Why we’re investing in Rainwater Harvesting: Part 1

The drought and wildfires of 2018 really drove it home for us: We were watering our gardens with propane

This was directly opposed to our dream a decade earlier. That’s when we sold our gracious century-old home in Regina and bought a 5-acre parcel of land in West Kootenay. Our plan: To develop a solar-powered permaculture homestead, leaving the land more abundantly productive and resilient for the generations to follow us. 

Today, we live off-grid in a straw bale house that is powered by solar energy with backup propane. Our extensive gardens produce much of our food; we raise egg-laying hens, and chickens and rabbits for meat. A variety of nut and fruit trees and berry bushes comprise our growing food forest. And they all need water—lots of it—delivered mostly from our well, about 140 feet underground. 

When we embarked on our project a decade ago, we had expected to have a solar energy surplus in mid-Summer. We were so wrong. 

That’s mostly because our power draw spikes for several minutes every time our well pump is triggered by a drop in the water level of our pressure tank. Turn on a drip hose for 45 minutes, and this may happen several times. Water just one of the gardens, and the state of charge (SOC) in our solar battery bank will plummet. Even in years where rainfall approaches 30-year historic averages, we may need to use propane on the sunniest days.

But the parching drought and devastating wildfire seasons of 2017 and 2018 made the problem much, much worse. Smoky skies meant less solar gain—we noted reductions of up to 40% on many days—and extended lack of rain forced a massive surge in well water use from June through August. We drew down our propane pig at a rate exceeding that of the short, dark days of December. 

We have come to view ourselves as living on the front line of exigent climate change. We take nothing for granted. We can no longer count on historic weather patterns that shaped 20th century agrarian practice. We can no longer assume an infinite, stable groundwater supply. 

For us, the time has come to see how rainwater harvesting can help. 

In mid-May, 2020, we undertook a pilot project at our chicken coop and rabbitry. For a modest $800 in materials and a few days’ work, the chicken coop system was collecting roof rainwater by May 30. The rabbitry system followed a week later. These low-tech rainwater harvesting systems will likely generate more than 2,000 litres of water, as we draw from the tanks periodically to use on the farm, and later rains top up the levels. 

With generous rainfall since late May, we haven’t had to draw from the tanks very often, however, we have used about 400 litres in the food forest berry and nut trees.  As of July 10, this volume has been fully replenished, and our pilot system is ready to go with 2,000 litres when we need it most in dry midsummer weeks to come.  

Our pilot project fits the narrowest definition of rainfall harvesting, the capture of roof rainfall in a container. We also use garden straw mulching extensively. Engineered earthworks—such as raingardens, ponds, and swales that help channel water across the land—are known as passive rainwater harvesting. While more complex and expensive, their use further amplifies the benefits. 

But the promise of rainwater harvesting goes well beyond its obvious value to individual homesteads. When enough households harvest rainfall, we can make a quietly vital contribution to community resource stewardship and ecosystem resilience. 

As our population increases, particularly in cities, our aging water infrastructure faces intensifying demand pressure. When these systems fail, or when natural disaster strikes, entire cities or neighbourhoods may lose access to water, sometimes for weeks. In contrast, when a homestead rainwater harvesting system fails, usually only one household is affected. 

We can learn from the experience of the world’s driest country. Over one in four houses in Australia operate a rainwater harvesting tank, and at least two million Australians rely entirely on rainwater harvesting for all their needs, including safe drinking water. By 2015, the Australian Bureau of Statistics reported that rainwater harvesting systems produced 9% of residential water in the country, valued at about $500 million.

Just imagine the possibilities for Canadians! When more households incorporate rainwater harvesting as part of our water and energy management, we begin to shoulder more responsibility for our own water consumption, while conserving groundwater aquifers for our grandchildren. 

Finally, rainwater harvesting can advance a cleaner, greener, more resilient way of life, offering yet another renewable-based adaptation to climate change—in support of the objectives of West Kootenay EcoSociety’s 100% Renewable Kootenays campaign. 

Learn more in Part 2: Our first 2,000 Litres of Rain—Captured! 

Anne Mowat is an EcoSociety member and a volunteer with the 100% Renewable Kootenays campaign. She lives off-grid in a solar-powered straw bale house in Glade with her spouse, Susan Risk, their English Shepherd, Charlotte, and cat, Solly. Over the past decade, they have been gradually developing a permaculture homestead, and now grow much of their own food, including produce, eggs, and meat. A veteran PR professional, with degrees in business (Queen’s) and journalism (Ryerson), Anne still consults part-time from her home office.