Raised septic beds for bedrock lots around Kingston
On the Canadian Shield and the limestone plain, the ground under your lawn runs out before the Building Code's soil depth does. A raised bed is how we build a septic system that works anyway.
Why Kingston-area lots end up with a mound
Part 8 of the Ontario Building Code requires about 900 mm of unsaturated, suitable soil between the bottom of a leaching bed and bedrock or the high water table. That depth is what treats the effluent before it reaches groundwater. Across South Frontenac, much of Loyalist Township, Greater Napanee's north and most of Prince Edward County, test pits hit rock well before that. The solution is to import the soil: a raised bed built on a pad of specified sand.
How a raised bed is built
- Strip and scarify: the topsoil comes off the bed area and the native surface is roughened so the sand bonds to it.
- Sand fill: clean, specified filter sand is placed and compacted in lifts to the depth the design calls for, often 600 to 900 mm.
- Stone and pipe: trenches of clear stone with perforated pipe (or chamber systems) are laid level in the sand, fed from the distribution box.
- Cover and shape: fill over the stone, then topsoil, graded to shed water, with sides at a mowable slope.
- Inspect and seed: inspected before cover, then seeded. The grass over a healthy raised bed looks like the rest of the lawn.
| Conventional in-ground bed | Raised bed | |
|---|---|---|
| Needs natural soil depth | 900 mm or more | Can be under 300 mm |
| Visible | No | Yes, a low mound |
| Imported material | Stone only | Sand (often 100+ tonnes) plus stone |
| 2026 installed range | $15,000 to $40,000 | $20,000 to $50,000 |
| Common around | Deeper clay and sand pockets | Sydenham, Verona, Inverary, Bath, PEC, rural Kingston |
Where even a raised bed won't fit, a filter bed or an advanced treatment unit lets the bed shrink. The system matcher gives a first read; a test pit gives the answer. Pricing is in the cost guide.
Who issues my septic permit?
Around Kingston it's not always the township. Pick where the property is.
Permits are issued under Part 8 of the Ontario Building Code by the "principal authority" for your area. We prepare and submit the application as part of every install.
Permit authority
Choose your area
The result names who issues the permit and what inspections to expect.
Get a raised bed quote
Send the property's town and what you need. If you're working to a closing date or a building permit deadline, say so and we'll prioritize. Answers from the tools on this page come through with the form.
Phone: 343-342-3461
Hours: Mon to Fri, 8 am to 5 pm
Office: 945 Princess Street, Kingston, ON K7L 3N6
Raised bed questions
What is a raised septic bed?
A leaching bed built above the natural grade on imported sand, used where there isn't enough natural soil depth over bedrock or the water table. The sand provides the treatment depth the Ontario Building Code requires; the mound you see is that sand plus the stone and pipe inside it.
Why do most Frontenac lots need a raised bed?
Because the Canadian Shield and Kingston's limestone plain often leave less than 900 mm of soil before rock. The Code requires a minimum depth of unsaturated soil beneath the bed, so the only way to get it is to build up.
How much does a raised septic bed cost?
In 2026, $20,000 to $50,000 installed in the Kingston area, before design and permit. The imported sand (often 100 tonnes or more) and the extra excavation are what put it above a conventional bed.
How big is the mound?
For a three-bedroom home, expect a mound roughly 15 to 25 metres long, 8 to 12 metres wide at the base and about a metre high at the centre, with sloped sides that can be seeded and mowed.
Can I landscape over a raised bed?
Grass, yes. No trees, shrubs with deep roots, vehicles, sheds, pools or hot tubs. Keep downspouts and sump discharge away from it.
Can a raised bed be built in winter?
Usually not well. Frozen sand doesn't compact properly. We schedule raised beds from late spring to late fall.