Seller's declaration: water pooling on the lot

Updated September 28, 2026

What question D3.6 asks

The OACIQ, Québec's real estate brokerage regulator, publishes the mandatory form “Declarations by the seller of the immovable” (English version V17 06/2022, French version V24 06/2022). Its section D3 covers the land. Under “To your knowledge”, question D3.6 asks: “Does water accumulate periodically on the land?” The seller ticks yes or no.

The answer covers what the seller knows. A “no” means that, to the seller's knowledge, water does not collect on the land periodically. It does not mean the seller never saw any, or that anyone checked and ruled it out.

When the buyer gets the form

According to the OACIQ, the broker must use this form, mandatory since July 2012, when signing a brokerage contract with an individual to sell a chiefly residential property of fewer than five dwellings. A condo (divided co-ownership) has its own form.

When the seller does not work with a broker, for example in a sale on DuProprio, this form does not come automatically. The OACIQ buyer's guide explains that your broker can then add a condition to the promise to purchase requiring the seller to fill it in. DuProprio offers its own seller's declaration; its question 3.5 also asks about periodic water accumulation on the lot. It is not the OACIQ form, though, and nothing requires the seller to fill it in. Ask which form the seller filled in, if any.

The form's other water questions

  • Flood zone (D2.9): among the restrictions of public law, “Immovable located in a flood risk area” (yes or no). To check this point, see our guide to the flood-zone map.
  • Backwater valve (D9.13): whether the building is equipped with a “backflow valve (to prevent sewer and rainwater backups)” (don't know, yes or no).
  • Sump, pump and French drain (D9.2 to D9.4): “a sump or a water retention pit”, a sump pump and a French drain.
  • Past infiltration and damage (D4.1, D14.1): water infiltration, and damage following events such as a flood.

A rain screening answers none of these questions. It does not say whether the building is in a regulated flood zone, whether it has a valve or what the seller has observed, and it does not cover the sewer backup that D9.13 is about. It shows where the water from a heavy downpour runs and collects around the address, which helps you prepare your questions about D3.6. A 100-year storm is rare by definition: the result does not say whether water collects on the lot periodically, which is what question D3.6 asks.

What to check during the visit

  1. The grading of the lot. The ground around the house should carry water away from the basement walls. Also check that walks, patios and driveways have not shifted so that water flows toward the house (Insurance Bureau of Canada).
  2. A reverse-slope driveway. Note whether the driveway slopes down below street level: it is then more vulnerable when water collects on the roadway. The City of Montréal suggests measures such as a watertight garage door, filling in the driveway or a removable flood barrier.
  3. Window wells. Look for water standing in the basement window wells (Insurance Bureau of Canada). CAA-Québec recommends a drained window well under basement windows that sit close to the ground.
  4. Downspouts. They should discharge onto a permeable surface, away from the foundation. In Montréal, it is prohibited to connect a downspout to the foundation drain or to point it at a hard surface or the street.
  5. The sump pit and pump. Ask whether there is one, and whether the pump has a backup battery. The City of Montréal notes that rain water from the lot and the foundation drain can damage a basement. It recommends a retention pit with a pump, on battery power if possible, since a power outage sometimes comes with violent storms.
  6. Backwater valves. According to the City of Montréal, each basement plumbing fixture (or group of fixtures) should have one, and it must stay accessible. They have been required in all new Montréal buildings since 2011. In some homes, flooring blocks access to them: ask the seller where they are.
  7. Signs of infiltration. CAA-Québec lists a persistent musty smell, mould, whitish crystals on concrete, recent stains, seeping walls and puddles on the floor. Outside: water that often collects near the house.
  8. Ditches and culverts along the street. Upkeep varies from town to town. In Terrebonne, it is shared: the culvert under the private driveway is the owner's responsibility, and replacing it needs a permit. In Vaudreuil-Dorion, an owner whose lot borders a roadside ditch maintains it from the road shoulder to the property line, across the full width of the lot.

When to check: before the offer or during the inspection period

Under clause 8.1 of the OACIQ promise to purchase (version V29 06/2022), the offer can be conditional on an inspection by a building inspector or a professional. The parties fill in the number of days; the form sets none. The buyer can also waive the inspection by initialling. If the inspection reveals a factor likely to reduce the building's value significantly, the buyer must notify the seller in writing, with the report, no later than the 4th day after the period ends, before 8 p.m.

The period starts on the day after acceptance and is counted in consecutive calendar days, weekends and holidays included. CAA-Québec recommends allowing 7 to 10 days, ideally: time to hold the inspection, receive the report and read it. DuProprio's offer to purchase template sets 10 consecutive days, which the parties can change by agreement.

That period is short. Before you make the offer, check the address on the official map (see our guide to the flood-zone map) and, if you wish, run a rain screening. The list above is for the visit, then for the inspection.

If something concerns you

  • Ask the seller in writing: when the water collected, where, and what has been done since.
  • Show the inspector the points you noted during the visit: grading, driveway, window wells, downspouts, sump pit, valves.
  • For lot drainage or the state of the foundation, consult an expert such as an engineer.
  • For the ditches, the culverts and any local maps, check with the municipality.

Sources

Check a house's address for $39

The check drops a 100-year, one-hour storm on the ground around the address and shows where the rain water collects. Result by email, no account.

You confirm the address on the next page, before paying $39.

See a sample result

Elsewhere on this site

These guides give general information, not legal, engineering or insurance advice. The FloodVerity check is a rain screening for one address, not a hydraulic study; it covers neither river and lake flooding nor sewer backup.