{"id":1795,"date":"2014-11-04T08:16:13","date_gmt":"2014-11-04T08:16:13","guid":{"rendered":"http:\/\/boer.it\/?page_id=1795"},"modified":"2018-10-01T07:32:59","modified_gmt":"2018-10-01T07:32:59","slug":"first-flush-tanks","status":"publish","type":"page","link":"https:\/\/boer.it\/en\/water-treatment-plants\/first-flush-tanks\/","title":{"rendered":"First flush tanks"},"content":{"rendered":"

First Flush<\/span>Tanks<\/span><\/h1>\n<\/div><\/section>\n

Modular or monolithic rainwater harvesting tanks are used for collecting the first 5 mm of runoff evenly covering a surface.<\/p>\n

The purpose of such tanks is that of storing polluted water and avoiding it immediately flows into the drain. Later, the water held by the tanks is directed, by means of a discharge pump, to the municipal sewage system or, if containing hydrocarbons, surfactants, settleable solids, heavy metals, etc, undergoes treatment in specific systems (e.g. oil separation plants and\/or chemical-physical plants).<\/p>\n

First flush water should be allowed to flow into the municipal system within 24-48 hours of the end of the meteorological event and, anyhow, according to the limits set forth by the entity running the sewer system and the water treatment plant. Such rule applies because, in the event of precipitation, municipal water treatment plants are overloaded with incoming water from mixed sewage and would hence have to purify huge quantities exceeding their treating capacity.<\/p>\n<\/div><\/section>\n\n