The sewerage from stables, cowsheds, dairies, market-places, abattoirs, area for washing vehicles and other places of a like nature shall be connected to a public sewer or, if such is not available, to private treatment and disposal plants or to conserving-tanks, and, in addition, the following requirements shall be complied with—

a) provision shall be made, to the satisfaction of the local authority, for the prevention of entry of rain-water into such public sewer, private treatment and disposal plants or conserving-tanks, either by roofing the area used for the above purposes or by other approved means;

b) the place to be connected shall be paved and graded to the satisfaction of the local authority;

c) the private sewer serving such place shall be provided with an effective silt-trap or petrol-trap or grease-trap with removable grating.