Environmental impact assessment report harbour development works at Rashdhoo, Alifu Alifu Atoll

Abstract

This Environmental Impact Assessment (EIA) report is to fulfill the regulatory requirements under the Environmental Protection and Preservation Act of Maldives prior to the proposed harbor development at Rashdhoo in Alifu Alifu Atoll. Rashdhoo harbor concept design was formulated after meeting by MHTE, president of Maldives and the island community during the visit by president to Rashdhoo. Large natural deep lagoon and entrances are located at the northern quadrant of the island, which is used by the island community as the main access point to the island. The proposed project involves construction of a 228.6m by 78.7m harbor facility at the northern side of the island, located west of the old jetty head. L shaped concrete elements (precast) will be used for the quay wall structure; and armored rocks will be used for the break waters. The harbor development will be funded by the government of Maldives under the Access Improvement Programme implemented by the Ministry of Housing, Transport and Environment (MHTE). The harbor design incorporates the new harbor design concept (third generation harbor), which includes separate loading and unloading area constructed as a T jetty. Part of the basin will include existing deep lagoon area (eastern side of harbor) the rest will be located on shallow lagoon flat. Sediment excavated to deepen the harbor basin would be disposed at either side of the harbor and back of the harbor (backfilling of the quay wall). The estimated volume of dredged sediment is sufficient for filling either side of the harbor and behind the quay wall only. This report provides the results of the fieldwork carried out on Rashdhoo in September 2009 and January 2010 and associated public and community consultations that followed. The environmental impacts arising from the proposed developments are predicted based on the findings of the fieldwork along with the activities that cause these impacts during the construction and operational phases. Existing environment was examined to identify significant environmental components that would be affected and to establish a baseline condition of the site. Available and relevant literature on environmental impacts associated with similar projects was evaluated to identify possible impacts. Oceanographic data and information on local hydrodynamics were qualitatively assessed to determine the current pattern around the island which was based on monsoonal wind patterns, wind generated waves, tidal flushing, geographic setting, the topography of the lagoon and shape of the shoreline. Three sites were selected to assess reef benthos and selected fish community as the baseline data which would also be considered for long-term monitoring program to monitor the impact of the project. In addition to the fish and benthic surveys, seawater quality was assessed in the lagoon at the north western side of the island (proposed harbor area). The substrate of the lagoon is mostly abiotic. The area to be dredged is dominated with sand and rubble. It is important to note that the most significant impact associated with the project would be impact on the marine environment from sedimentation. Dredging and excavation often carry a heavy load of sediments increasing sediment load in the water column causing discoloration due to suspended sediments of the impact area for a prolonged period. However, there is no established coral community that would be directly affected except perhaps a few isolated coral colonies in the lagoon area. Indirect impact area has high cover of live coral. Environmental impacts associated with the proposed project are considered moderate to major. The significant environmental components that are likely to be affected are the coral community established on the reef flat and changes to littoral drift and near-shore coastal hydrodynamics. Impact on the coral community from sedimentation as a result of excavation is inevitable. Mitigation measures are provided in the report for impacts that were categorized moderate to major. Impact mitigation measures and monitoring is carried out to compare predicted and actual impacts occurring from project activities to determine the efficiency of the mitigation measures. The environmental monitoring proposed here is to determine the effectiveness of the mitigation measures and long term change to the benthic community, especially coral community, where the baseline information was collected. The participants of the consultation meeting held at Rashdhoo stressed the need for mitigation the severe erosion problem at the western side of the island. With due consideration to main environmental components identified and the magnitude of impacts on these components from the proposed developments, the consultant concludes that the project components and designs are feasible and appropriate mitigation measures are given to correct and minimize unfavorable environmental consequences. Furthermore, the public and community consultation responses were in favor of the project due to the socio-economic benefits foreseen to the community from the harbor.