Rainwater Harvesting Systems for Vancouver Island

Jamie Wallace/Owner


"Certified CANARM Professional"

CANARM Board of Directors


ARCSA AP.jpg canarm_logo_pack_digital_canarm_digital_xsmall.png



Rainwater Uses

Rainwater harvesting (RWH) is an important method of capturing water on Vancouver Island. The RDN Watershed Snapshot report from 2010 emphasized the need to promote rainwater harvesting with the region. Increase population, dropping groundwater levels, and a stressed ecosystem where reasons given. Rain water harvesting can play an important role in supplementing our water needs, especially in areas serviced by community water systems. Widespread use of RWH could delay or even reduce the investment in expanding or adding additional infrastructure.

Rainwater harvesting can assist communities which have community water systems that are stressed. Instead of expensive infra structure upgrades some communites may wish to consider RWH as an option. Since 80% of our rainfall ends up in streams and oceans, through run-off, RWH can dramatically reduce this. By collecting water during the rainy season, we are able to make better use of it during drier months.

Here are a few facts:

  1. Less than 3% of the water produced at a large municipal water treatment plant is used for drinking purposes; during the summer, about half of all treated (potable) water is sprayed onto lawns and gardens.
  2.  On average, 14% of municipal piped water is lost in pipeline leaks – up to 30% in some communities.
  3. A Canadian uses an average of 326 litres of water each day (in BC we use 490 litres) for household and gardening purposes (in contrast, a person living in Sub-Saharan Africa typically uses 10-20 litres each day)
  4. Water consumption usually drops 18-25% after a water meter is installed and drops 20-60% in household where a rainwater harvesting system is installed.
  5. Residential indoor water use in Canada is as follows: toilet – 30%; bathing and showering – 35%; laundry – 20%; drinking and cooking – 10%; cleaning – 5%


Three Categories of Rainwater Harvesting

Outdoor non-potable:

Non potable water for outdoor uses such as:

  • Landscape irrigation system
  • Swimming pool or hot tub filling
  • Water for livestock
  • Outdoor power washing
  • Vehicle washing
  • fire protection or emergency water


Indoor non-potable:

Non-potable indoor use is primarily used for flushing toilets. These systems are designed to send pressurized water to the toilets in your house. This is often in addition to outside use for the garden or vehicle washing. The average home with a low flow toilet will will save 120 litres per day. That adds up and takes a tremdous strain off any municipal or well water service.


Indoor potable:

Potable use of rainwater is used in locations were traditional sources of water are not avialbable. These systems traditionally use large stainless steel cisterns to capture as much rain as possible.