CE-603-A Water Resources Engineering - Dec 2024 Question Paper

Under each question, How to answer lists the points an answer should cover, outlined by CampusPrep from the syllabus. Check the details against your textbook.

1. 7 Marks
   aDiscuss methods to enhance the duty of water in irrigation systems?
   How to answer

   • Define duty, delta, base period and their relation
   • List factors reducing duty
   • Discuss methods: lining, rotation, soil management, crop selection, outlet control
2. 7 Marks
   bThe GCA for an irrigation canal is 20,000 hectares out of which 75% is CCA. The intensity of irrigation is 40% for Rabi and 10% for rice. If kor period is 4 weeks for Rabi and 2.5 weeks for rice, determine the outlet discharge. Outlet factors for Rabi and Rice may be assumed as 1800 ha/cumecs and 800 ha/cumecs. Also calculate delta for each case.
   How to answer

   • Compute CCA = 75% of GCA
   • Compute areas under Rabi and Rice from intensities
   • Compute outlet discharge = Area / Outlet factor for each crop
   • Compute delta = 8.64*B/Duty relation
3. 7 Marks
   aIdentify principal crops and discuss about their respective water requirements?
   How to answer

   • Identify Kharif, Rabi, perennial principal crops
   • State growing seasons and examples
   • Discuss water requirement: consumptive use, delta, duty
   • Compare rice vs wheat vs sugarcane requirements
4. 7 Marks
   bExplain the causes and effects of salt efflorescence and its impact on soil quality and crop productivity?
   How to answer

   • Define salt efflorescence / salinity
   • List causes: waterlogging, poor drainage, arid climate, saline irrigation
   • Explain effects on soil structure and fertility
   • Explain impact on crop productivity and reclamation
5. 7 Marks
   aWhen $3.68$ million $m^3$ of water was pumped out from an unconfined aquifer of $6.2 km^2$ area extent, the water table was observed to go down by $2.6 m$. What is the specific yield of the aquifer? During a monsoon season if the water table of the same aquifer goes up by $10.8 m$, what is the volume of recharge?
   How to answer

   • Define specific yield = volume pumped / (area x drawdown)
   • Compute specific yield from 3.68 million m3, 6.2 km2, 2.6 m
   • Define recharge = specific yield x area x rise
   • Compute recharge for 10.8 m rise
6. 7 Marks
   bDiscuss the necessity of groundwater recharge and methods for improving groundwater storage?
   How to answer

   • Explain groundwater depletion and need for recharge
   • Discuss natural vs artificial recharge necessity
   • List methods: percolation tanks, recharge wells, check dams, rainwater harvesting
   • Benefits for storage improvement
7. 7 Marks
   aExplain various methods for computation of average rainfall over a basin. State the advantages and disadvantages of each method?
   How to answer

   • Describe Arithmetic mean, Thiessen polygon, Isohyetal methods
   • Give formulas and procedure for each
   • State advantages and disadvantages
   • State applicability for basin
8. 7 Marks
   b

   Given below are the ordinates of a unit hydrograph for a storm of 4-hour duration. Find ordinates of flood hydrograph when the maximum flood observed was $400\, m^3/s$ and base flow was $250\, m^3/s$.

   Time (hours)	0	4	8	12	16	20	24
   Flow ($m^3/s$)	0	1500	1200	600	220	80	0

   How to answer

   • Compute peak of flood hydrograph = max flood - base flow
   • Compute multiplying factor = peak / UH peak
   • Multiply UH ordinates by factor to get DRH ordinates
   • Add base flow to get flood hydrograph ordinates
9. 7 Marks
   aDiscuss techniques for estimating missing rainfall data in hydrological studies.?
   How to answer

   • Define missing rainfall data problem
   • Explain normal ratio, inverse distance, regression methods
   • State selection criteria and steps
   • Mention advantages/limitations
10. 7 Marks
    bDefine hydraulic structures and their role in water resource management?
    How to answer

    • Define hydraulic structures
    • List types: dams, weirs, barrages, canals, spillways
    • Explain role in storage, diversion, flood control
    • Link to water resource management
11. 7 Marks
    aFor a channel, the discharge Q, rugosity coefficient N, critical velocity ratio m, and the bed width-depth ratio B/D are given. Explain how would you design the channel using Kennedy's theory?
    How to answer

    • State Kennedy's theory: V0 = 0.55*m*D^0.64 and Q = A*V
    • Use given Q, N, m, B/D ratio
    • Solve trial for depth D and width B
    • Check regime and final section
12. 7 Marks
    bDesign an irrigation canal using Lacey's theory for the following data: Discharge $= 55$ cumecs, Silt factor $= 1.6$, Side slope $= 0.5:1$.
    How to answer

    • Compute Lacey's regime velocity, hydraulic radius, area
    • Determine width, depth, slope using silt factor f=1.6
    • Apply side slope 0.5:1 for final section
    • Summarize designed dimensions
13. 7 Marks
    aDiscuss cost-benefit analysis as a tool for evaluating the effectiveness of flood control projects?
    How to answer

    • Define cost-benefit analysis and B-C ratio
    • List costs and benefits of flood control projects
    • Explain evaluation procedure and decision criteria
    • Discuss limitations
14. 7 Marks
    bExplain how return periods and probability distributions are used to assess flood risk?
    How to answer

    • Define return period T = 1/p
    • Explain probability distributions: Gumbel, Log-Pearson
    • Show use in flood frequency and risk assessment
    • Explain design flood selection
15. 14 Marks
    Write short notes on any two?

    1. a)Wilting coefficient and field capacity
    2. b)Methods for improving groundwater storage
    3. c)Infiltration indices
    4. d)Canal losses and canal lining
    How to answer

    • Select any two topics from list
    • Define key terms and governing concepts
    • Explain significance with examples
    • Add sketches/formulas where relevant