ENVIRONMENTAL STUDIES OF THANGASSERI FISHING HARBOUR

Funding Agency: Harbour Engineering Department, Government of Kerala

Kerala has a coastal stretch of about 590 Kms and is characterised by the presence of lagoons, kayals, estuaries and coastal dunes. The increased rate of urbanisation and developmental activities along the Kerala coast have resulted in various environmental problems like coastal erosion, coastal pollution coastal flooding, salt-water intrusion and silting of waterways and harbours etc. Thus it has become highly imperative that before any developmental or constructional activity is implemented, a detailed study of its likely impact on environment is carried out.

The Fisheries Department and Harbour Engineering Department of Kerala have taken up various developmental activities to improve the economic status of the fishermen community to increase the fish catch and production. Thangasseri Fishing Harbour Project is unique in the sense that it is aimed to cater the traditional fishermen. Thangasseri, located in the Kollam district, is a promontory sheltering a deep cove. The coastal geomorphology and the comparatively calm and deeper hydrography of Thangasseri area coupled with the flourishing economic activity of old Kollam town have attracted fishermen of adjoining villages. This study was aimed at the analysis of the likely impact of Harbour Construction as per the design and to suggest a management plan. The detailed objectives of the project were to study the various aspects of environment like landuse, geomorphology, vegetation and water resources, to study the water quality of the estuary, to study the sewage and drainage problems of the area, to identify the impact of breakwater and finally to suggest an Environmental Management Plan to overcome the possible impacts. Considering various Physical and Socio-economic determinants a zone of 360-metre width towards the land from the present shoreline with an area of 2 sq.km. was identified as the Impact Zone of Harbour Construction. This area is heavily populated with an average density of 1600 persons per sq.km.

Land resources of the impact zone were analysed. The various environmental aspects like landuse, geomorphology, assets, vegetation etc., were thematically represented and superimposed to find out environmentally susceptible areas. Detailed Bathymetric modelling was done using appropriate cartographic techniques and also by constructing 3D models using Computer techniques. Water Samples were collected from different parts of the area and Water Quality Analysis were carried out. Detailed Socio-economic Survey was carried out to ascertain the inhabitants’ quality of living and their suggestions for improvement. The study suggested the need for the improvement of infrastructure and communication facilities for the harbour development and for this the houses at the beach and along the roads have to be resettled for widening the roads. Bathymetric change for the period 1986 to 1995, both in terms of area and volume, revealed a considerable amount of accretion Northeast of the promontory. This accretion is observed after the construction of breakwater. For an efficient sewage disposal system it is suggested to construct a main channel, parallel to the beach in between the present shoreline and the habitated area, to which all sewers can be connected. A wastewater treatment plant was proposed to be constructed behind the promontory and the sewage after treatment can be drained to the sea or can be used for watering the plants in recreational area. It is also suggested to construct two vermi composting plants to treat the solid waste generated from the households and also from the fishing activity, so that the wastes do not enter the harbour basin. There is high demand of sanitation facilities as the water quality analysis revealed high contamination of faecal coliform. Other associated amenities and services like safe drinking water, dispensary etc., were also suggested. Awareness programmes were suggested to involve the active participation of local community.