You may not have heard of runoff, but you've definitely seen it.
It's those curbside streams rushing into thirsty drains during a big rainstorm; the steady trickle down a soapy driveway as you wash your car.
Runoff is surface water that can't absorb into the ground before it reaches a waterway. In developed areas, more pavement means fewer opportunities for the water to soak in.
Runoff picks up all the oils, chemicals, dirt and pollution it finds on the road and other paved surfaces and washes them down the storm drain. Those contaminants flow into the nearest catch basin, which ultimately drains into nearby lakes and rivers.
This can pollute the water and upset the local ecosystem. The excess water can even contribute to flooding.
Sounds awful, right?
Thankfully, reducing your runoff is pretty simple. (Scroll over the numbers below for some ideas.)
If you've got a small space, reducing runoff is as easy as directing your downspout away from paved surfaces and into soakaway spots like gardens, stone beds or sandy soil, or buying a rain barrel to collect rainwater for use on your gardens and grass.
Or you might consider installing a rain garden. Don't be fooled by the fancy name! At our demonstration rain garden at Baxter Conservation Area, staff simply dug out a shallow space for the garden below the interpretive centre's downspout and made sure the soil was a nice mix of sand and compost for maximum soakability. They placed some loose mulch on top.
Staff then planted hearty native plants like blue flag iris, lance-leaved coreopsis, wild bergamot and purple coneflower – all flowers that don't mind getting their feet wet during a storm but which can withstand a little thirst in the dry spells, too.
As it rains, stormwater from the roof is directed into the garden, where it slowly soaks into the ground to be filtered out instead of running directly into the nearby Rideau River. Ta-da!
Rain gardens can be as modest or as massive as you choose, and inexpensive to get started.