GATE (CE) 2023 : REVISION QUIZ: HYDROLOGY AND IRRIGATION for ESE & GATE CE Exams

Question 1

The total rainfall in a catchment of area 1000 km² during an 8 hours storm is 24 cm, while the surface runoff due to the storm is 2 × 10⁸ m³. The ϕ-index is ____

Question 2

The mass curve of rainfall for a duration of 100 minute is given below –

Estimate the maximum intensity of rainfall for 20 minute duration of storm.

Question 3

The recorded annual rainfall from five rain gauges statements in a catchment and the corresponding Thiessen polygon areas are as follows:

The scale of the Map is 1 : 40, Find the average annual discharge at the outlet, if the runoff coefficient of the catchment is 0.5.

Question 4Multiple Correct Options

The ordinates of 2 hours unit hydrograph are given in the following table:

A storm of 4.5 cm occur uniformly over the entire catchment in 4 hour. The index is equal to 2.45 mm/hr and base flow is 10 m³/s. then

(Use trapezoidal method of integration)

Question 5

A sediment reservoir is planned for a 2100 sq.m site that has a peak inflow of 120cumec. The runoff from a 4cm rainfall is 2.04cm and the outlet structure has a peak capacity of 50cumec. What is the storage volume needed to handle this storm (in cumec) ? Take ratio of Storage to runoff volume as 0.386

Question 6

A 50 dm diameter well gives a discharge of 0.05 m³/sec. Two observations well were made at a distance of 3 m having drawdown 3 m and at a distance of 9 m having drawdown of 1 m. Bottom of the well is 10 m below the ground water level. The coefficient of permeablity of the medium is

Question 7

A 100 ha watershed received rainfall at a rate of 5 cm/hr for 2 hours. If the runoff generated by the storm was at the rate of 1 m³/s for 10 hours, then the runoff coefficient for the watershed was

Question 8

A canal was designed to meet the irrigation needs of a 2000 haland growing rice of 3360 hrbase period & having delta of 120 cm. If the canal water is used to irrigate wheat of base period 2856 hr and having delta of 60 cm, then the area that can be irrigated is

Question 9Multiple Correct Options

A area of 0.04 hectare is irrigated with help of tubewell with discharge through supply ditch 0.02 cumsec. If f = 15 cm/hr and y_avg = 17cm then time required and maximum area that can be irrigated

(y_avg = avg. depth of water following over the strip)

Question 10

A canal has a flow rate of 4.5m³/sec & has medium size silts with an average grain size of 0.016cm. What will be the velocity through the canal as per lacey’stheory?

Question 11

A rectangular channel having width 2.5 m and depth 1.25 m is constructed to carry water at a slope of 1.945 × 10^-3. What should be the minimum size of bed particle so that no scouring and silting takes place.

Question 12

Following data were obtained from the stability analysis of a concrete gravity dam.

Total overturning moment about toe = 3 × 10⁵ ton-m.
Total resisting moment about toe = 4 × 10⁵ ton–m.
Total downward weight of the dam = 6000 tones
Total uplift force = 1000 tones,
Base width of dam = 50m

Calculate maximum and minimum pressure on the soil.

Question 13

If the path of an irrigation canal is below the level of a natural stream, the type of cross drainage structure provided is

Question 14

The ordinate of the uplift pressure at a point is found to be 2.8 m while designing the downstream floor thickness of a weir. If the relative density of concrete is 2.4 then the design thickness of the floor to be provided for resisting uplift pressure without accounting safety factor is

Question 15

Group I contains three broad classes of irrigation supply canal outlets. Group II presents hydraulic performance attributes.

The correct match of the items in Group I with the items in Group II is