explain the build itself, and the cost guide covers what it is likely to cost.