waterdamagequotesToronto · the valve on the old streets
Backwater valve installation in Toronto: the subsidy, the permitted type, and the permit
A backwater valve is the device Toronto most wants in older houses, and the one it pays most towards: up to $1,600 per valve, for up to two valves. It is also the device with the most rules attached — which type is allowed, the permit, what you must not do while it is closed — and the one most often priced against subsidy figures that no longer apply.
This page sets out what Toronto pays towards a backwater valve and how the 80 per cent rule works on real invoice amounts, the only valve type the City permits, the permit, why Toronto’s older neighbourhoods are the ones the programme was built for, what a valve installation costs where anyone in Ontario publishes it, and how to live with one. The whole programme is on Toronto basement flooding; valves in general are on backwater valves.
The short version
- Toronto pays 80% of the invoice up to $1,600 per backwater valve, for a maximum of two devices, on work completed on or after November 12, 2025.
- Only a fullport, normally open valve may go in a building drain serving one occupancy; a normally closed valve is prohibited.
- A building permit is required for the valve, and it is a condition of the subsidy.
- Pages that still give $1,250 or a $3,400 programme maximum are quoting the programme that ended.
What Toronto pays towards a backwater valve
| Item | Maximum | Note |
|---|---|---|
| Home plumbing assessment | $500 | One assessment per property. |
| Backwater valve | $1,600 per device | Maximum two devices. |
| Sump pump | $2,250 | Maximum one device. |
| Sump pump battery backup | $300 | Covers the power failure case, which is the one that actually floods basements during a storm. |
| Pipe severance and capping | $400 |
City of Toronto, Basement Flooding Protection Subsidy Program · 2025
These are the amounts that apply to work completed on or after November 12, 2025. Pages still quoting Toronto's older, smaller maximum are quoting a programme that no longer exists. The City's page carried a modified date of June 18, 2026 when it was read.
City of Toronto, Basement Flooding Protection Subsidy Program · 2025
The backwater valve allowance for work completed BEFORE 12 November 2025. The City still publishes it alongside the current figure, because work done then is still claimable under it.
The valve line is the largest per-device amount in the programme, and the only one that allows two devices. The programme total across every line is $6,650. Work completed before November 12, 2025 is still claimable, at the old allowance of $1,250 for one valve — which is why that figure survives on contractor pages long after it stopped applying to new work.
City of Toronto, news release, April 28, 2026 · 2026
The maximum before the expansion. The City described the change as almost doubling the amount of basement flooding subsidies. Any page still quoting $3,400 is describing the programme that ended.
The 80 per cent rule on a real invoice
| Invoice for one valve | 80% of invoice | City pays | You pay |
|---|---|---|---|
| $1,200 | $960 | $960 | $240 |
| $1,800 | $1,440 | $1,440 | $360 |
| $2,000 | $1,600 | $1,600 | $400 |
| $2,600 | $2,080 | $1,600 | $1,000 |
City of Toronto, Basement Flooding Protection Subsidy Program · 2025
Every line of the Toronto programme is capped twice — at this share of the invoice AND at the dollar maximum for that device. A $1,600 backwater valve allowance does not mean $1,600 arrives; it means 80 per cent of the invoice up to $1,600. Our first pass published the dollar caps without this, which overstates what a homeowner gets back.
The cap binds at an invoice of $2,000: below it, the City pays 80 per cent; above it, every extra dollar is yours. So a $1,600 allowance does not mean $1,600 arrives on a $1,200 job — $960 does. Ask for the valve to be itemized separately from the home plumbing assessment and any severance, because each line is capped on its own.
The only type Toronto allows
City of Toronto, Building permit application guide — Backwater valve · 2026
The same guide states that a valve “designed to be installed in a normally closed position is prohibited from being installed in a building drain or building sewer”. So the federal page describes two types and Toronto permits one of them. Page last modified July 14, 2026.
