The latest buzz-word in gardening is “rain gardens.” But what is it? Rain gardens are basically a depression in the earth intended to capture rainwater long enough for it to have the chance to soak into the soil rather than run off into the nearest sewer drain. Complete with plants that like their feet wet from time to time, rain gardens are not only functional but they are also nice to look at. To understand why this is important, we need to talk a little about the ocean and, of course, the rain.
Where Does the Rain Go?
When it rains, did you ever wonder where the rainwater goes? Sure, some of it soaks into your garden and lawn and some of it evaporates. But surprisingly, the majority of it ends up in the ocean. I know this may sound strange – especially if you live right smack in the middle of North America, miles and miles from the nearest ocean, like I do. But even from there, some rainwater will flow all the way to the coast. This generally happens during heavy rain when the water is falling faster than it can soak into the soil, or in urban jungles where there isn’t soil for the rain to soak into. Instead, it flows into a sewer or retention basin, which eventually leads to a stream or river which flows … you guessed it … to the ocean.
During this journey, the water picks up pollutants – many of which come from pesticides and chemicals applied to our lawns – carrying them to the ocean. You may have heard or read about fish kills and dead zones in the ocean with one of the largest floating off shore in the Gulf of Mexico. The Mississippi River discharges enormous volumes of water loaded with suspended solids, excess nutrients, and pesticides. This concoction of pollutants means the water is devoid of life.
There are a couple of things you can do to keep this from getting worse. The first is to cut back on or stop the use of lawn fertilizers and pesticides. If we don’t use them, they can’t get into our waterways. Next is where rain gardens come in. A rain garden helps keep the water that falls on your property, on your property and out of the ocean.
Let’s take a look at the amount of water that can be generated on your property. Typical amounts generated from average homes would start at 2,200 gallons in a 1-inch rain event. This does not include the water that runs off of your lawn. This is just what falls from your roof or runs off your driveway, walkways, and patios and other impervious surfaces.
The Garden of Rain
The best way to keep the rain water on your property is to route the water that flows from your roof and downspouts to a useful place. Dig out an area near the exit point and downhill from the downspout so it’s several inches lower than the surrounding ground and work the soil to allow for water absorption (water will not soak into compacted soil). Then dig a trench from the end of the downspout to the depression and install drainage piping from the down spout to the depression to supply it with enough water to create the desired effect. Remember, a larger roof will require a larger rain garden to properly handle the incoming water. There will also be times when your rain garden overflows during severe rain events.
Place a series of stones in front of the pipe opening to slow down the force of the water. Soil amendments may be necessary depending upon the condition of the existing soil or the requirements of the plants. The rain garden can be planted with a variety of water loving plants to fit any garden style. These small damp areas are not only important for a diverse mix of plants, but they’ll attract a variety of animal life that relies on these wet areas for survival.
If the water in a rain garden stays pooled up long enough, it will evaporate through a process known as evaporative transpiration. This occurs when plants absorb the water during their growth process and transpire the water vapor out of their leaves as a byproduct of photosynthesis.
Practical and Beautiful
This concept is easy to do and can be added anyplace where water management is needed, even if it’s just a low spot in your yard that naturally collects water. I have also added one to my pond overflow area to capture any excess water.
As you can tell, the health of our waterways is essential to the world around us, and with a little planning we can all do our part in promoting a cleaner water initiative. A rain garden serves both a practical purpose, but it is also beautiful. So, no matter what the water quality challenge we all can have our little piece of conservation and enjoy the benefits that come as a result.
For more information on rain gardens, rain barrels or how you can help conserve water, visit Aquascapeinc.com.
