For urban dwellers, most of the water that lands on your property during wet weather will end up in creeks and rivers, via a series of artificial gutters, drains, and sewers. This run-off is known as stormwater, meaning that the rainfall is mixed with impurities. These impurities could be natural and mostly harmless – things like soil and leaves – but they could equally be plastics and other rubbish, fertilisers, oils, chemicals, and animal waste. The clogged drains and flooded streets that are so common after heavy rain are often a by-product of a drainage system that just can’t handle the water volume. This current status quo really doesn’t provide us with the best use of our rainfall, and also promotes contamination of rivers and harbours. Rain gardens are designed to drastically reduce the percentage of rainwater that becomes stormwater by keeping it within your property and having it naturally filtered by plants and soils.
They differ from rainwater tanks in that they can collect water from all parts of a house and land – roofs, driveways, patios, and lawns. Think of them as sponges that somewhat mitigate the impact of the dense city environments around us. At its most basic, a rain garden is comprised of several soil and sand layers of varying densities with plants and grass growing on the surface. The rain that falls on your roof can be channelled into this garden, where it is filtered through the soil. Some will evaporate and some will be used by the vegetation. You can set it up so that any filtered excess can be collected and used as you wish. It’s intended to mimic a natural ecosystem and, while one by itself might be just a raindrop in the ocean, the cumulative effect of many can be astonishing. They’re not intended specifically to store water; rather, they encourage natural filtration and minimise the amount of impure water that flows to where it simply isn’t needed.
While regional and federal initiatives to encourage networks of rain gardens are currently few, with the right planning and cooperation, this vital resource could make towns and cities considerably more economical. For one thing, it makes properties a little more self-sufficient and less reliant on supplied water, much like having tanks set up.
If you’re a tenant, or live in an apartment, your options for creating a rain garden are unfortunately limited, but homeowners will find plenty of options available; check online to see what could suit your home. Even those without much of a green thumb can create their own, and those who have installed backyard rain gardens report that most rain events result in no water leaving their property – it’s all retained to be used by plants, grasses, and soil, or collected in tanks. That’s good for the environment, good for easing your water bills, and good for your conscience too.