Contrary to popular belief, storm sewers do not carry storm water to wastewater treatment plants. Water that flows into storm drains or sewers ends up in the nearest water body. You can improve water quality by increasing the filtering capacity of your property. Once again the key is adding more woody vegetation to your property. A mixture of shrubs, trees and herbaceous plants more effectively filters out pollutants than grass alone.
Plants can reduce flooding downstream .
When flooding occurs upstream, plants on the streambank intercept the floodwaters, slowing them down and reducing the extent of flooding downstream. Plants are an important component of wildlife habitat. Habitat refers to the food, water, cover and nesting sites that all living creatures need to survive. Planting a diversity of native plants ensures that the needs of a variety of creatures will be met. Such plantings supplement the natural habitat.