Gujarat Provincial Municipal Corporations Act, 1949
Whenever it is provided in this Chapter that steps shall or may be taken for the effectual drainage of any premises, the Commissioner may require that there shall be one drain for sullage, excrementitious matter and polluted water and another and an entirely distinct drain for rain water and unpolluted sub-soil water or for both rainwater and unpolluted sub-soil water, each emptying into separate municipal drains or other places legally set apart for the discharge of drainage or other suitable places.