In 2010-2012, the hydrogeological model (HM) of Latvia LAMO was established by scientists of Riga Technical University. The model will be applied for management of water resources of Latvia. The 3D-body of LAMO is approximated by the 95160125 size finite difference grid. Its plane approximation step is 500 metres and LAMO accounts for 25 geological layers that represent the active groundwater zone of the country. The commercial program Groundwater Vistas (GV) is used for running LAMO. GV includes the MODFLOW program that is worldwide applied for development of HM. Novel methods were used to develop LAMO. They took part in performing the following tasks: creating geometry of HM; arrangement of various boundary conditions (digital terrain map, hydrographical network, infiltration flow, conditions on the HM shell surface); calibration process of HM.