Rain Gardens are bowl-shaped gardens designed to absorb stormwater runoff from impervious services such as roofs and parking lots. They range from small formal home gardens to large commercial bioretention gardens.
In natural ecosystems, rain largely stayed where it fell, filtering through soils, roots, and plants. Most of the water that entered our surface waters was pristine groundwater. On the other hand, stormwater is a byproduct of land development, a man-made phenomenon. If left unchecked, it carries up to 70% of the pollutants that enter our waterways. It is a major contributor to non-point source (NPS) pollution. Keeping rain where it falls is an important part of protecting our rivers and streams from unwanted chemicals and silt, and rain gardens provide an effective, attractive remedy.
Rain gardens have a ponding area, though they are not ponds. They are planted with perennial plants and may have grasses, trees and shrubs. Stormwater is routed to the ponding area where it is absorbed and filtered. Many of the plants used are native to the region and have extensive, deep roots. To increase its effectiveness, the garden bed is prepared or replaced to a depth of two feet in order to de-compact the soils and increase the rate of absorption.
Benefits of Rain Gardens
- Rain gardens are attractive landscaping features.
- Rain garden plants create wildlife habitat.
- Rain gardens don't need to be fertilized or sprayed, only weeded and mulched. They reduce the amount of lawn you have to maintain.
- A rain garden on your property makes you part of a solution to stormwater pollution. Even small rain gardens absorb a lot of rain.
- A rain garden can be part of a stormwater reduction plan to help solve problems of combined sewer overflows (CSOs).
- Rain gardens can remove many common pollutants.
- Rain gardens are low maintenance. Once established, they require no fertilizer, watering, or mowing. A once a year cleanup, addition of shredded hardwood mulch to keep the surface moist and tidy, and removal of weeds and invasive species are all that are required.
- Rain gardens can contribute to groundwater recharge, a natural process that is interrupted by soil compaction and hard surfaces created during development and building.
- A rain garden project can educate the public about the problems that stormwater runoff creates, while providing an attractive solution.
Since ancient times, people have collected rainwater for use during dry periods. Today with rising utility prices and the growing need for proper stormwater management, rain barrels are more attractive than ever.
Rainwater is naturally soft, and can be used as-is for a number of different uses, including gardening and washing. If you want to use rainwater for drinking, you need to be sure it is properly filtered and meets the legal requirements of your community for potable water.
For every inch of rain that falls on a catchment area of 1,000 square feet, you can expect to collect approximately 600 gallons of rainwater. Ten inches of rain falling on a 1,000 square foot catchment area will generate about 6,000 gallons of rainwater. For more information on how to calculate the catchment area of your building and the average rainfall in your area, see the Rain Barrel Guide at http://rainbarrelguide.com.
The photo shows one of the rain barrels in use at the Inventory Management building at the Ellington Center.
As human population grows, so does the demand for agricultural food and fiber. An integral part of protecting and enhancing the environment is identifying ways to use land without abusing it. The most effective and practical methods are referred to as Best Management Practices (BMPs). Not only can agriculture and conservation co-exist practically, conservation has become an indispensable step in securing a steady, safe and affordable supply of agricultural products for everyone into the foreseeable future.
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