globally and considering the hydraulic cycle, water is in constant motion from the land surface to the atmosphere and from atmosphere to the ground or land surface. run off is experienced when heavy rains are experienced. this run off normally erodes loads of silt sediments and this mixes with streams, lakes and pollutes surface water (chang 2004). in china due to industrialisation, the water cycle has been tempered with. this is due to production of toxic compounds like oxides of carbon and sulphur which react with water forming complex. there is massive deforestation which has led to reduction in transpiration. there is a general shortage of quality water globally due to increasing population and industrialisation