Fig.1 Area boundary for design and simulate of 3D model in (A) Phrae groundwater basin and (B)
Upper Chao Phraya groundwater
2. Parameter design
There are mainly four parameters of the simulation model: recharge rate, groundwater uses,
water surface and aquifers hydraulic parameters. Reclassified recharge rate is analysis data from
annual rainfall, hydraulic characteristics of soil, land use, runoff, evatranspiration, water supply and
geology. The estimated groundwater use is calculation from groundwater used for consumption.
Data simulation of surface water is water level, cross section, length and vertical hydraulic
conductivity of Yom River. The horizontal hydraulic conductivity was determined to be 0.5-3.5
meter/day [6] through the river bed and assumes an average sediment thickness of 1 meter
throughout stream. The estimate of aquifer hydraulic parameters involved analysis of hydrogeologic
characteristics (horizontal hydraulic conductivity (Kx,Ky), vertical hydraulic conductivity (Kv),
storage coefficient of aquifer (Sy), storage coefficient (S), and porosity) [7]