Kirpich Equation Calculator

Calculate Time of Concentration (tc)



Formula

The formula to calculate the Time of Concentration (tc) is:

\[ tc = 0.0078 \left( \frac{L^{0.77}}{S^{0.385}} \right) \]

Where:

What is the Kirpich Equation?

The Kirpich Equation is used to estimate the time of concentration, which is the time it takes for water to travel from the most distant point in a watershed to the outlet. This equation is particularly useful in hydrology for designing drainage systems and understanding flood behavior.

Example

Let's say the travel length (L) is 500 meters, and the slope (S) is 0.05. Using the formula:

\[ tc = 0.0078 \left( \frac{500^{0.77}}{0.05^{0.385}} \right) \approx 2.96 \]

So, the Time of Concentration (tc) is approximately 2.96 minutes.