If you want to split your property in Kawartha Lakes, the septic question gets settled before the severance does. Both pieces of land have to demonstrate they can treat sewage on their own, and the existing system almost never counts for both.
That single requirement is what stalls or kills most rural consent applications around here. People budget for the survey and the application fee, then discover the retained lot’s leaching bed sits three metres inside the proposed new lot line, and the whole plan has to be redrawn.
Here’s what the septic side of a severance actually involves, what it costs, and how to find out early whether your lot can be split at all. If you want your existing system located and assessed before you spend money on a survey, call (705) 702-5526 or book a visit.
The Quick Answer
| What the approval authority wants | On the new (severed) lot | On the retained lot |
|---|---|---|
| Proof of sewage treatment | A soil evaluation showing a Class 4 system can be built | An existing system that is legal, functional, and entirely on the retained lot |
| Setback compliance | Bed and tank clear of the new lot lines, wells, and water | Same, measured against the new boundary |
| Records | Site plan and soil report from a qualified designer | Original permit if it exists, or an inspection report if it doesn’t |
| Typical septic-side cost | $2,000-$4,000 for evaluation and design | $300-$500 for a full inspection, more if the system has to move |
| Typical septic-side timeline | 4-10 weeks, longer if the ground is frozen | 1-3 weeks for an inspection |
Two facts do most of the damage. First, a soil evaluation can’t be done on frozen ground, so a January application often waits until April. Second, if the existing bed straddles the proposed line, moving it is a full replacement at $15,000 to $35,000, and that cost lands before you have a buyer.
Why the Existing System Rarely Covers Both Lots
A septic system is licensed to serve one dwelling on one parcel. When you draw a new line through the property, the approval authority looks at where the tank and the leaching bed physically sit, and asks a simple question: is the whole system on the lot it serves?
If the answer is no, you have three options, and none of them are cheap.
You can redraw the severance line so the system stays intact on the retained lot. This is the cheapest fix and the one people reach for, but it only works if the resulting lots still meet minimum frontage and area requirements.
You can move the system. That’s a new bed, a new permit, and usually a new tank, because a tank that’s already 25 years old isn’t worth relocating. See our breakdown of what a full septic replacement costs in Ontario.
Or you can grant an easement so the retained lot’s system stays where it is on land that now belongs to someone else. Approval authorities dislike this, buyers dislike it more, and it will show up on the title of both properties forever.
A property owner near Lindsay went through exactly this in 2025. The plan was to sever a two-acre building lot off the back of a ten-acre parcel. The house’s leaching bed turned out to be 40 years old, undocumented, and sitting almost exactly on the proposed line. Redrawing the lot line cost them nothing but a revised survey. Discovering it after the application would have cost them a $22,000 relocation.
Step One: Find Out Where Your System Actually Is
Before you pay for anything else, find the tank and the bed. On rural properties in the Kawarthas, roughly half the systems installed before the 1990s have no usable record at the municipal office, and the owner’s memory of where things are is often off by ten metres or more.
A locate is not expensive. It usually happens as part of a routine visit, and if the tank has to be pumped anyway, a standard pump-out runs $300 to $600 for a 1,000 to 1,500-gallon tank. Our cost calculator will give you a number for your specific tank.
What you want out of that visit is three things: the tank location marked, the bed extent marked, and an honest read on the system’s condition. Take photographs with a fixed reference point in frame, like a corner of the house. Your surveyor will thank you.
Do not go looking for the tank yourself by opening lids. Septic gases can incapacitate a person in seconds, and a deteriorated concrete lid will hold a lawnmower and then fail under a person. Our guide on how to find your septic tank covers the safe methods.
Step Two: The Soil Evaluation on the New Lot
The severed lot has to prove it can support a system. That means a qualified designer digs test pits, logs the soil profile, and often runs a percolation test to measure how fast water moves through the ground.
What they’re looking for is usable soil depth above bedrock or the water table, and a percolation rate that a conventional bed can work with. Around the Kawarthas, two things routinely come back badly: shallow soil over limestone, and high seasonal water tables near the lakes and the wetland fringes.
