A. Must be of adequate size to avoid over flow
B. Must flow under gravity ½ to ¾ full
C. Must be laid at least 2 to 3 m deep to collect /water from the basements
D. All the above
Related Mcqs:
- With self cleansing velocity in sewers___________________?
A. Silting occurs at bottom
B. Scouring occurs at bottom
C. Both silting and scouring occur at bottom
D. Neither silting nor scouring occurs at bottom - At the junction of sewers___________________?
A. Top of smaller sewer is kept lower
B. Top of larger sewer is kept lower
C. Tops of both the sewers are at the same level
D. None of these - For drainage pipes in buildings the test applied before putting them to use, is__________________?
A. Water test
B. Smoke test
C. Straightness test
D. All the above - The formula which accepts the value of rugosity coefficient n = 0.012 to be used in Manning’s formula, is given by______________________?
A. Bazin
B. Crimp and Bruges
C. William-Hazen
D. Kutter - Lead acetate test in sewer manhole is done to test the presence of ____________________?
A. Methane gas
B. Hydrogen sulphide
C. Carbondioxide gas
D. Diesel vapours - The normal values of over flow rates for secondary sedimentation tanks, ranges between__________________?
A. 25,000 to 35,000 litres/sqm/day
B. 40,000 to 50,000 litres/sqm/day
C. 50,000 to 60,000 litres/sqm/day
D. 80,000 to 10,000 litres/sqm/day - Assertion A. : Discharging the effluents from the oxidation ponds just up stream of lakes or reservoirs is undesirable. Reason (R) : The discharged algae get settled in the reservoirs and cause anaerobic decomposition and other water qualities_________________?
A. Both A and R are true and R is the correct explanation of A
B. Both A and R are true but R is not a correct explanation of A
C. A is true but R is false
D. A is false but R is true - Aerobic activity is maximum_______________?
A. In freshly produced sewage
B. At sewer pipes
C. In sewer treatment plants
D. None of these - Pick up the correct statement from the following ?
A. Turbidity is more in strong sewage
B. The black colour indicates septic sewage
C. The sewage omits offensive odours after four hours
D. All the above - The minimum recommended diameter of sewers, is_________________?
A. 5 cm
B. 10 cm
C. 15 cm
D. 20 cm
