Groundwater Model for the Netherlands. Mathematical Model Development and User's Guide

Abstract

This publication discusses the computer program development of the "Groundwater Model for the Netherlands (LGM)". The publication is also intended to be a user's guide. It describes the various steps to be taken and procedures to be observed throughout the modelling process while applying LGM. LGM is a coupled system of so-called AQ-computer program packages and the Geographic Information System (GIS). The communication between the AQ-environment and the GIS-environment is based on ASCII files. The AQ programs are based on the numerical technique of finite elements (triangles and quadrilaterals). The saturated multi-aquifer geohydrological system consists of a series of aquifers separated by aquitards. Presently, the main output of simulations with LGM are maps of groundwater heads in aquifer, flux between the upper boundary of the geohydrological system and the top system, and fluxes across the aquitards. LGM can be used to assess the effect of various stresses upon the geohydrological system, for example due to changes in groundwater abstraction. LGM proves to be an efficient and versatile tool to address various types of geohydrological problems.