EVALUATION OF THE IMPACTS OF HARBOUR ENGINEERING IN ANIBARE BAY, REPUBLIC OF NAURU

摘要

This paper presents the evaluation of impacts of harbour engineering in Anibare Bay,rnRepublic of Nauru. The bay and beach is of carbonate sand and gravel, behind a narrowrnreef and backreef developed on dolomite a substrate. The bay is dynamic and open to thernocean, with active erosion at the development site. The beach is moderately sloping andrnshows sign of current erosion, with fresh scarps. Harbour development has increased thisrnerosion and erosion has exacerbated. Updrift and downdrift erosion has resulted from waverndiffraction around the structure by Easterly modal waves. Structures are frequentlyrnovertopped, with noticeable run-up. Rip-rap specified for construction is too small, whilernbreakwater heights are conservative for the prevailing hydraulic regime, while flanking isrnan immediate problem. Monitoring and post-construction analysis is recommended, whilernmaintenance is needed for already eroded beaches. These will facilitate timely repair torndamaged infrastructure and eroding coasts. It is recommended that future coastalrndevelopments should be preceded by an environmental impact assessment.