Regions
Every Ontario region we cover
All 41 Ontario regions with significant rural on-site sewage activity. Each page covers the local ground — Shield rock, heavy clay plains, moraine sand — what that means for system class and price, and how to get quotes from installers who work there.
| Region | Type | Typical ground |
|---|---|---|
| Durham Region | Regional Municipality | Well-drained moraine soils in the north |
| York Region | Regional Municipality | Sand and gravel on the moraine |
| Peel Region | Regional Municipality | Sandy moraine soils on the ridge, stony till on the slopes, occasional clay pockets in the valleys. |
| Halton Region | Regional Municipality | Thin soils over dolostone on Escarpment benches, stony loam till elsewhere, sand and gravel on moraine stretches. |
| Hamilton | Single-tier Municipality | Thin soils over dolostone on the mountain top, stony till below, clay flats in the southeast. |
| Niagara Region | Regional Municipality | Heavy lacustrine clay dominates the south |
| Waterloo Region | Regional Municipality | Stony loam till, sand and gravel moraine pockets, clay loams in the valleys. |
| Wellington County | Upper-tier Municipality | Loam till over limestone/dolostone |
| Simcoe County | Upper-tier Municipality | Loam till, sandy outwash near Wasaga and along river valleys, clay pockets near Nottawasaga Bay. |
| Middlesex County | Upper-tier Municipality | Fine-grained clay-loam till dominant — slow percolation is the normal starting assumption. |
| Essex County | Upper-tier Municipality | Heavy Brookston clay with perched seasonal water tables |
| City of Ottawa | Single-tier Municipality | Leda clay in the east (sensitive to loading), thin limestone soils in West Carleton, sands in Cumberland. |
| Kawartha Lakes | Single-tier Municipality | Thin soils over bedrock in northern and lake townships |
| Peterborough County | Upper-tier Municipality | Deep till in the south |
| Northumberland County | Upper-tier Municipality | Clay-loam till near the lake, sandy moraine soils in Hamilton Township's north, thin ground toward Alderville. |
| Prince Edward County | Single-tier Municipality | Thin soils over limestone bedrock |
| Hastings County | Upper-tier Municipality | Clay and till in the south |
| Lennox & Addington County | Upper-tier Municipality | Limestone-derived loams and clay flats in the south |
| Frontenac County | Upper-tier Municipality | Very thin soils, rocky outcrops, organic lake-bottom sediments in the low spots. |
| Leeds & Grenville | Upper-tier Municipality | Shallow rocky soils along the St. Lawrence |
| Prescott & Russell | Upper-tier Municipality | Deep, heavy clay — among Ontario's most challenging natural percolation conditions. |
| Stormont, Dundas & Glengarry | Upper-tier Municipality | Heavy lacustrine clay with slow internal drainage |
| Renfrew County | Upper-tier Municipality | Thin rocky soils on the uplands |
| Lanark County | Upper-tier Municipality | Thin soils over bedrock with glacial till pockets |
| County of Brant | Single-tier Municipality | Loam till on the slopes, coarse sands around Burford, clay-loam near the river flats. |
| Norfolk County | Single-tier Municipality | Deep sands and sandy loams: fast percolation but a shallow, easily contaminated water table. |
| Oxford County | Upper-tier Municipality | Clay-loam till dominant, with sand pockets near Tillsonburg and Norwich. |
| Elgin County | Upper-tier Municipality | Clay-loam till with beach-ridge sands along the ancient shorelines. |
| Chatham-Kent | Single-tier Municipality | Deep Brookston-type clay |
| Lambton County | Upper-tier Municipality | Heavy clay in the county's centre and south |
| Huron County | Upper-tier Municipality | Clay-loam till with beach sands at Grand Bend and Bayfield's fringe. |
| Perth County | Upper-tier Municipality | Clay-loam till, poorly drained flats, gravelly knolls near Milverton. |
| Grey County | Upper-tier Municipality | Thin soils over dolostone on the Escarpment, stony loam till on the plateaus, clays in the Beaver Valley floor. |
| Bruce County | Upper-tier Municipality | Very thin soils over limestone with karst features up the peninsula |
| Dufferin County | Upper-tier Municipality | Stony loam till, moraine sands in Mono and Amaranth, clay pockets in East Garafraxa. |
| Muskoka District | District Municipality | Thin glacial scrape, rocky outcrops, organic sediments in bays and lowlands. |
| Haliburton County | Upper-tier Municipality | The thinnest natural soils in central Ontario |
| Parry Sound District | District Municipality | Thin-to-absent soils over granite |
| Nipissing District | District | Nipissing clays around the lake plain, thin rocky soils inland. |
| Sudbury District | District | Thin soils over rock, extensive wetland organics, limited workable ground. |
| Thunder Bay District | District | Thin soils over Canadian Shield bedrock |