WorksheetsQUIZ 2 | HYDROLOGY 2022
Total questions: 18
Worksheet time: 14mins
A mean annual runoff of 1 sm3 from a catchment of area 31.54 km2 represents an effective rainfall of:
100 cm
1.0 cm
100 mm
3.17 cm
Direct runoff is made of:
Surface runoff, prompt interflow, and channel precipitation
Surface runoff, infiltration, and evaporation
Overland flow, and infiltration
Rainfall, and evaporation
A hydrograph is a plot of:
Rainfall intensity against time
Stream discharge against time
Cumulative rainfall against time
Cumulative runoff against time
The term base flow denotes;
Delayed groundwater flow reacting a stream
Delayed groundwater and snowmelt reaching a stream
Delayed groundwater and interflow
The annual minimum flow in a stream
Virgin flow is:
the flow in the river downstream of a gauging station
the flow in the river upstream of a gauging station
the flow unaffected by works of man
the flow that would exist in the stream if there were no abstractions to the precipitation
The water year in India starts from the first day of:
January
April
June
September
An ephemeral stream
is one which always carries some flow
does not have any base flow contribution
is one which has limited contribution of groundwater in wet season
is one which carries only snow-melt water
An intermittent stream
has water table above the stream bed throughout the year
has only flash flows in response to storms
has flows in the stream during wet season due to contribution of groundwater
does not have any contribution of groundwater at any time
Khosla's formula for monthly runoff Rm due to a monthly rainfall Pm is: Rm=Pm−Lm . Where Lm is:
a constant
monthly loss and depends on the mean monthly catchment temperature
a monthly loss coefficient depending on the antecedent precipitation index
a monthly loss depending on the infiltration characteristics of the catchment
The flow-duration curve is a plot of:
accumulated flow against the time
discharge against time on chronological order
the base flow against the precentage of times the flow is exceeded
the stream discharge against the percentage of times the flow is equalled or exceeded
In a flow-mass curve study the demand line drawn from a ridge in the curve did not interest the mass curve again. This represents that:
the reservoir was not full at the beginning
the storage was not adequate
the demand cannot be met by the inflow as the reservoir will not refill
the reservoir is washing water by spill
If in a flow-mass curve, a demand line drawn tangent to the lowest point in a valley of the curve does not intersect the mass curve at an earlier time period, it represents that:
the storage is inadequate
the reservoir will not be full at the start of the dry period
the reservoir is full at the beginning of the dry period
the reservoir is wasting later by spill.
The flow-mass curve is an integral curve of:
the hydrograph
the hyetograph
the flow duration curve
the S-curve
The total rainfall in a catchment of area 1200 km2 during a 6-h storm is 16 cm while the surface runoff due to the storm is 1.2 x 108 m3 . The ϕ index is:
0.1 cm/h
1.0 cm/h
0.2 cm/h
cannot be estimated with the given data
In India, a meteorological subdivision is considered to be affected by moderate drought if it received a total seasonal rainfall which is:
less than 25% of normal value
between 25% and 49% of normal value
between 50% and 74% of normal value
between 75% and 99% of normal value
An area is classified as a drought prone area if the probability P of occurrence of a drought is:
0.4 < P ≤ 1.0
0.2 ≤ P ≤ 0.40
0.1 ≤ P < 0.20
0.0 < P < 0.20
In the standard SCS-CN method of modelling runoff due to daily rainfall, the maximum daily rainfall that would not produce runoff in a watershed with CN = 50 is about:
65 mm
35 mm
50 mm
25 mm
In the standard SCS-CN method, if CN=73 the runoff volume for a one day rainfall of 100 mm is about:
38 mm
2 mm
56 mm
81 mm
