Rain gardens are no cost features that can be incorporated into your yard, providing your community relief from storm water flooding while adding an opportunity to develop an interesting ecosystem in your garden. The rain garden we’ve incorporated into the backyard of Equinox House will temporarily hold up to 2000 gallons of storm water, in addition to the nearly 1700 gallons of water held by our rainwater harvesting cistern. Over a period of three to four days after large rain events, the water in the rain garden seeps into the ground and through the surrounding berm, returning the rain garden back to usable yard space.
How do you design a rain garden? Your local climate’s precipitation characteristics, building size, and yard space all factor into the design of the rain garden. We’ve begun establishing plants that enjoy being on the edge of streams and lakes, such as river oats and cardinal flower, around our rain garden. A low spot in the berm controls where overflow from the rain garden is channeled for extreme rainfall events. The result is that we have capacity to retain the water from storms producing up to 4 inches of rainfall, and minimizing rainwater runoff for those rare events exceeding these levels of rainfall.
Our Sketchup model shows details of the rain garden in the backyard of Equinox House. As in the other aspects of Equinox House, the rain garden is a simple feature that is based on results from a detailed computer prediction model developed by Newell Instruments (learn about some of our design services here) that simulates the operation of the house water consumption, roof area, cistern volume and detailed meteorological data for central Illinois.
