Water Supply & Sanitation Engineering Online Test – Paper 3

1. The most dangerous metal for human health is

2. Sterilization is the process of

3. The head developed in a centrifugal pump, at zero discharge is known as

4. The suitable system of sanitation for an area having rainfall for only one season is:

5. Water demand for public use as compared to the total demand, kept in the design of waterworks for a city, is

6. The detention time in a septic tank is usually:

7. Water of zero hardness is obtained by

8. The amount of BOD in domestic water should be

9. Gravity conduits are generally in the form of

10. Anti-siphonage pipe is connected to:

11. The main pipes must be designed to carry

12. 2 ml of sewage, having BOD-500 mg/l, is diluted to 200 ml, and incubated for 5 days at 20°C. If the D.O. content after 5 days is found to be 5 mg/l, what was the initial D.O. content of the diluted sample?

13. A circular section of sewer has the advantage of:

14. Which test is a must for a house sewer?

15. Break pressure tank is generally provided in rural water supply schemes if static head exceeds

16. The type of joint used in HDP pipe is

17. The open channels supported above the ground over trestles are called

18. "A right-angled sleeve (valve) connected in the water main through which water is tapped for domestic supply is called:

19. By boiling water, hardness can be removed if it is due to:

20. If the diameter of the main pipe is taken less than the economical diameter, then

21. A manhole of such depth that an access shaft is required in addition to the working chamber, is called.....:

22. Water to the consumers may be supplied from

23. The velocity of water in water mains of 40 cm diameter is usually kept

24. Inspection arm is provided in:

25. Digesters are used for:

26. Merit of water carriage sewage system:

27. The types of pump suitable for water as well as sewage

28. The last trap provided in a house drainage system is:

29. The layout of the distribution system that is suitable for haphazardly growing cities is:

30. Thrash rack/roughing filter is provided at the entrance of

31. Groundwater is generally free from

32. Which is the oldest waterworks in Nepal?

33. For areas of distributed rainfall throughout the year with less intensity, the suitable system of sanitation is:

34. Self-purification of natural streams is caused due to

35. Any trap is intended to trap foul gases with the provision of:

36. The main function of a manhole is:

37. Pressure relief valve is provided to prevent

38. The best sewer material to resist hydrogen sulfide corrosion is:

39. Absolutely soft waters are required for

40. Turbidity is measured on..........

41. The approximate diameter of a water mains for supplying 7.15 mld with 1.21 m/sec velocity flow will be

42. The inlet and outlet pipes of the septic tank are bent:

43. An aquiclude is

44. To determine the velocity of the flow of underground water, the most commonly used non-empirical formula is....formula:

45. Dug wells or open wells

46. Find the BOD with the following data: initial oxygen = 9 PPM, final oxygen = 4 PPM sewage sample 200 ml and diluted sewage = 4 ppm.

47. Manhole is said to be deep if its depth is more than:

48. A structure constructed to remove obstacles in the sewer is known as:

49. Imhoff tank is a:

50. The highest non-scouring velocity in a sewer may be allowed in: