Water for people.pdf - WHO Thailand Digital Repository

6 6 / A L O O K A T T H E W O R L D ’ S F R E S H W A T E R R E S O U R C E SThe Natural Water CycleThis groundwater combined with surface water forms the world’sfreshwater resource; renewable but also finite and vital not only tohuman systems but also to the terrestrial environment.The existence of springs and other sources of water have playeda major role in determining human settlement. Rivers and lakesprovided routes for transport of goods and people, later supplementedby canals. Falling water provided and continues to provide power forindustry. Today, water is employed for a wide variety of differentpurposes: desalination, recycling and reuse of wastewater, rainwaterharvesting and similar non-conventional methods provide or add to theresource in certain localities. The value of water, its cost, competitionbetween different uses including its cultural and aesthetic aspects, alladd further dimensions to the consideration of water resources.