A swale is a broad channel used for the movement and temporary storage of runoff. They can be made of concrete or formed with natural materials. Swales are the best way to move large amounts of water away from your home. Swales also can move a portion of the runoff into the ground and filter out runoff pollutants.
Drainage swales that are planted with native vegetation are commonly called bioswales. Swales can be effective alternatives to enclosed storm sewers and lined channels, where their only function is to rapidly move runoff from a developed site. On some sites, natural drainage courses may still be present and it is recommended that they be retained as part of the site drainage plan. Golf courses are probably the best example of the effective use of bioswales. In the design of golf courses, water management is key to controlling water conservation.
Many times swales can safely move water away from your foundation while conserving this same water for grass and other landscape plantings. Effectively moving water around a property can prevent foundation repairs while saving money on watering plants. In contrast to conventional curb-and-gutter concrete swales, bioswales can reduce both the rate and volume of storm water runoff around your home. Since this is achieved via absorption of runoff into the soil, swales in sandy soils will be much more effective than swales in clay soils. Swales are most effective in reducing runoff volumes for small storm events and on an annual basis can reduce storm runoff volumes by up to 15 percent in clay soils.
Drainage swales are applicable on virtually all residential sites. In suburban settings swales generally will be used in conjunction with foundation drainage. This effective combination can prevent water buildup around foundations which can cause foundation failures and water infiltration. While eliminating those areas in the yard that seemingly has constantly standing water or swampy areas, bioswales are the green way of conserving water. Take a look at your property today and devise a plan to protect your home while conserving natural water runoff.