Is collecting rainwater legal in BC, and can I drink it?

Question

Accepted Answer

Yes: rain collected off a roof needs no water licence in BC, and for one home no health permit either, though the Province's guidance says to treat it before you drink it. Using it to drink is where the rules start: a system serving more than one home needs the health authority's permits, and the Province's guidance treats rain as surface water that should be filtered and disinfected. Some island bylaws go the other way and require a cistern before a new home or suite. Look up the address or PID on PlaceDossier to see the record for that lot. No water licence: A water licence under the Water Sustainability Act isn't required to harvest rainwater (Ministry of Health guidance, s. 2). Water taken from a creek, lake or spring is another matter: see water licences. One home: A water system serving only one single-family home is exempt from the Province's rainwater treatment guidance, though the guidance says owners may use it to build a safe system (s. 2). The health authority reads a single-family residence as one house: a guest house, a suite or workers' cabins likely take the system outside it (its note 1). More than one home: The owner of a system serving more than one home is a water supplier under the Drinking Water Protection Act and needs construction and operating permits from the health authority before building it, and the water must be disinfected (Drinking Water Protection Regulation s. 5; guidance ss. 2, 4). Making it safe to drink: The guidance treats rain as surface water: it picks up bird and animal droppings, leaves and dust from the roof and the tank. For drinking water it recommends filtering and one form of disinfection, aiming at a 4-log reduction of viruses and of Giardia and Cryptosporidium, with a first flush diverter, screens and materials made for drinking water (ss. 4.1, 5.1). Enough water: Rain falls least when it's needed most. The guidance says a supply relying on rain alone can struggle to store enough for a dry summer, and that in many places rain is best kept for uses other than drinking or as a supplement to a well or a water system (s. 2). A report gives the yearly precipitation at the nearest weather station, and the wells near the lot. Renting it out: A landlord must not rent a home that isn't on a water supply system unless they can provide the tenant with drinkable water (Health Hazards Regulation s. 7, as the guidance quotes it). Bylaws that require a cistern: Some island bylaws require rain storage before a home is built. In the zones we've summarised: South Pender's Land Use Bylaw No. 114 asks a new house in its rural residential zones for an 18,000 L cistern (s. 3.14); Saturna's No. 119 asks the same of a new home, or an addition over 11.6 m², in the Eastpoint water management area (s. 2.17); Galiano's No. 127 asks it of a new home or cottage outside a water service area (s. 2.29); North Pender's No. 224 asks for an 18,000 L system before a secondary suite off a community water system (s. 3.10); Denman's No. 186 asks at least 1,000 gallons of storage for a second home by temporary use permit (s. 2.1). Other bylaws may have their own rule: ask the local government. The building code: The BC Building Code and local bylaws can add requirements for rainwater used inside a home, such as for flushing toilets; the guidance leaves those to them (s. 2).

Is collecting rainwater legal in BC, and can I drink it?

What the answer means

For one lot