9.1. Assumptions

Try these first

1. 1.

   What is runoff?

   Hint

   Think of where rainwater goes after it rains.

2. 2.

   Name two types of runoff.

   Hint

   Consider how water travels over and through the ground.

3. 3.

   What is the equation used in the SCS-CN method?

   Hint

   Look for the components of rainfall and retention.

4. 4.

   True or False: Base flow contributes to river discharge during wet periods.

   • True
   • False

   Hint

   Think about what maintains rivers when it hasn't rained.

5. 5.

   A region with urban land use receives 50 mm of rainfall. The Curve Number for this area is 75. Calculate the runoff using the SCS-CN method.

   Hint

   Ensure to convert values correctly when applying the equation.

6. 6.

   Construct a theoretical hydrograph for a watershed with both sandy and clay soils receiving heavy rainfall. Describe the differences in shape you expect to see.

   Hint

   Think about how soil texture impacts movement of water.