A 6 – hour storm has 6 cm of rainfall and the resulting runoff was 3 cm. if the ϕ index remains at the same value, which one of the following is the runoff due to 12 cm of rainfall in 9 hours in the catchment?
1
4.5 cm
2
6.0 cm
3
7.5 cm
4
9.0 cm
A 6 – hour storm has 6 cm of rainfall and the resulting runoff was 3 cm. if the ϕ index remains at the same value, which one of the following is the runoff due to 12 cm of rainfall in 9 hours in the catchment?