Process to treat rainwater runoff from roofs, roads or car parks

摘要

Process and assembly for treating rainwater runoff is claimed especially from building roofs, roads etc. The first water to drain from the surface flows to an assembly which separates the initial inflow and retains it in a tank (6). The volume of water separated and retained depends upon the surface area of the roof, road etc. After the tank (6) has been filled to a given volume (V), the water is then automatically discharged to a soakaway. The first water to have drained into the tank (6) is retained for a number of days or is released at a very slow rate. The tank (6) capacity is then ready to receive the first 1-2 mm of rain from the next precipitation.