Surface drainage

Surface drainage

Surface drainage system - a complex engineering net organized for the collection and drainage of storm-water and melt snow from a large area. Efficient storm-water drainage has to cope with its functions during the spring thaw, fall incessant rains and summer abundant rains. Most of drainage systems are supplemented by underground drainage, although on the elevated areas it is not needed.

The principle of operation of the surface drainage is quite simple – storm- water or snowmelt collected in the sewage channels, which are connected to a single extensive net and converge at the lowest point of land at the entrance to the collector, pond or roadside ditch. To protect drainage systems from the trash accumulation, fallen leaves, branches and other drain gratings are used. Gratins cover the channels. But in addition to practical functions such gratings perform aesthetic function, hiding under the channel system.

If surface drainage is arranged in the areas, where fall of different contaminants into channels are possible: sand, small stones or gasoline (petrol stations, service stations, highways, parking lots), so the surface drainage comlete with sand traps and accessories for wastewater treatment. Any drainage system is designed as a comprehensive system, because of the quality of its arrangement depends on the organization and drainage of storm-water. Therefore, while design and use of the surface drainage it’s necessary to take into account many factors:

• rainfall intensity in the area
• runoff area
• area relief
• duration of the passage of the collected water on the surface and channels to the design section
• other circumstances

Type of surface drainage

There are two types of surface drainage: point and linear. Currently, linear and point drainage systems are used in the storm-water drainage and supplement each other in their functional purpose. Linear drainage consist ofchannels that are fitted under a bias and converge at the lowest point when leaving the collector. If the system of gutters arranged correctly, the surface water quickly and organized collected and removed outside the area, thus ensuring safety of the road surfacing and foundations, pavement and plants. To protect drainage sytems from leaves and trash protective gratings are used that also sfulfill decorative function and ensure the safety of pedestrians and vehicles.

Elements of drainage system: sand traps, storm water inlets, wells and other. Each performs certain functions. Sand traps are designed for purification of sand, silt and small stones. Storm water inlets are fitted in the gutter and perform quick task stormwater receiving fluid flowing from the roof of the building. Often rainy sewerage includes auditing (surveillance) well to provide access to private networks, sewage networks, and in this case serves Sands. On top point elements of drainage systems are covered with removable grates that serve both decorative and protective functions.