TY - BOOK AU - Witmer m.c.h.dr TI - Integral Water Management At Regional Level PY - 1989/// CY - Nethelands:Rijkswaterstaat Communications KW - WATER MANAGEMENT N1 - 1.Intoduction 2.Assessment of the interests involved in water management 2.1Introduction 2.2Integral planning of water management at national level 2.3Integral planning of water management at regional level 2.3.1System approach to water managemant in Gelderland 2.3.2The drinking water supply in South Holland 2.3.3Groundwater abstraction in West Utrecht 2.3.4Infiltration in the Veluwe 2.4Recent developments in integral water menagement 2.5discussion 3.Elaboration of the problemd involved in water management in the Gooi-Vechtstreek region 3.1Basc premises and choices 3.2Historical background to water management in the Gooi and the Vechstreek 3.2.1Reclamation,peat cutting,excavation and water level management 3.2.2Withdrawals of groundwater 3.2.3Sewage discharger 3.2.4Other sources of pollution 3.2.5Quality of the supplemental water 3.2.3Changes in flora and vegetation in the Vechstreek 3.2.7Changes in the groundwater quality in the Gooi 3.3Conclusions 4.Geology and geohydrology of the Vechtsreek and the Gelderland Valley 4.1Geological history and lithological structure 4.1.1The Pleistocene 4.1.2The Holocene 4.2Geohydrological schematisation 4.2.1Geohydrological shematisation of the Vechtstreek 4.2.2Geohydrological shematisation of the Gooi 4.2.3Geohydrological schematisation of the Gelderland Valley 4.3The deviration of the geohydrological parameters 4.3.1The transmissivity of the aquatards 4.3.The vertical flow resistance of the covering layer 4.4The surface water system; 5.A simulation model of the groundwater and surface water system in the Gooi and the adjacent Vechtstreek 5.1Introduction 5.2Description of the system 5.3Model schematisations 5.3.1Groundwater flow in the aquifers 5.3.2Groundwater flow in the aquitard 5.3.The flow between the first aquafer and the top system 5.3.4The flow between the first aquifer and teh surface water system 5.3.5Division of the model region into homogeneous units 5.3.6Boundry conditions 5.3.6.1Demarcation of the model region 5.3.6.2Determination of the boundary hydraulic heads 5.3.6.3Polder water levels 5.37The preciptation excess 5.3.8Withdrawals and artificial infiltration 5.3.9The surface water system 5.4The formulation and solution of the finite element equationa 5.5Model calibration and verification 5.5.1The construction of a representative regional piezometric surface 5.2.2The representative withdrawals 5.5.4Calibration results 5.5.5Model verification 5.6Sensitivity analysis 5.7Discussion 5.7.1The model schematisation 5.7.2The representative withdrawals 5.5.4Calibration results 5.5.5Modelverification 5.6Sensitivuty analysis 5.7Discussion 5.7.1The model Shematisation 5.7.2The shematisation of the area studied 5.7.3Discretisation 5.7.4Conclusions 6.Simulations 6.1Introduction 6.2Variation of the preciptitation deficit on the water demand in polders 6.4Reduction of the groundwater withdrawals in the Gooi 6.5Raising the water level in the polders around the Naardermeer 6.6Redistribution of the availble surface water 6.7Raising the water level in the Horstermeer polder 6.8The influence of Souththern Flevoland 6.9The situation around 1910 6.10Conclusions 7.The quality of the groundwater in the Gooi 7.1Infiltration areas 7.2Availble data on groungwater quality 7.2..1Archive data 7.2.2Field measurements 7.3Results 7.3.1chloride 7.3.2Nirate-N and Ammonium-N 7.4Discussion and conclusions 8.Discussion and conclusions 8.1The Groundwater model 8.2Gaps in knowldege and in the use of knowledge for outlining a policy 8.3Prospects for thr vegetation in the Vechtstreek. 9.Summary 10.Samenvatting ER -