Correct option is D
(As per IS 1729:1983, Clause 4.6.1.2)
For building drainage pipes flowing half-full, the approximate minimum gradients required to achieve adequate self-cleansing velocity are:
Diameter of Sewer (mm) | Minimum Gradient |
|---|---|
100 | 1 in 57 |
150 | 1 in 100 |
200 | 1 in 145 |
230 | 1 in 175 |
250 | 1 in 195 |
300 | 1 in 250 |
