Description : For estimating the peak run off the rational formula Q = 0.0278 KpA was evolved by A. Kinchling B. Lloyd Davis C. Frubling D. All the above
Last Answer : ANS: D
Description : Pick up the correct statement from the following: A. The maximum rate of storm runoff is called peak drainage discharge B. Rational method of estimating peak run off, may be used precisely for ... entire area starts contributing to the runoff, is called the time of concentration D. All the above
Description : When drainage to sewage ratio is 20, the peak dry weather flow is A. 20% of the design discharge B. Slightly less than 5% of the design discharge C. Slightly more than 5% of the design discharge D. None of these
Last Answer : ANS: B
Description : In a city the ratio of the drainage to sewage is 20, the percentage discharge passing through non-monsoon periods, is A. 5 B. 10 C. 15 D. 20
Description : Pick up the in-correct statement from the following: A. Manholes are provided in sewer pipes at suitable intervals B. Catch basins are generally provided in sewers for carrying drainage discharge C. Inlets are generally provided in all sewers D. None of these
Last Answer : ANS: C
Description : For a peak discharge of 0.0157 cumec, with a velocity of 0.9 m/sec, the diameter of the sewer main, is A. 10 cm B. 12 cm C. 15 cm D. 18 cm
Description : A cylindrical ejector having its height 2 m fills after every 10 minutes with a peak sewage discharge of 0.0157 cumec. The diameter of the ejector chamber, is A. 2.30 m B. 2.40 m C. 2.45 m D. 2.50 m
Description : If the peak discharge of a storm water drain (S.W. Drain) is expected to exceed 150 cumecs, the free board to be provided, is A. 100 cm B. 90 cm C. 80 cm D. 50 cm
Last Answer : ANS: A
Description : The drainage area of a town is 12 hectares. Its 40% area is hard pavement ( K = 0.85), the 40% area is unpaved streets (K = 0.20) and the remaining is wooded areas (K = 0.15). Assuming the time of concentration ... 60) the maximum run off is A. 0.10 cumec B. 0.12 cumec C. 0.15 cumec D. 0.20 cumec
Description : If is the rugosity coefficient, is the bed slope of sewer, the velocity of flow in m/sec may be obtained by the formula V = (1/n) r2/3 s1/2 evolved by A. Chezy B. Manning C. Bazin D. Kutter
Description : The most effective arrangement for diverting excess storm water into a natural drainage, is A. Leaping weir B. Overflow weir C. Siphon spill way D. None of these
Description : For house drainage minimum gradient is A. 1 in 60 B. 1 in 80 C. 1 in 10 D. 1 in 400
Description : If D.O. concentration falls down to zero in any natural drainage, it indicates the zone of A. Degradation B. Active decomposition C. Recovery D. Cleaner water
Description : The stone ware sewers A. Are used for carrying sewage and drainage from houses B. Are manufactured from clays and shale C. After casting are dried and burnt at temperature 150°C, 700°C and 1200°C D. All the above
Description : 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
Description : The gas evolved in sewers is A. Carbondioxide B. Hydrogen sulphide C. Methane D. All of these
Description : The lag time between precipitation period and peak discharge period of a river: w) is increased by urbanization x) is decreased by urbanization y) is shorter for a large drainage basin than for a small one z) depends upon the hydraulic heads
Last Answer : ANSWER: X -- IS DECREASED BY URBANIZATION
Description : If P is population of a city in thousands and Q is fire demand in litres per minute, for proper estimate of water, the Empirical formula Q = 1135 [(P/5) + 10] is suggested by (A) National Board of fire under-writers (B) Freeman (C) Kuichling (D) None of these
Last Answer : (B) Freeman
Description : The sewage discharge in a detritus tank of a treatment plant is 576 litres/sec with flow velocity of 0.2 m/sec. If the ratio of width to depth is 2, the depth is A. 100 cm B. 110 cm C. 120 cm D. 150 cm
Description : The gradient of sewers depends upon A. Velocity of flow B. Diameter of the sewer C. Discharge D. All the above
Description : The ratio of design discharge to the surface area of a sedimentation tank is called A. Surface loading B. Overflow rate C. Overflow velocity D. All of these
Description : Clogging of sewers, is caused due to A. Silting B. Low discharge C. Greasy and oily matters D. All the above
Description : The effluent of a septic tank is A. Fit for discharge into any open drain B. Foul and contains dissolved and suspended solids C. As good as that from a complete treatment D. None of these
Description : The sewer which collects the discharge from a collecting system and delivers it to a treatment plant, is known A. House sewer B. Lateral sewer C. Branch sewer D. Sewer outfall
