Rainwater Harvesting on Vancouver Island
Rain…what is rain? Rain is defined as: “Rain is liquid water in the form of droplets that have condensed from atmospheric water vapor and then precipitated—that is, become heavy enough to fall under gravity. Rain is a major component of the water cycle and is responsible for depositing most of the fresh water on the Earth.” 
We live on Canada’s west coast and more and more we are hearing people talking about saving rainwater. This leds some people to say “You have got to be kidding?” We receive a large amount of rain, particularly during the winter, which means we must have more than enough ground water for our needs… we open the tap and water comes out, so why the concern?
Vancouver islands population has been steadily growing for the past few decades as other Canadians discover Vancouver Island. The RDN contains seven watersheds which supply all of our regions water needs. Of those seven all of these appear to be under some level of stress. Here are a few notations found with the RDN Watershed Snapshot Report 2010. 
• Groundwater levels seem stable now, but there are questions about sustainable yield.
• Significant number of concerns regarding dropping groundwater elevations in Qualicum River Village area and Spider Lake.
• Dropping groundwater levels, stressed bedrock aquifers, such as the Benson Meadows area (Aquifer 211), Superior Road/Westwind Drive (Aquifer 213)
• Water supply issues in Lantzville (as many people are becoming aware)
So it seems that water conservation for everyone living within the RDN is not only a good idea but one that is also necessary. One very effective way to supplement our water needs is by employing Rainwater harvesting, also known as RWH. Humans began saving rainwater over 5000 years ago in what is now Iran.
What is Rainwater Harvesting?
Rainwater harvesting is an ancient method of collecting rainwater and storing it for later use. Traditionally, this involves harvesting rain from a roof, although in Asia it is common to harvest surface water. The rain is collected into some form of roof gutters which are then directed into a network of piping and eventually ends in a cistern or other storage devices.
Many areas of the world actively harvest rain out of necessity, we are fortunate to be in a position where we can be pro-active and begin using these techniques before our situation worsens.
Rainwater harvesting is a viable approach that could easily be employed within communities like Lantzville. All that one needs to do in order to take advantage of this resource is to capture the free water falling on your roof and direct it to a rainwater storage tank. With this approach, we can have better control of our water supply and replace all or at least a substantial portion of your water needs. Rainwater harvesting systems can be configured to supply your whole house and/or your landscape needs.
What are the benefits of rainwater collection?
• Rainwater is a sustainable source of water… we get an average of 1200 mm or 1.2 meters of rain per year. This translates into around 230,000 litres of water coming off the average roof.
• You have more control over your water supply…water sovereignty.
• It promotes self-sufficiency and helps conserve existing water supplies.
• Rainwater is better for landscape plants and gardens because it is not chlorinated.
• It reduces storm water runoff from homes and businesses, reduces wear and tear on taxpayer funded infrastructure (ditches and storm pipe).
• It can solve the drainage problems on your property while providing you with free water.
• It uses a simple approach that is affordable and easy to maintain.
• It can be used as the supplementary source of water or as a back up source to wells and municipal water.
• The system can be easily retrofitted to an existing structure whether commercial or residential.
• Rainwater harvesting systems are very flexible nature and can be modular, allowing expansion, reconfiguration, and even relocation, if necessary.
• It can provide an excellent back-up source of water for the use in emergencies.
There are basically three areas where rainwater can be used:
• Irrigation use
• Indoor, non-potable use
• Whole house, potable use
What are the uses of collected rainwater?
You can essentially use rainwater anywhere you use tap water. The idea of using drinking water to flush our toilets and water our lawns is wasteful and fundamentally irresponsible, especially in light of population growth and water shortages across Canada.
Rainwater collection is a technique that can be used to green your home and to lessen your environmental footprint.
Next issue we will dive into a bit more detail surrounding RWH and how it is being used on Vancouver Island.
Rainwater harvesting system at the Nanoose Bay Firehall