Controlling runoff at home can be easy

Last week, I was able to attend a two-day workshop on stormwater practices geared towards teaching the best ways to inspect and maintain green stormwater infrastructure.

No doubt, the workshop is tailored to a niche community which I happily take interest in but understand that many others do not. This meant getting deep into the weeds about various runoff management devices and techniques that help us alleviate the problems with uncontrolled runoff while also examining the nuances between different installations. Throughout this workshop, three simple points were reiterated as the foundational consideration whenever we implement a practice: rate, quantity and quality.

Storm runoff has three influencing factors: the rate at which it flows, the quantity of water and water quality. If you’re hung up on the difference between rate and quantity, imagine the difference in trying to empty a bathtub of water through a straw and fire hose. You’ll move the same amount of water far slower through the straw than the firehose. We want that. In fact, our goal in tackling rate, quantity, and quality is to create spaces that collect, reduce, and improve the incoming water.

Following this sequence, collection is the first stage in the process. We collect it so we can do something else with it and ultimately keep it from going down the storm drain.

Next is reduction, which is achieved by providing time for infiltration, evaporation or uptake by vegetation. Simultaneously, we have improvement as pollutants are reduced by filtering, settling, plant uptake and chemical breakdown when stored in the structure.

We can see all this in action by observing a structure like a rain garden during a rain event. Water will be directed into the depressed area and hopefully collect a one-inch rain event from whatever source its meant to handle (maybe a roof or driveway). When stored, it will start infiltrating into the soil and being wicked up by plants or porous debris like mulch. Cleaning is had by filtering from the soil, settling of debris suspended in the water, and uptake of otherwise polluting nutrients by vegetation. When all is said and done, entering runoff may never leave the garden or it may spill over the edge but at a slowed rate and cleaner than it would have been otherwise.

All this is achieved by simply creating a properly sized depression in the ground with some functional and pretty plants. Similar effects can be seen if you reroute a drain spout into your grass or if you install a rain barrel. Planting a tree in your yard also dramatically reduces runoff and greatly improves infiltration rates.

Managing stormwater on your property doesn’t have to be complex and might be achieved from some simple renovations. Feel free to reach out to our office or me to learn more.

Chris Gass is a Minnesota GreenCorps member with the Carlton Soil and Water Conservation District whose columns will focus on environmental topics and stewardship, particularly in cities and towns.