Description : The density of population over 40 hectares is 250/hectare. If water supply demand per day is 200 litres and sewage discharge is 80% of water supply, the sewage flow in sewers of separate system, is A. 0.05552 cumec B. 0.05554 cumec C. 0.05556 cumec D. 0.0556 cumec
Description : If the discharge of a sewer running half is 628 1.p.s., i = 0.001, and n = 0.010, the diameter of the sewer, is A. 1.39 m B. 1.49 m C. 1.59 m D. 1.69 m
Description : For design of sewers, percentage of sewage discharge is assumed A. 65 to 70% B. 70 to 75% C. 75 to 80% D. 85%
Description : In a sedimentation tank (length L, width B, depth D) the settling velocity of a particle for a discharge Q, is A. Q/(B × D) B. Q/(L × D) C. Q/L D. Q/(B × L)
Description : The sewer which received discharge from two or more main sewers, is known as A. A trunk sewer B. An outfall sewer C. A main sewer D. An intercepting sewer
Description : ¾th or ¼th extra space is left in sewer pipes at maximum discharge for A. Low estimates of the average and maximum flows B. Large scale infiltration of storm water C. Unexpected increase in population D. All the above
Description : Sewer pipes are designed for maximum discharge with 25% to 33% vacant cross-sectional area for A. Unexpected large scale infiltration of stream water B. Unexpected increase in the population C. Under estimates of maximum and average flows D. All of the above
Description : For the open drain (N = 0.025) shown in the below figure, the discharge is A. 26.88 cumecs B. 27.88 cumecs C. 28.88 cumecs D. 29.88 cumecs
Description : The discharge per unit plan area of a sedimentation tank, is generally called A. Over flow rate B. Surface loading C. Over flow velocity D. All the above
Description : The sewer pipes A. Carry sewage as gravity conduits B. Are designed for generating self-cleansing velocities at different discharge C. Should resist the wear and tear caused due to abrasion D. All the above
Description : Pick up the correct statement from the following: A. The sewer pipes of sizes less than 0.4 m diameter are designed as running full at maximum discharge B. The sewer pipes of sizes greater than 0.4 m ... discharge C. The minimum design velocity of sewer pipes is taken as 0.8 m/sec D. All the above
Description : In Chezy’s formula V = C rs for calculating the velocity of flow in circular sewer of diameter running full, the value of hydraulic mean radius is A. D B. D /2 C. D/3 D. D/4
Description : The formula V = (1/n) r2/3 A. Chezy’s formula B. Bazin’s formula C. Kutter’s formula D. Manning’s formula
Description : The value of Chezy’s constant C = 157.6/(1.81 + K/ ) is used in A. Chezy’s formula B. Bazin’s formula C. Kutter’s formula D. Manning’s formula
Description : Hazen’s formula VS = 418 (GS – Gw)d [(3T + 70)/100] is used for the settlement velocity of the particles of diameter A. Less than 0.01 mm B. Less than 0.05 mm C. Less than 0.1 mm D. Greater than 0.1 mm
Description : 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
Description : depends upon The Chezy’s constant C in the formula V = C A. Size of the sewer B. Shape of the sewer C. Roughness of sewer surface D. All the above
Description : The aqueduct or super-passage type of works are generally used when (A) High flood drainage discharge is small (B) High flood drainage discharge is large and short lived (C) High flood drainage discharge is large and continues for a long time (D) None of the above
Last Answer : Answer: Option A
Description : Before discharging the foul sewage into rivers, it is generally treated by A. Screening B. Sedimentation C. Oxidation D. All the above
Description : Sewer manholes are generally provided at A. The change of gradient B. The change of direction C. The junctions of sewers D. All of these
Description : In 1000 kg of sewage, the total solids approximate A. 0.5 to 1.0 kg B. 1 kg to 2.0 kg C. 5 kg to 7.5 kg D. 7.5 kg to 10 kg
Description : Aerobic activity is maximum A. In freshly produced sewage B. At sewer pipes C. In sewer treatment plants D. None of these
Description : If the diameter of a sewer is 100 mm, the gradient required for generating self cleansing velocity is A. 1 in 60 B. 1 in 100 C. 1 in 120 D. None of these
Description : hydraulically equivalent, the relationship which holds good, is A. D8/3 = 4 b8/3 B. D3/8 = 4 b3/8 C. D2/3 = 4 b2/3 D. D3/2 = 4 b3/2
Description : To test chemical oxygen demand (C.O.D.) of sewage, organic matter is oxidised by potassium dichromate in the presence of A. Hydrochloric acid B. Sulphuric acid C. Nitric acid D. Citric acid
Description : Sewer pipes need be checked for A. Minimum flow B. Maximum flow C. Both A. and B. D. None of these