ENVIRONMENTAL STUDIES OF NEENDAKARA FISHING HARBOUR

Funding Agency: Harbour Engineering Department, Government of Kerala

Kerala’s coastal zone is an area of intensive developmental activity due to its unique geographic and economic disposition. The coastal belt of Kerala State is thickly populated and even some of the major towns of the State are located adjacent to the coastal belt. This along with a number of developmental projects; located along the coastal zone have been increasing the environmental stress of the coastal ecosystem heavily. Most of the fishermen population of the State are completely dependent on these coastal zones for their livelihood and the State Government has been implementing a number of developmental programs to increase the marine fish production. ‘Neendakara Harbour’ is situated at the estuary of Ashtamudi Lake which is fed by the river Kallada in Kollam district. It is one of the major fishing centres in Kerala. This study envisaged to analyse the various environmental impacts of Neendakara Fishing Harbour and to formulate an Environmental Management Plan for the area. There are also the problems of both water pollution and pollution due to the solid waste generated during the various operations of the fishing harbour. The detailed objectives of the project were to study the natural determinants of environment, to study the impact of Harbour construction on sedimentation pattern and to study accretion of various regions of harbour area through the analysis of bathymetric data, to asses the quality of water and to identify pollution prone areas, to conduct a detailed socio economic survey and to suggest an Environmental Management Plan for the Harbour area.

Detailed Resource Mapping was carried out in the Cadastral level and Information on various environmental factors was collected during the field study. The sewage network of the area was mapped. Different thematic maps on Landuse, Geomorphology, Assets and Water quality were prepared. Three bathymetric maps of Neendakara harbour were analysed using GIS to study annual and pre-monsoon sediment dynamics. To find out the temporal dynamics of the bottom configuration two overlays were prepared. These data were analysed both by using Cartographic Techniques and by generating Computer models to study the trend of sediment movements.

The analysis brought out a prominent accretion zone in the southern extension of the northern breakwater. It also showed that there is considerable accumulation of sediment on the eastern half of the quay. As a result of dredging been temporarily stopped, the sand bar was gradually spreading and only half the length of wharf is effectively useful for launching and landing of boats. The sand bar developed has an east-west orientation parallel to the estuary mouth. Enormous amount of sediment brought by the Kallada River coupled with the pressure of seawater, drive the sediments to the quay. Being a protected body of water and with very limited natural flushing possibilities, whatever the quantity of sediment brought in gets trapped in. With the development of the sand bar the natural movement of the water is further restricted. Moreover the huge amount of fish waste sorted near the quay and the sewage from the surrounding area are disposed within the basin itself. The drainage channels were constructed without giving much consideration to the slope characteristics of land and the tidal pattern. The sewage and solid waste management practices were highly inefficient and unhygienic. The study suggested separate treatment plants for sewer and solid waste. The fish waste together with other solid waste was suggested to treat either by composting or biomethanation. Proper and scientific desilting methods were necessary to keep the depth of the basin ideal for the movement of the boats. The marshy land was suggested to plant with suitable mangrove species, which may help restore the coastal ecosystem and give an aesthetic view. Proper sanitation facilities, dispensary, safe drinking water and other basic amenities were also suggested.