The GATE Grind

GATE Water Resources and Environmental Hydraulics: Surface Water Resources – Previous Year Questions

12 GATE previous year questions on Surface Water Resources (Water Resources and Environmental Hydraulics, Environmental Science and Engineering) with answers and explanations, from every paper.

  1. GATE 2022 ES Q18 (1 mark, Multiple choice) – I: Goodrich reservoir routing is a hydrologic flood-routing method. II: Muskingum channel routing is a hydraulic flood-routing method. Select the…
  2. GATE 2022 ES Q35 (1 mark, Numerical answer) – A triangular2-hour unit hydrograph for 1 cm excess over 540 ha is shown. Find peak discharge in m³/s, to one decimal.
  3. GATE 2022 ES Q56 (2 marks, Numerical answer) – A 3-hour storm covers zones15%,35%,50% with φ-indices .5,1.0,.8 cm/h. Their hourly rainfall triples (cm) are(.4,2.5,1.6),(.8,3.0,2.1),(.6,2.6,1.9).…
  4. GATE 2023 ES Q34 (1 mark, Numerical answer) – An S-hydrograph uses3-hour unit hydrographs for 1 cm excess over 240 km². Find its equilibrium discharge in m³/s, to two decimals.
  5. GATE 2023 ES Q51 (2 marks, Numerical answer) – The catchment Q–S–U–T–Q and gauge positions are shown. Rainfalls P, Q, R, S, U, V are20,25,30,15,22,18 mm. Find Thiessen-weighted mean rainfall in mm,…
  6. GATE 2024 ES Q35 (1 mark, Numerical answer) – A Class-A pan starts a week at 250 mm water depth and ends at 240 mm, with 10 mm rainfall during the week. Pan coefficient is .8. Find lake…
  7. GATE 2024 ES Q55 (2 marks, Numerical answer) – Find watershed-average rainfall from the shown isohyet map, in integer mm.
  8. GATE 2025 ES Q16 (1 mark, Multiple choice) – For flood routing: P Hydrologic routing uses continuity and momentum equations. Q Hydraulic routing uses continuity and energy equations. Choose the…
  9. GATE 2025 ES Q52 (2 marks, Numerical answer) – The shown storm hyetograph produces 12.5 mm direct runoff. Find its φ-index in mm/hour, to two decimals.
  10. GATE 2025 ES Q53 (2 marks, Numerical answer) – Subcatchments P, Q, R, S have areas 750,1000,1500,2000 ha;runoff coefficients .5,.6,.6,.7;and concentration times 1,2,3,4 hours. The catchment and…
  11. GATE 2026 ES Q34 (1 mark, Numerical answer) – A six-hour rainfall of 6 cm has a return period of 40 years at a station. Find the probability of a six-hour rainfall of this or greater magnitude at…
  12. GATE 2026 ES Q56 (2 marks, Numerical answer) – A 100-minute rainfall event has cumulative rainfall (cm) 0,.5,1.2,2.6,3.3,3.5 at times (min) 0,20,40,60,80,100. Initial loss is .6 cm and the -index…