Why Rain Gardens?

Why Rain Gardens?

Our creeks needs your help! Rainwater is running off roofs, roads, driveways, lawns and packed soils, and flowing too quickly into the creek! These urban surfaces have dramatically reduced the ability of rain water to sink into the ground and regenerate  ground water supplies. Instead, rain is bringing a large, fast burst of water to the creek which is scouring banks and degrading animal habitat. This runoff also often carries sediment and fertilizers, leading to water quality problems with our drinking water supply reservoir.  You may not have a creek in your yard, but the rainwater that flows off your yard continues on, perhaps into the street or storm sewer, and ends up in a creek near you.  That creek feeds a larger one, which flows into a drinking water supply reservoir.

Building a rain garden is one way you can help promote healthy creeks which sustain invertebrates, fish, frogs, birds and mammals – the entire chain of life.  A rain garden filters rain water and allows it to slowly sink into the ground.  It is created in a low spot in the landscape, and is  intentionally designed to capture rainwater and to become an attractive feature to your yard.  See students at McDougle Middle School plant a rain garden here. The Town of Chapel Hill Stormwater Management Division produced this excellent brochure describing how to build one. Click on brochure pages to enlarge type.

How to size your rain garden

Alternatives to rain gardens. A rain garden is not the only way to create a more creek friendly yard. Any lawn area can be converted to a garden or natural area with positive results. If you have a stream on your property, it is important to protect, or create, a buffer with woody vegetation and nonchannelized runoff entering the buffer to allow the buffer to serve as a filter for the runoff.  Check local ordinances and rules for buffer requirements. See Chapel Hill Ordinance and Carrboro Ordinance.

• The size of a lawn could be reduced by planting woody vegetation which increases the rate of rain water that is absorbed by root systems. Trees and shrubs have the added benefit of catching rainfall in their leaves, stems, and canopies, thereby calming the rate of the rainfall flowing downhill to our creeks.
• Native grasses are superior to turf grass because of their much deeper root systems and less need for fertilizer, herbicides and watering.  Trees and shrubs have the added benefit of catching rainfall in their leaves, stems, and canopies, thereby calming the rate of the rainfall flowing downhill to our creeks.
• Redirecting rainwater from a roof downspout to an area of your yard where it can be absorbed is recommended.  Avoid piping rain water directly onto drives and streets and into storm drains that lead directly into our creeks.

NC Clean Water Education Partnership offers tips here.