When is a land considered “water – logged” ?

Waterlogging occurs when there is too much water in a plant's root zone, which decreases the oxygen available to roots and Capillary fringe reaches the root zone of the plant.
Waterlogging can be a major constraint to plant growth and production and, under certain conditions, will cause plant death.
Waterlogging is caused by a combination of excess rainfall (for the site), poor external drainage (runoff), poor internal drainage (water movement in the soil profile), and the inability of the soil to store much water.
An area is known as waterlogged when drainage by gravity stops.

• Various Ways of Preventing Waterlogging:
Control the Loss of Water. The seepage loss from the canals can be reduced by a number of measures.
Augmenting Outflow and Preventing Inflows.
Disposing of the Rainwater.
Preventing the Loss of Water.
Not Using Alkaline Water.
Raise the Beds.
Install Proper Drainage Systems.
Mulching.