Question

What is the process of measuring water discharge in rivers and streams?

• A. Rain gauging
• B. Infiltration measurement
• C. Stream gauging
• D. Transpiration monitoring

Hint:

• Stream gauging (or streamflow measurement) is the process of quantifying the discharge (flow rate) of water in rivers and streams.
• Common methods include the velocity-area method, dilution gauging, and use of weirs/flumes or rating curves.
• Rain gauging measures rainfall.
• Infiltration measurement measures water entry into soil.
• Transpiration monitoring measures water release from plants.

Answer 1

The Correct Option is C

Stream gauging is the correct process for measuring water discharge in rivers and streams. This involves quantifying the volume of water flowing through a cross-section of the stream or river per unit time. Stream gauging is a critical component in the study of hydrology and water resource management.

The key steps involved in stream gauging are as follows:

• Selection of Site: Choose a stable, straight section of the river or stream with a uniform cross-section to ensure accurate measurements.
• Cross-sectional Survey: Measure the depth and width of the stream at regular intervals to determine its shape.
• Measurement of Water Velocity: Use a current meter or Acoustic Doppler Current Profiler (ADCP) to measure the speed at which water flows at different points across the cross-section.
• Calculation of Discharge: Apply the continuity equation: Q = A × V, where Q is the discharge, A is the cross-sectional area, and V is the average velocity of the water. Sum these products for all sections across the stream to determine total discharge.

Stream gauging data help in flood forecasting, managing water resources, and understanding ecological health of aquatic environments.