The duration of contact of chlorine with water before it is served to the first consumer, should be at least________.

20 to 30 minutes

15 to 20 minutes

10 to 15 minutes

30 to 40 minutes

Correct Answer : 20 to 30 minutes

Recently Updated in Water Supply Engineering Questions

Normal values of overflow rate for plain sedimentation tanks in litres/hr/m², generally range between

100 to 250

250 to 500

500 to 750

750 to 1000

Correct Answer : Option (C) : 500 to 750

When gravity and pumping systems of water distribution are adopted, the type of distribution reservoir, is____.

intz tank

elevated tank

stand pipe

ground source reservoir

Correct Answer : Option (B) : elevated tank

If n is porosity, y is specific yield and r is specific retention of any soil, the relationship which holds good, is_____.

n + y = r

y + r = n

n + r + y = 0

n + y + r = 1

Correct Answer : Option (B) : y + r = n