Does a BC house need a backwater valve, and who pays when the sewer backs up?

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Under the 2024 plumbing code a drain below the street that sewage could back up into needs a backwater valve; the pipe on the lot is the owner's, not the council's. Sewer backup is sewage pushed back up a house's own drain when the main is full or blocked; it comes out at the lowest drain, often a basement floor drain or toilet. A backwater valve is a flap in the drain that closes when the flow turns back. For a buyer the questions are whether the house has one, whether it's kept clean, and whether the policy covers sewer backup. Look up the address or PID on PlaceDossier to see the record for that lot. The rule for new work: The BC Plumbing Code 2024 is the National Plumbing Code 2020 as BC adopts it, for building permits applied for on or after March 8, 2024. Where a building drain or a branch may be subject to backflow, a fixture below the level of the adjoining street is protected by a backwater valve; gate valves and screw caps, which need someone to close them, no longer count (Division B, Subsection 2.4.6; the Province's bulletin P24-01). Before March 2024: Under the 2018 code a gate valve or a backwater valve went on each fixture drain below the street, or on the branch where several fixtures on one storey shared it, and a floor drain could take a removable screw cap instead (BC Building Code 2018, Article 2.4.6.4, as the District of Saanich's bulletin quotes it). A house is built to the code of its day, so an older one may have no valve at all and isn't made to add one (our reading). One valve, one home: A backwater valve in the building drain itself must be a normally open design and may serve only one dwelling unit (Article 2.4.6.4 (2), as Saanich's bulletin quotes it). A suite is a dwelling unit of its own, so a house with a suite may need its valve moved or another added: the City of Calgary's 2022 advisory says so of the same national code. Whose pipe it is: The City of Coquitlam puts the pipes on the owner's side of the property line on the owner, and the District of Peachland installs an inspection chamber just outside the line for cleaning the service connection on its own land. Councils set the line in their sewer bylaws, so ask yours where the owner's part ends. What may drain to the sewer: Councils keep rain out of the sanitary sewer: Peachland allows no roof or storm drainage of any kind into it (its sewer connection bulletin). Under the 2018 code a subsoil drain feeding a sanitary sewer that can surcharge had to be connected so sewage can't back up into it (Article 2.4.6.4 (6)). A foundation drain or sump pump tied into the sanitary sewer is worth raising with the inspector (our reading). Suing the council: A municipality, regional district or improvement district isn't liable in nuisance for damage arising from the breakdown or malfunction of its sewer, water or drainage system (Local Government Act s. 744), so a claim has to show the council was negligent, as Coquitlam's page says. Notice in writing of the time, place and manner of the damage must reach the council within 2 months (s. 736). Insurance and disaster aid: Sewer backup is optional coverage on a home policy, and the Province's Disaster Financial Assistance doesn't pay for sewer or sump backup, as damage that could have been insured (see flood insurance). Ask the insurer whether it covers this house for sewer backup, whether a backwater valve changes its terms, and what it needs to know about past backups. What it means for a buyer: Ask whether the house has a valve, where its access lid is and when it was last cleaned, and whether the basement has ever flooded from a drain; have the inspector find the valve and look at the floor drains, the cleanout and any sump. A valve the inspector can't find or open is a question for a plumber before subjects come off (our reading).

Does a BC house need a backwater valve, and who pays when the sewer backs up?

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