26.5.2. W-Index

Try these first

1. 1.

   What does the W-Index account for in hydrology?

   Hint

   Think about what happens when rain first starts.

2. 2.

   How does using the W-Index improve water management?

   Hint

   Consider the effects of accurate predictions.

3. 3.

   What is the W-Index used for in hydrology?

   • To estimate average infiltration during excess rainfall
   • To measure groundwater levels
   • To calculate evaporation rates

   Hint

   Remember the role of the W-Index during heavy rains.

4. 4.

   True or False: The W-Index only applies to soil types with high porosity.

   • True
   • False

   Hint

   Consider how different soils absorb water.

5. 5.

   Given a rainfall event with an initial loss of 10 mm and an average infiltration rate (W-Index) of 15 mm/hour, calculate how long it will take before runoff begins if the rainfall rate is 30 mm/hour.

   Hint

   Use the effective rainfall to find how long it takes to exceed the infiltration rate.

6. 6.

   Examine a scenario in which the W-Index for a specific area is forecasted to decrease due to urban development. Discuss potential impacts on local water management practices.

   Hint

   Consider how urbanization impacts soil and impervious surfaces.