Options for controlling storm water drainage include installing drain tile systems, culverts and french drains or creating swales and rain gardens. Another option that eliminates runoff and lets water gradually sink into the soil is to use permeable concrete or asphalt for walkways, patios and driveways, or leave small spaces filled with sand or gravel when using concrete pavers. Connecting downspouts to a drainage system and adding a channel drain in a driveway are other options for redirecting excess water.
Perforated poly drain tiles allow the surrounding soil to reabsorb excess water. Culverts in residential applications channel water under a driveway or along an entry road. French drains are trenches filled with gravel. A perforated pipe in the center is pitched so that water flows in and out of it, and the soil reabsorbs the water through the gravel.
Swales and rain gardens are both storm drainage options and landscaping features. A swale is a natural or man-made depression that follows the contour of a slope to safely carry excess water to a drainage system. Plants and grass in the swale and on its banks actually absorb much of the water. Rain gardens are shallow basins planted with flowers, often at the base of a steep slope, and designed to catch storm waters that then soak into the ground.