Modify the one-dimensional continuity equation to include rainfall over the free surface

The rainfall run off model HEC-HMS is combined with river routing model. They are used for simulating the rainfall process.

Explanation:

The HEC - HMS rainfall model is used for simulating the rainfall runoff process. In this study the soil conservation service and curve number method is used to calculate the sub basin loss in basin module.

It provides various options for providing the rainfall distributions in the basin. It has the control specification module used to control the time interval for the simulations.

The one dimensional continuity equation is

бA / бT + бQ / бx = 0