What is Water Logging ?
When water table reaches upto or near to ground level then such a land is called as water logged. Due to water logging productivity of land gets affected. Water logging can be also referred as saturation of soil with excess of water.
Effects of water logging :
1. Creation of anaerobic conditions near the root zone :
Excess of water prevents circulation of air. This will destroy bacteria which will thrive oy under aerobic conditions and ultimately leads in reduction of nitrates and other chemicals and thus affects the yield of crops.
2. Normal cultivation operations such as tilting, ploughing cannot be easily carried out.
3. Water logging leads to salinity
Various salts comes to the ground surface along with water resulting in deposition of salts in root zone of crop. Concentration of these salts has a corroding effects on the roots, which reduces osmotic activity of the plants and thus reduces the plant growth and the plants ultimately fades away. Such soil is called as saline soil.
Also Read : Bearing Capacity of Soil and Its Importance
Causes of water logging.
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Over and intensive irrigation.
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Improper drainage of the surface runoff which results in rise in water table by percolation.
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Infiltration of water into soil from nearby rivers.
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Nature or subsoil which may not allow free and easy flow of subsoil water.
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Seepage of water from canals.
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Submergence of the area by floods.
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Excess of rainfall.
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Irregular or flat ground profile.
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Bad effect on community health due to damp climate and breeding conditions for mosquitoes.
Methods to control water logging.
1. Adequate surface drainage :
Quick removal of rain water by suitable surface or open drain is very important measure.
2. Efficient under-drain :
Providing tile drains at suitable depths below the surface of the ground to dispose of excess of subsoil water.
3. Controlling loss of water by seepage from the canals :
This includes lowering the F.S.L of the canal. By lining the canal with suitable impervious material. By using irrigation water economically and keeping the intensity of irrigation flow.
4. Increasing the outflow and preventing the inflow :
This is effected by improving the flow conditions of the existing natural drainage and providing artificial open or subsurface grid.
5. Changing the system of irrigation :
If the system of irrigation is not proper for the given area then it is very much important to change the irrigation system as per the conditions
6. Pumping out surplus water :
To prevent the water logging of land it is very much important to pump out the excess of surplus water from time to time to maintain the fertility and productivity of the land.
7. Prevention of seepage from reservoir :
Reservoir’s should be properly maintained to prevent the seepage of water from the reservoir.
8. Lining of field channels :
Proper lining of canals and channels should be done. If the channel is made proper watertight by providing lining then seepage loss can be reduced upto quiet extent.
Also Read : Footing design considerations