RECLAMATION OF TIDE AFFECTED LANDS

Abstract

(1) Development of deltas has a history, which Is almost as old as humanity, mainly because of the inherent advantages of a delta like fertility of soil, abundance of water supply and easier means of communication. Due to pressure of population, new pastures were sought and gradually areas$ which were marshes and backwaters were reclaimed for human use mainly agriculture* Through the many projects large or small, executed throughout the world in the past and especially in the present century, land reclamation has gained a larger meaning than just a measure for bringing more land under cultivation, Now it is a complex policy of resource development, contributing to overall economic and social welfare. (2) However$ reclamation of deltas has got its problems: too. Delta build ng ..is a natural process and reclaiming a land prematurely i.i. hen nature is yet to complete its part of reclamation is a costly as well as a risky enterprise. In. Holland and Japan lands as low as 5.0 a below M.3..L, have been reclaimed.' But the recent calamity in Holland by cyclonic storm resulting in breaches in embankments and heavy damage has impetus, to' the new thinking about the correct stage for reclamation, Salinity intrusion is another problem peculiar to deltas# Also the bydraulic structures and embankments constructed in course of reclamation may affect the tidal regime of channels and may induce siltation hampering drainage and navigation# (3) For fruitful planning therefore, investigation is necessary in the realms of Hydrology and Hydrograpby, Geomorphology, Soil Science, Ecology, Agriculture, Social and Economic factors which 1 2 have a bearing on the purposes at development are also very important in this respect. (4) Flood control is the most important measure, which will spell security and will encourage intensive agriculture and industry. Flood control Is necessary against upland and sea-tides or storm surges, Measures will mainly consist of embankments, supplemented by detention reservoirs wherever possible. Agriculture will require soil improvement and water control. While soil aims improvementlat desalinization and other ob,ectives, water control aims at c.roatton of ideal moisture conditions in root lone for plant growth. Agriculture Industry and civic use will require more and more sweet water which may be obtained from river water, canal water or ground .water. (5) Rural development is very Important for the success of land reclamation schemes# tt is not only necessary to treats the requisite conditions for advanced farming, which is essentially a credit operation, but also suitable marketing facilities for the produces This will necessitate a good infrastructure, land consolidation# efficient farm management and helpful agricultural institutions* (6) Economic feasibility is the final test whether a project should be taken up or note Here also we mostly go by the conventional benefit cost ratio, where only the direct benefits are considered. However, since effects of delta development schemes touch the interests and aspirations of the community as a whole, substantial indirect benefits accrue to the society which should have a say in the decisions 47 All the above aspects of reclamation of tide affected lands have been considered in -the dissertation.