Environmental impact assessment L. Hithadhoo harbour rehabilitation project

Abstract

This report discusses the findings of an environmental impact study undertaken by Water Solutions Pvt. Ltd. at the request of Ministry of Housing and Infrastructure for the proposed harbour rehabilitation project at L. Hithadhoo. L. Hithadhoo is located southern side of Laamu Atoll. The island economy depends mainly on fisheries which involve boating activities. The existing harbour at the island was constructed in early 2000s. The quay wall was constructed using corals and is badly damaged. The harbour does not have a breakwater and this is causing difficulty to moore the boats in the harbour area during rough weather. The harbour has become too small to cater the large and deep draft vessels which call to the harbour. Hence the proposed project is to rehabilitee the existing harbour which can cater the growing demand for the vessels which will be using the islands for the next 10 years. The rehabilitation of the harbour includes, construction of 229 m of quay on southern side, 90 m of quay wall on eastern side and 88 m quay wall on western side of the harbour. The project also includes construction of 219m breakwater on northern side, 26 m and 24 m breakwater on either side of the entrance channel and 14 m rock boulders revetment on eastern and western side of the harbour. As part of the project, harbour basin would be deepen to – 3 at mean sea level. The harbour basin would be made 227 m long and 88 m wide. The rehabilitation of the harbour basin would generate around 23,0257 m3 sand. This material would be disposed to the area east and west of the harbour. The reclamation would require 36,019 m3 sand. Additional materials required for the reclamation would be borrowed from the borrow site on east of the existing harbour area.. Environmental impacts of the project were assessed. The impacts of the project result mainly from excavation of the harbour basin, entrance channel, excavation of the area on land to shift the quay wall by 50ft inland and disposal of excavated materials. The impact of excavation would be that of sedimentation. This impact is considered to be minor and shortterm. Re-excavation of the entrance channel and harbour basin would have irreversible impacts. The socio-economic benefits of the project may be considered to outweigh the negative impacts of the project on the physical environment of the island especially increasing the usable space on the quay wall, mooring area at the island’s harbour and additional land that would be available to develop fish processing industry. The proposed project conforms to prevalent environmental legislation and thrives to achieve its objectives in an environmentally friendly manner. Mitigation measures for these anticipated impacts have been identified and outlined in detail, including sedimentation and stagnation control methods and measures for minimizing negative effects demolition of the quay wall and the generation of construction waste. These mitigation measures need to be followed in order to minimize environmental damage. The details of the project have been established after considering the needs and requirements of the community by assessing and incorporating the outcomes from the community consultations held during the data collection stage. The EIA also allowed to explore the possible alternatives for the proposed development and identified key mitigation strategies. Alternative locations and alternative designs have been investigated for the different components of the project. However, the present project design seems to be a feasible option in terms of costs, durability and safety. An environmental management plan with environmental monitoring plan has been developed including important elements that require regular checks. This monitoring component will be adhered to and will allow the assessment of changes due to construction of the harbour. Although the project involves inevitable negative environmental impacts, such impacts are not severe as to not undertake the project. The project is justifiable in light of the socioeconomic conditions and anticipated benefits resulting from the project, which seem to outweigh the negative environmental impacts.