Section 31(1)(b) in The Faridabad Complex Water-Supply Bye-laws
(b)The overflow or warning pipe shall be fixed in an exposed and conscious position where the discharge of water can be readily seen. The outlet of every warning pipe shall not be less than 60 cm. above the gully over which the same may be fixed. All warning pipe unions shall not be less than 20 cm scrowed to Indian Standard threads, so fixed that the bottom of the pipe shall be 25 mm above top water level.