Government of Canada, Get Prepared — Backwater valves · 2026
The federal page adds that the one-way valve “allows wastewater to flow out of your home, and securely closes when backups or backflow is detected”, and that they are also called sewer backflow valves. Page last modified March 23, 2026.
The federal guidance describes two kinds of valve: normally open, which lets wastewater out until backflow closes it, and normally closed, which opens only to let wastewater out. Toronto’s building permit guide permits the first and prohibits the second in a building drain or building sewer. A quote that does not name the valve type and its CSA standard is a quote to ask about before signing.
The permit, and the other conditions
City of Toronto, Building permit application guide — Backwater valve · 2026
The City's plumbing fee line for “Backwater Valves, Manholes, Catchbasins, Interceptors and Sumps Complete with Pumps”. It is a per-item fee inside a standalone drain permit application, not the whole cost of permitting the job — compare Hamilton, which publishes a $291 building permit fee for the same device.
- You are the registered owner of a single-family, duplex, triplex or fourplex in Toronto.
- Your downspouts are disconnected from the sewer system.
- Any paved front-yard area complies with the City's zoning requirements.
- You apply within two years of installation.
- Your contractor held a valid City of Toronto business licence at the time of the work.
- You have no outstanding taxes or debts to the City.
- You obtain a building permit to install a backwater valve.
The permit is two things at once: a building code requirement for the work and a condition of the subsidy. The other conditions that catch valve applications are the same as for every line — a contractor with a valid City of Toronto business licence at the time of the work, disconnected downspouts, and an application within two years. And the lifetime maximum follows the property:
City of Toronto, Basement Flooding Protection Subsidy Program · 2026
The cap attaches to the property, not to the owner, so a previous owner’s claim can reduce or exhaust yours. The City will check a property’s subsidy history on request — the contact is on its own page, linked here.
Why Toronto’s older streets
City of Toronto, The Sewers on the Street · 2026
The share of the City's older areas served by combined sewers — one pipe carrying both sewage and stormwater, in places built as much as a century ago. In a combined system a heavy rainfall and a sewage backup are the same event.
In the parts of the city built on combined sewers, one pipe carries both sewage and stormwater, so a heavy rainfall and a sewage backup are the same event. That is the house the backwater valve was designed for: when the combined sewer surcharges, the valve closes and the basement floor drain stays dry. The City’s first instruction after a backup is still to report it to 311:
City of Toronto, Blocked or Backed-Up Basement Drain · 2026
Page modified May 11, 2026; the City marks the four hours with an asterisk. The instruction is to report a blocked sewer service line or basement flooding to 311. The technician first investigates the City-side portion of the line using closed-circuit TV; if the City side is clear, the problem is on the private side and the owner is advised to call a licensed plumber.
What an installation costs
No public body publishes a Toronto installation price, and the Toronto contractor pages read for this page quote subsidy figures, not prices. The only measured installed price for a backwater valve in Ontario that this site has found is Hamilton’s, where the City publishes what its pre-qualified contractors charge:
City of Hamilton, Protective Plumbing Program, pre-qualified contractor fee table · 2026
The adapt-a-valve variant runs from $1,292 to $2,505 plus HST across the same five firms. The building permit is $291 and downspout disconnection is $75 plus HST per downspout. Five firms is a small sample and it is one city, and this site says so rather than calling it a national average.
Set against Toronto’s rule, an invoice in that range sits below the $2,000 point where the cap binds, so the City’s 80 per cent applies in full. Toronto prices may differ from Hamilton’s; the useful point is the shape of the bill — an assessment, the valve, the permit — and that each line is subsidized separately. The federal government’s figure for what a flooded basement costs to repair is the comparison the programme is betting on:
Government of Canada, Get Prepared — Backwater valves · 2026
The federal page's figure for the average cost to repair a flooded basement, which it says could also impact your insurance premium. It is the only average repair figure on this site with a government source, and it is a national average rather than a quote for your basement.
