Sub-Committee on Performance Evaluation of Coastal Protection Works Was Held at Mangalore on 4Th May 2005
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CENTRAL WATER COMMISSION CAUVERY & SOUTHERN RIVERS ORGANISATION BEACH EROSION DIRECTORATE, COCHIN – 682 020 Second meeting of Coastal Protection and Development Advisory Committee (CPDAC) Sub-Committee on Performance Evaluation of Coastal Protection Works Meeting : May 4th 2005 Venue : Mangalore Field Visit : May 5th 2005 A. Summary Record of Discussions of the Meeting The second meeting of the CPDAC Sub-Committee on performance evaluation of coastal protection works was held at Mangalore on 4th May 2005. The performance evaluation of the works in Dakshina Kannada and Udupi Districts of Karnataka were taken up. The field inspection of the coastal areas of these two districts was carried out on 5th May 2005. The following were present in the meeting. CPDAC Sub-Committee Members: i) Dr. T.G.Antony Balan, Chief Engineer, C&SRO, CWC, Coimbatore & Convenor, CPDAC Sub-Committee. ii) Shri Gopal Naik, Executive Engineer, Ports and Fisheries Division, Udupi. iii) Shri J.Chandrashekhar Iyer, Director, BED, CWC, Cochin & Member- Secretary of the CPDAC Sub-Committee. Invitees: i) Shri K.A.Ouseph, DD, BED, CWC, Cochin. ii) Shri L.Shivalingaiah, AEE, Ports & Fisheries Sub-Division, Mangalore. iii) Shri Narayanappa, AEE, Ports & Fisheries, Udupi. iv) Shri K.V. Tantri, AE, Ports & Fisheries Sub-Division, Mangalore. v) Shri T.M.Manche Gowda, AE, Ports & Fisheries Sub-Division, Mangalore vi) Shri L.Prasanna Kumar, AE, Ports & Fisheries Sub-Division, Udupi. vii) Shri Ashoka S.K., AE, Ports & Fisheries Division, Udupi. viii) Shri Vinayak R. Naik, Port Conservator, Karwar. ix) Shri A.S.Rao, JE, Ports & Fisheries Sub-Division, Mangalore. x) Shri Sheshakrishna, JE, Ports & Fisheries Sub-Division, Udupi. xi) Shri H.D.Naik, Adm.Asstt., Port Office, Mangalore. xii) Shri M.Ramaswamy, PA to Director (P&IWT), Karwar. Dr.T.G.Antony Balan, Chief Engineer, Central Water Commission welcomed all the members of the sub-committee and other participants to the meeting. In his introductory remarks, he informed that coastal erosion is a very severe problem experienced by the State of Karnataka along a major part of its coastline. He briefly dealt on CPDAC and its sub-committee on performance evaluation of coastal protection works. He brought to the notice of the participants that Chairman, CPDAC in the 6th meeting held at Pondicherry in April 2004 has constituted a Sub-Committee for performance evaluation of coastal protection works in various States. The Sub-Committee may visit sites in the maritime States and submit its report to CPDAC. Considering the severity of problem, the State of Karnataka has been taken up in this second meeting of the sub- committee being held at Mangalore after Kerala. He informed that two districts of Dakshina Kannada and Udupi in Karnataka are being considered for this meeting. The sub-committee has to discuss and deliberate on the performance evaluation of the coastal protection works carried out in these two districts. The meeting was followed by visit to coastal sites in these two districts. The Executive Engineer, Ports & Fisheries Division, Udupi presented a report. He informed that in Karnataka, until the year 2000, Minor Irrigation Department was handling all works related to coastal protection from sea erosion. Thereafter, the responsibility of coastal protection from erosion was handed over to the Department of Ports & Inland Water Transport under Public Works Department of Government of Karnataka. Director (Ports & IWT), based at Karwar, heads this set-up. The Ports and Fisheries Division, Udupi, under the jurisdiction of Director, Ports & Inland Water Transport, Karwar is responsible for anti sea erosion works in the two districts of Dakshina Kannada and Udupi. The coastal districts of Karnataka are shown in Fig. – 1. The members had detailed discussions with the officials of Ports & Inland Water Transport Department of Karnataka on the coastal erosion problems and protection measures. Shri J.Chandrashekhar Iyer, Director, Beach Erosion Directorate, CWC, Cochin briefly summed up the deliberations. The Ports Division was requested to make efforts to obtain old data/records from Minor Irrigation Department from whom the coastal protection works have been taken over and to systematically document all the information about the coastal processes and coastal protection works of the State. According to National Hydrographer, Dehradun, Karnataka State has 280 km of coastline covering the districts of Dakshina Kannada, Udupi and Uttara Kannada. The details of coastal protection works in Dakshina Kannada and Udupi districts were discussed in detail during the meeting. The coastal chainage of Karnataka State starts from southern most coast towards northwards covering Dakshina Kannada from chainage 0 km to 44 km, Udupi district from chainage 44 km to 138 km and Uttara Kannada district from chainage 138 km to 280 km. Since the year 