Neither is automatically fatal. Poor soil pushes you toward a raised bed or a treatment unit, both of which are more expensive to build. Our guide to Ontario septic classes explains what each option involves, and vacant land septic feasibility covers the same ground from a buyer’s perspective.
Budget $500 to $1,500 for the perc test and soil work, and $1,500 to $3,500 for the designer. If the site needs a specialty study, hydrogeology on a constrained waterfront lot for example, that’s a separate cost.
Step Three: The Permit Comes Later, Not Now
A common misreading: people think they need a septic permit to get the severance. They don’t. What the consent process wants at this stage is evidence that a compliant system can be built, not a built system.
The actual permit comes when someone applies to build on the new lot. In Kawartha Lakes that fee runs $500 to $800 for a standard residential system, and the full permitting and design package before any digging starts typically totals $3,000 to $7,000. Our septic permit guide walks through the sequence.
The reason this matters for your budget is timing. The evaluation money is spent up front and is not refundable if the severance is refused. The permit money is spent by whoever eventually builds, which may be the buyer rather than you.
What Trips People Up
Setbacks measured against the new line. Your bed might be 20 metres from the old boundary and 3 metres from the new one. Ontario Regulation 332/12 sets minimum clearances, and they apply to the boundary as it will exist, not as it exists today.
Wells on both lots. A new lot usually needs a new well, and a well has to keep its distance from every leaching bed nearby, including the neighbour’s and the retained lot’s. See how close is too close for the specifics. On a small severance this constraint alone can make the geometry impossible.
Winter. Soil evaluations need unfrozen ground. If you apply in November expecting a spring closing, the evaluation may not happen until April and the whole schedule slips a season.
Conservation authority review. Land near the lakes, the Trent-Severn system, or a regulated wetland may need Kawartha Conservation review on top of the municipal process, which adds fees and weeks.
The City’s Building and Septic Division is the right first call for the process questions. They will tell you what your specific parcel needs, and that conversation is free.
Frequently Asked Questions
Can I sever a lot if the existing septic system is old but still works?
Usually yes, as long as it’s entirely on the retained lot and it isn’t failing. Age alone doesn’t disqualify a system. What disqualifies it is effluent surfacing, a bed that no longer accepts flow, or a tank that’s structurally unsound. A full inspection at $300 to $500 will tell you which situation you’re in before an inspector hired by someone else does.
How much does the septic side of a severance cost in total?
Plan on $2,000 to $4,000 for soil evaluation and design work on the new lot, plus $300 to $500 to inspect and document the existing system on the retained lot. That’s the normal case. If the existing bed has to be relocated because of the new lot line, add $15,000 to $35,000 for a full replacement.
Do I need a septic permit before the severance is approved?
No. The consent process wants evidence that a compliant system can be built on the new lot, which means a soil evaluation and a design, not an issued permit. The permit is applied for later by whoever builds on the lot. Confirm the sequence with the City of Kawartha Lakes for your specific application.
What if the leaching bed crosses the proposed lot line?
You have three choices: move the line, move the bed, or register an easement. Moving the line is free if the lots still meet minimum size requirements. Moving the bed is a full system replacement. An easement keeps the system where it is but permanently encumbers both titles and makes the new lot harder to sell.
Can the soil evaluation be done in winter?
Not reliably. Test pits need unfrozen ground to give a readable soil profile, and percolation testing on frozen soil produces meaningless numbers. In the Kawarthas that generally means the window runs from mid-April to late November, depending on the year. Plan the application around it rather than fighting it.
Before You Spend Money on a Survey
The cheapest hour in a severance is the one where someone finds your existing tank and bed and tells you exactly where they sit. Everything downstream depends on it, and it costs a fraction of the survey you’re about to order.
Call (705) 702-5526 or book a visit. We serve every corner of the City of Kawartha Lakes with no travel surcharge and no minimum distance.