water management water 31 hydrology 20 water supply engineering 18 permanently sustainable development 15 water pollution 14 water quality 11 more ... environmental management 11 waste water 11 environment 11 vodní zdroje 10 zásobování vodou 10 climatic changes 9 environment protection 9 water structures 9 irrigation 9 water courses 8 waste water treatment 7 kvalita vody 6 towns 6 environmental policy 6 power engineering 5 vodní právo 5 agriculture 5 hydrological cycle 4 sewerage 4 underground water 4 flood control 4 water mains 4 hydraulic structures 3 less ...