1990 onwards sea erosion problem in Karnataka State has been a 2 common phenomenon. Properties including precious land and infrastructure along the coast has been lost. This has become a burning issue between the Karnataka Government and general public. Accordingly, Karnataka Government has constructed permanent seawall for a length of 27.668 km at the cost of Rs.38.64 crores in Dakshina Kannada and Udupi districts based on the design supplied by KERS, Mysore. Coastal protection works in many areas have been stopped due to various reasons. Agencies have been fixed for starting the work in some areas. A detailed bar chart showing the details of chainages of completed works, ongoing works and areas selected for taking up the work in future etc. from chainage 0 km to 140 km covering Dakshina Kannada and Udupi districts are appended in Annexure I (Page 1-14). The Dakshina Kannada and Udupi districts of Karnataka lie along the west coast of India, between the lat. 12° 45' and 13° 20' N long. 74° 45' and 74° 53'. The Dakshina Kannada and Udupi coasts are subjected to very strong sea breezes during the non- monsoon months. The sea breezes in the afternoons predominate over the land breezes in the early mornings. The sandy beaches of Dakshina Kannada and Udupi districts coast are low open sandy beaches which are 25 to 100 m in width. The material of the beach is mainly detritus sand and the mean size varies from place to place. In most places, it is fine or medium sand. Rock exposures along the beaches are seen at Someshwara, Surathkal, Mulur, Kaup and North of Malpe. Littoral drift along Dakshina Kannada and Udupi districts are negligibly small. On the Karnataka coast, the littoral drift being negligibly small, the adverse effects of man-made structures have not been serious and have been localised, if any. In Dakshina Kannada and Udupi districts there are a large number of rivers that run parallel to the shore before joining the sea. In the monsoon, with these rivers flowing brim upto the top, the water table would be very high and with the waves also being rough, erosion would be inevitable. BENEFITS ACCRUED The various measures adopted by the Government has also accrued sufficient benefits, which may be enlisted as follows: (i) The shoreline has been more or less in dynamic equilibrium except for certain pockets like Ullal, Hejamady Kodi, Mulur, Thonse, Hangareakkata etc. (ii) At certain places the shoreline has become stable due to the construction of seawalls and breakwaters, such as, for example, the Ullal estuary in Mangalore, Doddakopla in Surathkal etc. 3 (iii) The seawalls at places where built, have not caused any erosion at the same site or at adjoining areas. This indicates that seawalls designs adopted have been proper and suitable for those areas/locations. eg. Bengre in Mangalore, NITK beach in Dakshina Kannada district etc. (iv) There is no ecological damage observed along the coastline anywhere in the two districts, due to construction of seawalls. (v) The seawalls have been provided with passages in between two stretches for access to beach goers and fishermen’s convenience. At many locations, the seawalls were built leaving enough beach in front. As such public along the coast are able to use enough beach width for recreational purposes. (vi) Seawalls have been found to be stable in most locations (except in Kaup and Maravanthe in Udupi district, Sasihithlu in Dakshina Kannada district) and some beach formation has taken place after the seawalls came in place. The people living in these coastal areas have generally benefited from the construction of the seawalls, with greater sense of security for their life and property. STATUS OF MAINTENANCE The seawalls and breakwaters built along the coast need to be maintained periodically. The following observations are made regarding the status of maintenance of seawalls/coastal structures in the areas visited: (i) Rubble mound breakwaters protecting the river mouth at Ullal are in bad shape with crest armour totally vanished at several chainages along the length. They need immediate maintenance and attention. (ii) Seawalls at places such as Sasihithlu, Kaup etc. are in bad shape. Periodic maintenance is necessary here too. (iii) Maintenance is to be taken up both immediately before and immediately after the monsoon. For this purpose proper maintenance funds should be provided by the Government. (iv) Due to poor design and maintenance, seawalls were destroyed extensively at certain chainages at Maravanthe. Both design and maintenance wings of the Department need to be strengthened. This is important else the structures may need to be rebuilt in next 2-3 years. Expert advice may be taken and designs may be revised/improved after consulting experts. The meeting ended with a vote of thanks to the Chair. 4 B. Site Inspection Report The sub-committee undertook field visits of the coastal erosion sites and the protected sites in Dakshina Kannada district in the afternoon of 4th May 2005 and Udupi district on 5th May 2005 (Photo 1).