Water body and groundwater

A water budget method has been used to estimate the exchange between river and groundwater. According to the water conservation in the riverway, the water exchange is calculated using the following equation:

I - O - E - Q + S = 0 (1)

where, I[M³/T] is the surface water recharge, O[M³/T] is the surface water discharge, E[M³/T] is the evaporation from river water surface, S[M³/T] is the riverway storage, and Q[M³/T] is the interactions with groundwater. E is calculated from meteorological data and water surface area. S is estimated from the empirical relationship with stream flow. The results of river and groundwater interaction will give the boundary conditions for the groundwater model below.

The water table, which was observed in the recent field experiments, was used to describe groundwater flow between groundwater recharge area and discharge area. There are two groundwater observation sections A-A and B-B (Fig. 2). From west to east of each section, it is wetland, irrigation area, river, and irrigation area again. The water table sections could give the relative water head difference between irrigation area and non-irrigation area.