Working To Stop Storm Water Run-Off
 On A Hilly Lot

Barbara Mrgich
Adams County Master Gardener

(12/8) Is your garden located on a slope? When we have a heavy rainstorm, does the water seep into the soil, or does it run down the slope and flood the area at the bottom of the hill?

There have been many cases of neighbors who actually got into law suits because the water from one lot ran into the neighboring lot and caused flooding. There is an easier fix to this problem than you may realize. ROCKS can help a lot!

Our entire lot is part of a larger hill that slopes from back to front. The soil, at the time of purchase, 30+ years ago, was rock hard. We planted a couple trees, which nearly died because they never got enough water to their roots. I finally realized that rain would hit that hard soil and run right down the hill. Each spring, I had to shovel the soil off the sidewalk at the bottom of the hill that had washed off my garden during the winter. I knew that somehow I had to slow it down if I wanted my trees to live.

We had a small patio built which became the only level spot in the backyard. In the construction of the patio, the men dug down about six inches to make a stable base. I was totally amazed at how much soil and large rocks come out a six inch excavation! Of course, they were prepared to haul everything away, but I wouldn’t let them take the rocks. I took those rocks and serpentined them through the area just below where my trees were dying. I just strung them together tightly enough to prevent water from gushing between them, and, with a little soil backfilled behind them, this was enough to do the trick. For added assurance, a little further down the slope, I repeated this line of rock again. Over the years, the garden plants and shrubs have grown up around them and, by now, the rocks are barely noticeable. The result is that now I have a healthy garden and no more puddles and eroded soil on the sidewalk following a rain.

At the front of our property, down along the street, the slope dropped off sharply enough to make mowing dangerous. I found directions in a magazine (no internet then), and built a retaining wall. It started out with just a few scattered plants and shrubs. Twenty years later, it was quite full of plants and shrubs whose roots work to absorb and filter rainwater run-off.

Of course, it is not officially a rain garden. Rain gardens are depressions in the soil, this is not. However, I contend that it does the same work as a rain garden. Water runs off our roof and also comes down the slope that starts a long way up above our property. Instead of running across the street, it runs into my garden, and seeps into the soil. Isn’t that the work of a rain garden?

The point of this article is to say that it is not impossible for a homeowner to make a big impact on your own property with DIY projects. By retaining storm water on your own property, you are not only being a good neighbor, you are doing your part to protect the aquatic life in our streams, rivers, lakes and the Chesapeake Bay. Excess fertilizer, animal droppings, spilled gasoline and other pollutants that wash off our roof and lawns flow unfiltered into waterways to kill the fish, shrimp, crabs, etc. that we take for granted on our dinner tables. By filtering that water through the soil, it is cleansed of toxins, and stops the destruction.

These are other ways to help put an end to the huge problem of storm water run-off. Native plants in general have deeper roots to help sop up extra water. Planting the right native plants in a problem spot will go a long way to reducing excess water. The planting of riparian buffers and installation of rain barrels are two more steps that homeowners can take. Let’s all work to do our part. If you are interested in tackling a project such as this on your own property, this is the perfect time of year to do it before the garden starts to grow again.

Read other articles on ecological gardening & native plants

Read other articles by Barbara Mrgich