Sewage and rain water drains to be distinct

Wherever it is provided in this Chapter that steps shall or may be taken for the effectual drainage of any premises, it shall be competent to the Commissioner to 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 rain-water and unpolluted sub-soil water, each emptying into 299[Board sewer and Municipal drain respectively] or other places legally set apart for the discharge of drainage.