Stale numbers

Toronto's basement flooding subsidy went up, and most pages did not notice

There is a specific way that a helpful page becomes a harmful one, and it does not involve anybody lying. The page was accurate when it was written, the programme it describes changed, and nothing about the page announces that it is now out of date. A reader has no way to tell the difference between a current figure and a superseded one.

Toronto’s basement flooding subsidy is a live example, and it is worth walking through because the pattern repeats across every municipal programme on this site.

What the number is now

The City of Toronto’s Basement Flooding Protection Subsidy Program pays up to $6,650 per property for work completed on or after 12 November 2025. The City’s own page carried a modified date of 18 June 2026 when we read it on 20 September 2026.

It is not one pot. It is a set of per-device maximums:

Two of those line items are more interesting than the headline.

Two backwater valves are fundable. A house with separate storm and sanitary laterals may need a valve on each, and any advice built on the assumption of one valve per house under-scopes that property by $1,600.

The battery backup is separately funded. A sump pump keeps a basement dry by running. The storm big enough to overwhelm a drainage system is frequently the storm that takes the power out, at which point a sump pump on mains power alone stops at precisely the wrong moment. The City funding the backup as its own line item is that observation expressed as budget.

Why Toronto specifically

The programme is shaped by what is under the street. The City publishes that approximately 23 per cent of its older areas are served by combined sewers — a single pipe carrying both sewage and stormwater, in places built as much as a century ago. It maintains nearly 3,800 kilometres of sanitary sewers and more than 523,000 City-owned sewer service line connections.

In a combined system, a heavy rainfall and a sewage backup are not two events that might coincide on the same night. They are one event. Which is why the City’s conditions are written the way they are.

The conditions that are done first

This is where applications actually fail, and it is not the paperwork.

Your downspouts must already be disconnected from the sewer. Not planned. Done. In a combined-sewer city every downspout still discharging into the sewer is adding rainwater to the pipe that is about to surcharge into somebody’s basement, so the City treats disconnection as the precondition rather than as an extra.

Any paved front-yard area must comply with the City’s zoning requirements. Same logic: impermeable front yards send water to the same place.

A building permit is required to install a backwater valve. Not retroactive.

Then the ones checked afterwards: your contractor must have held a valid City of Toronto business licence at the time of the work, you apply within two years of installation, and you must have no outstanding taxes or debts to the City.

The working order, then, is: downspouts and front yard, permit, work, application. Any other order is how the money gets left on the table.

How to tell whether a page you are reading is stale

This applies to every municipal programme, not just Toronto’s.

1. Look for an effective date, not a publication date. Toronto’s amounts attach to work completed on or after a specific day. A page that gives you a figure with no date attached to the figure cannot be checked.
2. Look for a link to the city. If the only place the number exists is the page you are on, there is nothing to verify it against.
3. Check whether the line items are listed. A page that gives only the headline maximum has usually copied the headline maximum from somewhere else.
4. Ottawa is the easy case. Its amounts are set by Residential Protective Plumbing By-law No. 2025-89, approved 26 February 2025 and in force from 1 April 2025. A named, dated by-law is the gold standard for checkability, and anything written before that date is describing the old programme.

And the thing the subsidy does not do

Every dollar of this pays for a device that reduces the chance of water arriving. None of it pays for the damage if it arrives anyway.

The Insurance Bureau of Canada is unambiguous that water damage in a basement due to a sewer backup is only covered if you have purchased specific, optional sewer backup coverage. The devices and the endorsement are complements, not alternatives, and doing one while assuming it covers the other is the most common expensive mistake in this whole subject.

Our Toronto page has the current line items with the City’s page linked, and the sewer backup endorsement page has the seven questions worth asking before you add the cover.

The same trap, in the other three cities

Toronto is the clearest example because the change is recent and the numbers are large, but each of the other municipalities on this site has its own version of the problem, and they fail differently.

Mississauga publishes a maximum of $7,500, which is the largest headline of the four and the most misleading if you stop at the headline. The programme is two mutually exclusive options: a sump pump route paying to $6,000 with $1,000 for foundation drain pipe capping, or a storm lateral backwater valve route paying to $1,500. No single household reaches $7,500 by doing everything, because you cannot do everything. Any page that reports “up to $7,500” and stops has told you something true and left out the part that decides whether it applies to you.

There is a second trap in Mississauga that has nothing to do with staleness: the Region of Peel runs a separate rebate, paying 60 per cent of the invoiced amount to a maximum of $1,500 including tax, for a valve on the sanitary lateral. The City’s backwater valve option covers the storm lateral. Two governments, two pipes, two applications. A homeowner who claims one and assumes they are finished has protected half the problem.

Ottawa is the easiest to verify and therefore the easiest to catch out. Its amounts are $2,500 for an exterior storm backwater valve, $1,500 for a sump pump in an existing pit and $3,000 for a sump pump in a new pit — and they are set by Residential Protective Plumbing By-law No. 2025-89, approved 26 February 2025 and in force from 1 April 2025. Anything written before that date describes the previous programme. The City also fully rebates the building permit fee on submission of the permit and the inspection report, which is a real amount of money that almost nobody mentions.

Hamilton pays the least, at $2,000, and the number that actually matters there is not the maximum at all. The grant falls to $500 for a backwater valve if you use a contractor from outside the City’s pre-qualified list. That is a $1,500 swing decided entirely by which company holds the wrench, and it is the single most consequential fact about that programme. A page reporting “Hamilton pays up to $2,000” without the contractor condition is not stale — it is just incomplete in a way that can cost a reader $1,500.

Why we rebuild these pages instead of editing them

The failure mode described at the top of this post is not carelessness. It is structural: a page written by hand contains a number that has no connection to the source it came from, so when the source changes nothing on the page knows.

Every municipal figure on this site lives in a single file with the document it was read from and the date it was read, and the pages are regenerated from that file rather than edited in place. When Toronto changes its amounts again — and it will — the change happens in one place and every page that mentions it moves together, including the comparison chart, the city selector and the machine-readable summary.

That does not make us right. It makes us checkable, which is the most any publisher of other people’s numbers can honestly offer. The methodology page sets out what we read, when, and the list of things we deliberately do not publish because nobody measured them.

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