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Watershed Wise: Residential Rain Garden

Watershed Wise-resident

How to Build a Rain Garden

A rain garden can help beautify your yard and help protect the environment. Think of the garden as a shallow bowl, about 6 to 9 inches deep, that captures rainwater from your roof, sidewalks and driveway. The rain garden allows you to slow down the flow of stormwater entering our waterways, to soak up some pollutants and filter the runoff that would otherwise end up in a  storm drain, and ultimately in our creeks and rivers.

The garden might be most ideal in your front or backyard depending on the amount of sunlight. Full sun is best. Make sure your rain garden will be at least 10 feet from your home, backyard fence, or any other building. Avoid underground utility lines, a septic system, or tree roots you don’t want to damage when digging. Before you start digging your garden, you will want to do what’s called a percolation (“perc”) test to see how quickly water soaks into your soil.

Rain gardens may be used in the Edwards Aquifer Contributing Zone to treat stormwater for increased quality and to reduce flows off the property.  However, rain gardens must either be lined with an impermeable liner or be part of a treatment train of BMPs if installed over the Recharge Zone.

What contaminants will the garden filter out of my yard?
So how do I get started?

Perc Test

Why a perc test?
How do I do a perc test?
What if the soil drains slowly? Should I avoid a rain garden in my yard?

Rain Garden Blueprint

How do I determine the size of my rain garden?
What if my yard is on a steep slope?

Digging and Planting

How do I minimize erosion or soil loss?
Now can I start digging?
How do I decide what plants to put in the rain garden?
Will my rain garden require a lot of maintenance?