Stormwater is liquid that results from rain, snow and other forms of precipitation. In an urban environment, we typically use the term “stormwater” in the context of surface water that aggregates on impermeable surfaces.
It just sounds kind of scary, right?
I mean, you’ve heard the term. You know it’s a problem. You understand that addressing it is of critical importance.
But unless you work in landscaping or an environmental niche, you may not understand what to do about it. As a homeowner, building manager, investor or institution, you probably feel unsure what your responsibility to the environment should take – and that’s okay.
Let’s talk about the definition of stormwater and what it means for you today.
What Is Stormwater?
There exists a misconception that stormwater is only the yucky stuff that makes it down to street level and rushes along the gutters or pours into the sewer system, but that’s not the case.
Nor does stormwater have to come from an actual storm (defined by Merriam-Webster as “a disturbance of the atmosphere marked by wind and usually by rain, snow, hail, sleet, or thunder and lightning” or “a heavy fall of rain, snow, or hail”).
Rather, stormwater is any precipitation that falls from the sky. A light snowfall, a gentle spring drizzle, dumping hail, a summer thunderstorm that drops an inch of water at a time.
That’s stormwater. Now the question is … where does it go?
What’s Wrong with the Urban Stormwater Cycle?
The difference between stormwater in cities and in nature is significant, as demonstrated by this image showing natural, urban and sustainable water cycles.
In rural and wilderness areas, stormwater trickles into the ground, penetrating soil and eventually filtering down to the water table.
In metropolitan areas, water can’t get through soil due to cement, concrete, asphalt and other impermeable surfaces. It runs over those surfaces instead, rarely retained or detained due to lack of urban stormwater management plans.
That’s bad news for several reasons. For one thing, there are lots of pollutants lying around on city surfaces. When water rushes over them, it picks them up.
Then it heads to combined sewers, systems built in previous centuries that combine sewer contents and graywater from our homes with stormwater from city surfaces. When it can’t handle the load, it backs up into streets, bringing disease and parasites from our toilets into our walkways and outdoor living spaces. That’s a combined sewer overflow event, and it happens all the time.
Even when it doesn’t back up sewers, stormwater carries those pollutants and diseases through sewers and across streets into natural waterways, where it harms or kills wildlife.
A Better Stormwater Cycle
Now that you understand a bit more about what stormwater is and does, it’s time to make a plan that helps address it.
A sustainable urban water cycle creates more permeable areas for stormwater to go such as green roofs or rain gardens.
These help retain (hold onto permanently) and detain (slow down) stormwater. Water that does run off gets funneled through natural treatment spaces, such as wetlands, which can help absorb and break down nutrients and disease.
It’s a hefty task, to be sure, but with help you can create your own urban or suburban stormwater management plan to help do your part.
Let Ecogardens be a part of your solution.