Abstract:
Water  (chemical  formula:  H2O)  is  a  transparent  fluid  which  forms  the  world's streams,  lakes,  oceans  and  rain,  and  is  the  major  constituent  of  the  fluids  of organisms. As    a  chemical    compound,    a  water    molecule  contains one  oxygen  and  two  hydrogen  atoms  that  are  connected  by  covalent  bonds. Water  is  a  liquid  at  standard  ambient  temperature  and  pressure,  but  it  often  co-
exists  on  Earth  with  its  solid  state,  ice;  and  gaseous  state,  steam  (water  vapour). 
Even  today  man  has  brought  about  changes  whether  through  urbanisation  and growth  of  population   centre  by  introduction  and  employment  of  auxiliary  means in  agriculture  which  has  disturbed  or  destroyed  the  natural  healthy  quality  of water  bodies.