|Abstract: ||This report discusses the findings of an environmental impact study under the shore protection
project proposed for Hoarafushi in Haa Alifu Atoll. The project is proposed by Ministry of
Environment and Energy.
The project comprises of the protection of the eroding area on either sides of the harbour. A
570m long rock boulder revetment on the northwest of the harbour and 230m breakwater on
the southeast of the harbour has been proposed. The project also involves backfill of the
proposed revetment areas using an estimated total of 17,000cbm of sand. The sand is
proposed to be taken from the lagoon on the north of Hoarafushi. The project will be
undertaken as part of the ongoing harbour project and is estimated to take about 180 days with
a manpower requirement estimated at 27 and involving heavy machinery including excavator,
dump truck, loader and crane.
A number of alternatives to the proposed project components have been identified in this
document. Of these, the preferred alternative is a groyne field with a smaller revetment
adjoining the harbour. The cost of the preferred alternative is similar or slightly less but
provides beach in these areas and better protection to downdrift locations, if the structures are
designed properly. Other alternatives include a groyne field with a semi-submerged
breakwater or just a groyne field or a semi-submerged breakwater only. Rock boulders is the
preferred material for the proposed shore protection while geotextile bags or geotextile tubes
may be used as a cheaper alternative but would not be as effective as rock boulders.
Sand is available from the large span of lagoon on the north of Hoarafushi including the three
options considered by the Contractor. The shallow channel between Ungulufinolhu on the
south and Hoarafushi is also an alternative that will help to minimize the magnitude of flow
between these two islands since Kudafinolhu on the northwest of Hoarafushi is now naturally
connected with Hoarafushi. Even when the island on the north was not connected with
Hoarafushi, there was severe erosion on the south of Hoarafushi, as identified in the EIA
report. Therefore, deepening this channel would help to ease the erosion on the southern end
of Hoarafushi. This area is more feasible for the fill behind the proposed revetment on the
south of the harbour. The harbour is also an option, however, may not have material suitable
for beach fill.
Environmental impacts were assessed for both the construction and operational phases of the
project. Most of the direct, negative environmental impacts identified for the construction
phase of the project were minor negative; the main impact being sedimentation during the
filling of the proposed fill areas. However, these impacts are of low significance while the
benefits of the proposed project outweigh the negative impacts including the protection to the
area, which has been eroded mainly as a result of constructing the harbour. In fact, these shore
protection measures should have been proposed as mitigation measures within the EIA for the
harbour project. However, the measures could have been avoided at that time due to
Since there are a few impacts, there are no specific mitigation measures for the proposed
project except to keep the borrow areas at least 50m from shore, as per the requirements of the
Dredging and Reclamation Regulation. However, in order to mitigate the impacts on the
aesthetics of the beach area due to the revetment, it is recommended to minimize the
revetment and consider groyne field or offshore structure as proposed in the alternatives.
However, the proposed revetments may provide better protection to the areas under
consideration. Therefore, it is a choice that the Proponent can make in consultation with the
Engineers and other stakeholders.
General mitigation measures, involving appropriate construction management such as
working during low-tide as much as possible and rigorous supervision during project
implementation are recommended.
Since monitoring has not been undertaken in the past for the harbour project, it is
recommended to carry out monitoring for this project. This project has linkages with the
harbour project and therefore the recommended mitigation measures and monitoring
programmes in the EIA for the harbour project shall be undertaken in conjunction with the
proposed shore protection project. Therefore, a holistic monitoring programme has been
recommended for the eastern shoreline of the island under this project.
In conclusion, it appears justified, from a technical and environmental point of view, to carry
out the proposed shore protection project. Since alternatives have not been considered or
discussed with the relevant stakeholders including the Council, it is recommended to consider
all potential alternatives to shore protection, including those identified by the EIA
Consultants, before proceeding with the project.|