Archive for June 12th, 2011

How Stormwater Drainage Systems Work

Proper stormwater drainage is important in many areas where there are frequent storms, a high risk of flooding, and coastal towns. The purpose of stormwater drainage is to remove excess water from rooftops, paved sidewalks, and streets. There are different methods that can be implemented in these areas in order to prevent flooding and control pollution that could go into the water supplies.

For paved walkways and streets, there are sewers and inlets that ease the process of stormwater drainage by allowing the water a place to escape. These inlets are usually placed on the curb of a street and prevent flooding. To keep these stormwater drainage systems from getting clogged, many drains come with grated coverings that catch large debris. This also prevents the debris from getting into the sewage system and causing additional problems later. For the smaller debris and particles that get through the grating in stormwater drainage systems, there is a catch basin directly underneath the grated covering. There are some catch basins that are designed to catch small debris as well as prevent noxious gases that come from the sewer from escaping.

Another important feature in stormwater drainage systems is the piping that comes in many different shapes and sizes. This piping also serves as a filter for certain types of debris depending on the shape on function. There is a staircase design in which water can pass through, but debris gets trapped on the different levels. Most stormwater drainage systems have some kind of an outlet that leads to a retention pond or similar structure for further treatment. These outlets also have grated coverings for the same purpose of catching excess debris that has gotten through the system.

Part of the risk that comes with stormwater drainage is the pollutants that may be picked up by rain water before entering the sewage systems. Rain water can pick up many things from residential lawns, rooftops, and roads, such as fertilizer chemicals, various metals, and motor oil. All of these can lead to low quality water being processed in the systems. Many cities have implemented filters that are designed to remove these chemicals from stormwater drains. This allows the water to be recycled for other uses or put back into natural waterways without damaging the environment. To learn more about how to keep your city’s water clean, there are plenty of informational websites hosted by the government to help people do their part in cleaning up the environment.