Waters Protection Ordinance
(WPO)

Dur­ing con­struc­tion or sub­stan­tial build­ing al­ter­a­tions, the per­sons re­spons­ible for the build­ings must en­sure that pre­cip­it­a­tion wa­ter and per­man­ent flows of non-pol­luted waste wa­ter are chan­nelled off sep­ar­ately from pol­luted waste wa­ter pri­or to reach­ing the out­side of the build­ing.