Living with a valve
City of Toronto, Basement Flooding Protection Subsidy Program · 2026
The failure mode nobody warns you about when they sell you the valve: the device works, and then the household floods itself from the inside. It is why the alarm is worth more than it costs.
Government of Canada, Get Prepared — Backwater valves · 2026
The federal page's reason for wanting one: it “will help you avoid causing a ‘self-flood’ by using excess water when the valve is closed”. Toronto, Ottawa, Peel and EPCOR all publish the same instruction in different words — when the valve is shut, stop using water.
City of Toronto, Basement Flooding Protection Subsidy Program · 2026
Toronto's subsidy conditions also say not to enclose or cover the valve before the inspection is complete — a finished basement built over an unlocated valve is a common and expensive way to lose access to it.
Government of Canada, Get Prepared — Backwater valves · 2026
The cleaning steps end with a warning that is easy to miss: “Tightly secure the cap. Backwater valves can fail if the cleanout cap is not secure.”
A closed valve protects the basement from the sewer and does nothing for water the house sends down its own drains — which then has nowhere to go but the floor drain. That is the case for an alarm, for telling everyone in the house what it means, and for keeping the access cover reachable: Toronto’s conditions say not to enclose or cover the valve before inspection, and a finished floor over it makes the twice-yearly cleaning the federal guidance asks for impossible. A valve does not replace insurance: sewer backup cover is an optional endorsement.
Insurance Bureau of Canada, Water Damage and Flood Protection · 2026
IBC's wording is unambiguous: “Damage caused by the backing up of sewers and drains is typically not covered by a standard policy.” It adds that “optional sewer backup is offered by most insurers” — so the cover exists, it is just not switched on by default.
Why this site has nothing to gain from your answer. We are paid a fixed amount for each enquiry, agreed before it is sent. It does not move with the size of the job, with whether you book anything, or with which company you pick. So there is no version of this page where steering you is worth anything to us — which is also why you will not find a company named, rated or recommended anywhere on this site.
Questions people actually ask
How much does Toronto pay for a backwater valve?
Up to 80% of the invoiced cost to a maximum of $1,600 per device, for a maximum of two devices, for work completed on or after November 12, 2025. For earlier work the allowance was $1,250 for one device.
What type of backwater valve is allowed in Toronto?
A fullport (normally open) backwater valve conforming to the appropriate CSA standard, in a building drain serving only one occupancy. Toronto's permit guide says a valve designed to be installed in a normally closed position is prohibited.
Do I need a permit for a backwater valve in Toronto?
Yes. A building permit is required to install a backwater valve, and it is a condition of the subsidy. The City's plumbing fee line for backwater valves is $38.67 each.
How much does a backwater valve installation cost?
No public body publishes a Toronto price. Hamilton publishes what its pre-qualified contractors charge: $1,292 to $1,562 plus HST for an assessment and a mainline backwater valve.
Is the Toronto backwater valve rebate still $1,250?
Only for work completed before November 12, 2025. For later work it is up to $1,600 per device, maximum two, and the programme maximum is $6,650 rather than $3,400.
Can I use the toilet when the backwater valve is closed?
No. Toronto says that when the valve is closed, do not use any plumbing fixtures, as water will not drain and will back up into your home.
Where to read next
- Toronto basement flooding: the whole programme
- Backwater valves across Canada
- Toronto’s sump pump subsidy
- Why the old figures persist
- Valve and sump maintenance
Sources cited on this page
- City of Toronto, Basement Flooding Protection Subsidy Program
- City of Toronto, news release, April 28, 2026
- City of Toronto, Building permit application guide — Backwater valve
- Government of Canada, Get Prepared — Backwater valves
- City of Toronto, The Sewers on the Street
- City of Toronto, Blocked or Backed-Up Basement Drain
- City of Hamilton, Protective Plumbing Program, pre-qualified contractor fee table
- Insurance Bureau of Canada, Water Damage and Flood Protection
Every figure above was read from the source it is attributed to on September 20, 2026. How we check this.
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