1. Just as every water is not suitable for human beings, in the same way, every water is not suitable for plant life. Water containing impurities, which are injurious to plant growth, is not satisfactory for irrigation, and is called the unsatisfactory water.

2. The quality of suitable irrigation water is very much influenced by the constituents of the soil which is to be irrigated. A particular water may be harmful for irrigation on a particular soil, but the same water may be tolerable or even useful for irrigation on same other soil. The various types of impurities, which make the water unfit for irrigation are classified as:

• Sediment concentration in water

• Total concentration of soluble salts in water.

• Proportion of sodium ions to other cations.

• Concentration of potential toxic elements present in water.

• Bicarbonate concentration as related to the concentration of calcium plus magnesium.

• Bacterial contamination.