In order to assess variations in the sea level due to climatic changes and impact of such variations on the coastal belt of India, a project for the establishment of modern tide gauges for accurate measurement of tides has been initiated. Modern tide gauges at 11 stations i.e. Bombay, Porbunder, Goa, Cochin, Tuticorin, Madras, Machilipatnam, Vishakhapatnam, Paradeep, Calcutta and Kavarati are proposed to be set up. The project also includes preparation of contour maps of the coastal region. The data collected from the tide gauge stations and coastal maps form the basis for developing predictive models for assessing the effect of Mean Sea Level variations and storm surges on the coast.

The activities under this programme include: (i) installation of modern tide gauges and commissioning of tide gauge stations at Bombay, Porbunder, Goa, Cochin, Tuticorin, Madras, Machilipatnam, Vishakhapatnam, Paradeep, Calcutta and Kavarati; (ii) establishment of tidal data center at SOI Dehra Dun; (iii) NIC netting of tide gauge stations; (iv) detailed mapping of the stretches between Nellore to Machilipatnam and Paradeep to Indo-Bangladesh boarder; and (v) development of predictive models on sea level variations, storm-surges etc.

The achievements upto 1994 include; completion of tide gauge cabin construction at Goa, Tuticorin, Madras and Vishakhapatnam and commissioning of the tide gauge stations at Goa and Bombay; modification and improvement of digital version of SOI Float Type tide gauge called Float Type Digital Tide Gauge (FTDTG) which has an accuracy of 3mm; and mapping of the coastal stretch from Nellore to Machilipatnam.

Major activities under this programme during 1994-95 were :

* Construction of tide gauge cabins at Cochin, Kavarati, Machilipatnam and Paradeep.

* Commissioning of tide gauge stations at Tuticorin, Madras, Visakhapatnam and Kavarati.

* Import of 3 acoustic tide gauges for comparison with the indigenously fabricated FTDTG and pressure sensor tide gauge.

* Establishment of a National Tidal Data Centre at Survey of India, Dehra Dun with computers, application softwares, digitizer, plotter, terminals, VSAT etc. for collection and archival of tidal data.

* Completion of coastal area mapping from Nellore to Machilipatnam on 1:25,000 scale with 0.5 metre contour interval upto a height of 6 metres or a minimum distance of 20 k.m. on the landward side.

* Initiation of the modelling component of SELMAM through a project entitled `Sea level variability in the coastal region of India'.