Green Infrastructure for Your Yard

With increasing pressure to better handle flood events and improve water quality, many municipalities (including the City of Austin) are implementing measures to slow down, retain, and treat stormwater on-site, allowing it to permeate into the groundwater while carrying less runoff pollution. The methods for accomplishing this are collectively known as green infrastructure. While cities are funding these projects with public money and installing them mainly on public land, many are also rolling out programs that encourage private property owners to create similar mechanisms in their own yards or campuses.

Residential green infrastructure can take many forms. One of the most popular and well known are rain gardens. These are essentially shallow, basin-like depressions strategically placed to receive and hold runoff for a short period of time while plants “scrub” the water of pollutants. The plant root systems help water infiltrate into the soil and eventually the underground water table.  Drawdown only lasts a few hours to a couple of days. This prevents persistent standing water and avoids mosquito problems.  Another mechanism is bioswales, in which water travels along a shallow channel at a slow rate, utilizing plants and plant roots growing in the channel to buffer the water before it enters established waterways such as tributaries, creeks, and rivers. A third mechanism is a vegetated filter strip, which is a simple span of deep-rooted plants (usually native climax grasses) that run the width of a runoff area to slow down stormwater and help bring it underground before it reaches a waterway further downhill. Other green infrastructure mechanisms include terracing, rain barrels, downspout rerouting, and permeable pavers.

For more information on residential rain gardens give ESC a call!  For information on the City of Austin rain garden rebate program, click here.