Environmental impact assessment for the proposed shore protect in Madaveli, Gaafu Dhaalu Atoll

Abstract

The purpose of this document is to fulfil the requirements to get necessary environmental clearance from the Environmental Protection Agency (EPA) to carry out the proposed shore protection project in Madaveli, Gaafu Dhaalu Atoll. The proponent of this project is Ministry of Environment & Energy (MoE). The main rationale of the project is to mitigate coastal flooding on the northern side of Madaveli Island. The houses within close proximity to the wetland has been subject to seasonal coastal flooding and associated personal property damage. The project activities is expected to protect the affected houses from future damage. The project mainly involves construction of approximately 350 m long rock boulder revetment on the NE corner of Madaveli Island, and backfilling an area of 10,000 sq. m behind the revetment by dredging 25,000 cbm of sand from the island lagoon. The development is designed based on environmental best practices suitable for marine construction in Maldives. It is anticipated that the completion of the whole project will take approximately 4 to 5 months. Madaveli is an inhabited island and has been experiencing coastal flooding on its northern end due to low elevation and settlement expansion into flood risk zones. The area is question is a low lying tidal flat covering at least 20% of the island. The environmental concerns relating to this project also centres around the tidal flat. The area does not appear to have much of a floral uniqueness as most of the vegetation contains Kuredhi and the usual mangrove vegetation associated with such inter-tidal zones are absent. The ecology in the area is in good condition but is subject to preservation of inter-tidal conditions. The proposed concept master plan has gone through iterations based on consultations with the public, proponent and contractor. The original design proposed a 450 m long revetment blocking the entire northern tidal flat area. The long-term vision of the locals to were to one day undertake reclamation in the areas. It was recommended not close the inter-tidal zone without a proper plan and funding to develop the area. The EIA consultants with endorsement from EPA during consultations proposed a partial revetment and partial breakwater, that would allow for tidal flushing. The public (as informed by Island Council) agreed but discussion between MoE and Contractor deemed the option to be beyond the budget. A compromised solution was reached between MoE and contractor to leave one opening. The present plan reflects this solution. However, further assessment reveals that the opening may allow waves to come through the opening due to its positioning. An alternative option to put a breakwater to prevent direct approach of waves has been proposed, if project budget can accommodate it. All project activities are in conformance to the laws and regulations of the Maldives, and relevant international conventions that Maldives is party to. The key laws and regulations applicable to this project are: Environmental Protection and Preservation Act, Dredging and Reclamation regulation and Environmental Impact Assessment Regulation 2012. Additional approvals are required before commencement of the project including detailed contractor drawings approval from the Ministry of Environment, and dredging and reclamation approval. The assessment shows that the proposed developments involve significant positive and negative impacts on the marine, coastal, terrestrial and social environment. The main impacts on the marine environment are from dredging and reclamation and resulting turbidity and sedimentation. Areas close to the dredging and reclamation site will be severely affected, in particular the seagrass bed and live coral colonies immediately east of the dredging site. The borrow site is expected to flush regularly but a cross-bund that restricts from west to east will reduce this process. The project will alter hydrodynamics on the northern side but is unlikely to affect the coastal processes to the extent that it may cause erosion elsewhere on the island. There may be significant impacts if the tidal flat if the area is to be closed. Reduction in flow will alter the habitats and may lead to stagnation. The constant contact of solid waste with an enclosed area may result in rapid water quality degradation, discoloration and smell. In the longrun, the area may become a nuisance to the public than the benefits of large shore protection structure may be able to provide. The opening proposed in the current design will keep the water flowing but it will still alter the overall condition of the tidal flat area. The project has major beneficial impacts on the public, particularly in relation to flooding risk reduction. The fact that the project is being undertaken with other marine works projects reduces the temporal impacts on marine life compared to multiple marine works being undertaken consequentially or over multiple years. Key mitigation measures for the construction stage include working during calm conditions, completing the works in the shortest time period possible, and informing stakeholders at all stages of the project to reduce social conflicts. It has also been recommended to construct drains in all areas where new reclamation is adjacent to the beach areas, particularly on the northeastern half of the island. Consultations were undertaken with Madaveli Island Council, public of Madaveli, Ministry of Housing and Infrastructure and Ministry of Environment. The island council and majority of the island public were strongly in favour of the original master plan that involved blocking the wetland area. They expressed hope that this would lead to reclamation of the wetland in the near future to create the much needed land area for immediate social needs such as housing. However after a thorough an iterative process of consultation between MEE, EIA consultant, EPA and Island council, the master plan concept of the project was further refined and it was decided that blocking the wetland was not justified since there were no plans to manage the environmental impacts associated with change in flushing in the wetland. The alternatives evaluated for the project were the no project option, alternative flood mitigation plan for the north side, and alternative borrow sites. The "no project" option is not viable due to the scale of impacts of flooding felt on northern side houses and public infrastructure and the urgency to mitigate these impacts. Four options have been evaluated in this report to mitigate flooding in the northern side; (1) A revetment across the entire length of northern shoreline (2) A part breakwater - part revetment along the northern shoreline (3) Partial revetment and beach replenishment along the northern shoreline, and (4) Alternative to the final layout which includes construction of an extra breakwater unit. Option 2 has been preferred on environmental grounds but was deemed beyond the budget during consultations between MoE and Contractor. The present concept plan reflects the compromised solution between MoE and contractor. Consultations on the new designs was conducted by MoE and Island Council and the Council has approved the new design. The proposed site plan has been necessitated over the other solutions based on budgetary limitations. However, if budget permits, it is recommended to consider option 4 to complement current design. The monitoring plan has been designed with a focus to analyse the significant impacts over time, particularly the effect on water quality and the impacts on marine life A management framework has been proposed and it is essential that this framework be used in the construction stage of the project. The operation stage management can fall within the overall environmental management framework. Given the importance of this project to the local community, it is recommended to proceed with the project with the mitigation measures and alternatives proposed in the EIA. It is imperative that works beyond those evaluated in this EIA not be undertaken on the northern side, particularly in relation to the opening created for tidal flushing.