13.6. Derivation of DDF Curves

Try these first

1. 1.

   What is the formula to derive DDF curves?

   Hint

   Think about the basic relationship between rainfall depth, intensity, and duration.

2. 2.

   Why is it important to derive DDF curves from IDF curves?

   Hint

   Consider which data is critical for water balance studies.

3. 3.

   What is the primary formula to derive DDF curves?

   • Intensity ÷ Duration
   • Depth = Intensity × Duration
   • Depth ÷ Intensity

   Hint

   Think about how each component interacts.

4. 4.

   True or False: DDF curves can represent only rainfall intensity.

   • True
   • False

   Hint

   Consider what DDF stands for.

5. 5.

   A storm produces an intensity of 75 mm/hr for 45 minutes. Calculate the rainfall depth and contextualize how this depth could affect local waterways.

   Hint

   Convert minutes to hours before performing the multiplication.

6. 6.

   Consider a catchment area that receives an IDF indicating an average intensity of 50 mm/hr for a storm lasting 2 hours. How does this example illustrate the use of DDF curves?

   Hint

   Again, remember that depth is key in DDF applications.