More than any other aspect of environmental degradation, pollution of surface and underground waters due to fertilizers has received greater attention. Water can be broadly classified into four categories: (i) non-flowing such as lakes and ponds; (ii) flowing such as rivers and canals; (iii) river estuaries and (iv) underground water.

Both nitrogen and phosphorous Eutrophication of lakes and ponds leads to excessive growth of aquatic plants (macrophhytes) and algae (phytoplankton), which deplete the water of oxygen and this, may lead to death of fishes and other aquatic animal life. Furthermore, algal and decaying algal and aquatic plant tissue can lead to discoloration and bad odour and this affects recreational and aesthetic water uses.

In India, the highest rate of fertilizer N is in Punjab, where an increase in shallow well waters from 0.04-6.15 in 1975 to 0.31-13.3 mg NO, Nl- in 1988 has been reported. A recent survey in Delhi reported, thus a range of 26-150mg N03-N1-‘ in shallow well water, which very high constitutes a warning.