Surinder Sud: Reclaiming the land

FARM VIEW

Irrigation has not been an unmixed blessing. Unless managed judiciously, it can prove counter-productive by causing water logging and soil salinity, resulting, ultimately, in conversion of good land into a wasteland. The latest estimates indicate that over 5.6 million hectares of irrigated land has already been afflicted with the problem of water logging and soil salt salinity. This represents nearly 16.6 per cent of the irrigation projects' total command area.

The loss of agricultural production due to this menace has been assessed by the Karnal-based Central Soil Salinity Research Institute (CSSRI) at a whopping Rs 20,000 crore a year. This is based on the assumption of an annual crop output worth Rs 30,000 a hectare from the irrigated land. Indeed, the real extent of loss is much more if we also take into account the interest cost of the estimated average investment of around Rs 100,000 a hectare that goes into providing irrigation.

Worst still, the area affected by these ills continues to increase for various reasons, including lack of adequate drainage and flawed water pricing policies. In a state like Gujarat, over 20 per cent of the irrigated acreage has gone out of production, totally or partially, due to water logging and salt accumulation. The extent of the affected area varies in other states from 1.5 per cent to 20 per cent. If this trend continues unabated, the country would soon have millions of hectares of wet deserts.

These numbers make it imperative to make liberal investments not only in the measures aimed at preventing water logging and soil salinity but also in reclaiming the lands that have already been affected by it. In the past, the provision of drainage along with that of irrigation was the only managerial intervention available for curbing this menace. But now the CSSRI has developed several technologies for preventing this menace and even reclamation of water and salt affected lands. These techniques are simple, effective and situation-specific.

The details of these techniques with practical tips for their field application have been brought out by the CSSRI in a publication titled Reclamation and management of salt-affected soils. The institute also provides consultancy services for undertaking land reclamation work.

Significantly, most of these technologies are not only cost effective but have high benefit-cost ratio of more than one to make their application economically justifiable. The institute experts maintain that the internal rate of returns on any investment on deploying these technologies is invariably higher than what the commercial banks offer on the term deposits. Significantly, millions of tonnes of additional agricultural production could be obtained by redeeming these lands.

This apart, restoration of soil health results in several other benefits as well which may be difficult to assess in monetary terms. For instance, work related to land reclamation generates between 118 and 303 man-days of employment per hectare. The industry engaged in making equipment and other material needed for this purpose gets nearly 60 per cent share of the total investment. Once the land starts supporting crops, it creates further employment potential down the line. As such, it helps curtail out-migration of people from villages. Moreover, the value of the land immediately shoots up.

However, since adequate drainage is a critical component of any land reclamation strategy, the disposal of the drained out water can pose problems, especially because it also carries salts in varying concentration. While the relatively less saline water can in some cases be reused for various purposes, that with high salt content has to be disposed of by other means. The best way is to put this water into perennial rivers in a regulated manner, keeping in view the river flow. Otherwise, it may require construction of water evaporation tanks. But in areas where such solutions are not feasible, digging of drainage canals may be required which essentially involves public investment.

The CSSRI has suggested creation of a unified apex organisation to deal with all the problems and solutions related to land salinity. This body could integrate the activities like monitoring of the problem; preparation of strategies for its prevention and control; undertake surface and sub-surface drainage works; and other measures to restore the soil productivity. The institute, on its part, has offered to train the manpower for this purpose.