Environmental impact assessment for redevelopment of harbour at Meemu Atoll Dhiggaru

Abstract

This report discusses the findings of the environmental impact study undertaken by MEECO Pvt. Ltd. at the request of the Ministry of Housing and Infrastructure to redevelop the harbour of Meemu atoll Dhiggaru. This EIA report is prepared in accordance with Environmental Impact Assessment Regulations, 2007 under the Environmental Protection and Preservation Act (Act No. 4/93). The purpose of this EIA is to fulfill the requirement of the Law and to conduct an assessment of possible impacts on ecological, biophysical environment and socioeconomics arising from the proposed reconstruction. The main rationale of this project is to increase the safety, accessibility of the current harbor. This project is particularly important as the islands economy mainly depends on fisheries sector. With the current increasing demand of the fishing vessels and the growing sizes of the vessels, an extension of the harbor is needed. This will also enable more job opportunities in Dhiggaru where unemployment rate is high. The existing landside quay wall was constructed to shore extent of the island at the time of construction. However, the quay wall was not extended with the recent reclamation and addition of land. Therefore the reclaimed shore was left as rocks and rubbles. With time, this has become unusable and become difficult for mooring the vessels. To keep pace with the growing demands for the use of the harbor, it became necessary to reconstruct the harbor covering this area. The project involves redevelopment of the exiting harbour in order to facilitate and improve the facilities provided by the harbour. The exiting quay wall on landside would be extended to a have a total length of 268m and the width of the harbour would be extended to 86m. A maintenance dredging would also be carried to a depth of 3m below MSL. In addition, the project also involves relocation of the southern breakwater to further south extending the width and raising of the breakwater heights to 2m above MSL. Breakwater of total length of 449m would also be constructed. The existing entrance channel with a width of 25m would also undergo a maintenance dredging and would be extended in length. It is estimated that approximately 15,500m3 of sand would be dredged from the basin. The dredged material would be used to reclaim the land northwest of the harbor and some of the material would be used in the graveyard. Key impacts The impacts of the project result mainly during construction from activities such as maintenance dredging and reclamation of the land on the North West. Sedimentation and increase in turbidity can impact the marine environment. The reclamation can change the hydrodynamics of the island and will take some to come to equilibrium although this will address the issue of coastal erosion in that area. Baseline environmental conditions at the project site indicated that the live coral cover was almost zero and fish count is very less, showing minimum impact on marine habitat. Indirect impact may also occur from silting which is a short term impact. However, the major socioeconomic impact is found to be positive. Easing the access and creating space for more vessels will facilitate the local users of the harbor and enable development of harbor dependent sectors and livelihood of the residents of M.Dhiggaru. Key negative impacts of the project are found to be significant in short term. These negative environmental impacts weighed against socio-economic positive impacts acts as a justification for the project. Mitigation measures Mitigation measures were taken by conducting appropriate field surveys and environmental assessment of the island, proposed and alternative locations for development of the harbor. The excavation would be carried out during the high tides to allow maximum flushing of the sediments. Reclamation would be done during low tides to minimize the erosion and washing away of the material. The necessary announcements and proper use of sign boards will be used to minimize the difficulties caused during the construction works. Alternate locations and technology The proposed location where the dredged material would be used is the best location as it is the most needed location to be reclaimed for future plans of the island. Alternative technology are not recommended either due to expensive process or the available technology not suitable to the environmental conditions. An environmental management plan with environmental monitoring was developed taking into consideration the impacts and mitigation measures to be implemented. The important elements that require checks such as sediment dynamics, coral cover, shoreline changes, water quality and hydrodynamics will be monitored according to the developed monitoring program during construction and operation period. Although the project involves inevitable negative environmental impacts, such impacts are not serve as to not undertake the project. Mitigation measures have been proposed to adequately minimize the significant impacts. Hence, the project is justifiable in light of the socioeconomic conditions and anticipated benefits from the project which clearly outweigh the negative environmental impacts.