Chennai: State agricultural engineering department has taken up a first-of-its- kind land reclamation project to fight saline intrusion and soil restoration in Cuddalore district where several hectares of agriculture land is now saline due to drought and sea water intrusion.
“Due to over exploitation of land and water resources, the soil has started testing with high alkali and saline content and in some areas acidification is also reported. Adoption of scientific intervention and management is now under to bring more area under cultivation during the ensuing monsoon,” said state agricultural department secretary Gagandeep Singh Bedi.
In Cuddalore field drains are supposed to discharge rainwater and flood water but due to two years of drought the land has become fallow with salt sedimentation.
Seawater during high tides reverse in to the fields and the entire fields are invaded with salt water. The farmers could not cultivate crops in the past two years and now the salt water entry is to be blocked through bed dams. Agriculture engineering department is executing the project and the farms are to be treated shortly, Bedi said.
For Cuddalore district, location specific interventions is done to increase the soil fertility and productivity is being implemented in an area of 1,100 Hectare with an outlay of Rs 6.67 crore, the top officer said adding that based on the success of the project the scheme is to be continued in Kancheepuram, Villupuram, Ramanathapuram, Tirunelveli and Thoothukudi districts which have more area affected by saline and alkaline problems with an outlay of Rs 10.50 crore.
The sea water intrusion is a major issue in northern districts where the rivers are dry for most of the time resulting in reverse flow of sea water. The state is taking efforts to restore the agricultural land, but if the north bound rivers like Gadilam, Palar and Coleroon are protected the river ecosystem will protect the farmland and also arrest sea water intrusion, opined conservationist K. Brinda of Biuodiversity Conservation Foundation.
How the technique works
The saline water intrusion is arrested and the fresh water is seen about half a foot below the sill level of bed dam while on the seaside, the water level is above the sill level at more than half of the shutter slab height. So more than a foot of seawater is above the fresh water. If this structure is not there the seawater would have invaded the channel making the whole contents saline. Instead of concentrating on the fields alone for reclaiming the salinity, first priority is given to block the entry of saline water and other field reclamation measures are taken subsequently.
