Environmental impact assessment for the proposed water supply system in HA. Dhihdhoo

Abstract

The purpose of this document is to fulfil the requirements to get necessary environmental clearance from the Environmental Protection Agency to establish the proposed Water Supply System at Dhidhdhoo, Haa Alifu Atoll. The proponent of this project is Ministry of Environment and Energy (MEE). Project contractor is Sierra Construction Private Limited. The main rationale for the project is to enhance the quality of services and quality of life of residents of Ha.Dhidhdhoo by establishing a proper potable water supply system that will provide clean and safe water for the residents of Ha.Dhidhdhoo. The project is intended at providing an integrated water supply system covering rainwater and desalinated water production and supply. The project is expected to be completed in 12 months. The proposed project involves installation and establishment of two 220 cbm/day reverse osmosis plant systems, construction of two boreholes to supply water for the RO plants, construction of RO plant building, construction of water storage tanks, construction of brine discharge outfall, preparation of catchment areas, establishment of water treatment systems, laying of pipe networks for water distribution and rainwater collection, and household connections. Currently the main sources of water in the island are shallow wells constructed in individual households or in public areas (e.g. a mosque). This is supplemented by collection of rainwater. These methods provide inadequate quantity and unacceptable quality due to the over abstraction, pollution from past sewage disposal system of septic tanks and the unreliability of rainwater harvesting. A reverse osmosis desalination plant of capacity 10 ton is in operation, but the production capacity of this plant is not sufficient to meet the public water demand. All project activities will be 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, Environmental Impact Assessment Regulation 2012, Desalination Systems Regulations, and Waste Management Regulation 2013. The proposed site is located on the northern side of the island just within the old vegetation line. The site is comprised of beach vegetation mainly and has not been used in the past for any purpose. No trees of significant importance are required to be removed for this project. Marine surveys conducted at the proposed brine outfall location showed that the area is made up of mainly dead corals with sparsely distributed juvenile coral patches. No major live coral colonies were observed within this area. Current flow on the northeast corner, where brine outfall is proposed to be located, is expected to be high for most part of the year. The assessment shows that the RO systems can be developed on the island with limited implications on the environment. The assessment shows that the proposed developments involve significant impacts on the marine environment and terrestrial environment due to brine outfall construction, brine discharge, ground excavation and operation of vehicles and machinery. The project also involves moderately significant health and safety risks due to equipment handling and pollution. However, the predicted impacts can be minimized considerably with the proposed mitigation measures. Significant impacts of operation stage include marine degradation due to brine discharge ,increased GHG emissions due to RO plant and operation of pumps stations, and increased cost of living due to additional cost in purchasing water. The assessment shows that the proposed project has many positive impacts including improved quality and accessibility to potable water, protection of groundwater aquifer, reduction of water related disaster risk, and increased employment and business opportunities The alternatives evaluated for the project are „No Project‟ alternative and alternative brine outfall locations. The “No Project” option is not deemed preferable, given the disadvantages of existing situation of potable water in the island. An alternative site was explored as brine outfall locations, by reducing the length of the outfall. Due to better flushing, the proposed longer option was preferred. Monitoring plan is designed to assess any changes to the coral reef environment of the island, terrestrial environment, the ground and marine water quality, as these are the key areas that will be impacted from this project. The management plan for this project is designed to produce a framework for anticipated impacts, including practicable and achievable performance requirements and systems for monitoring, reporting and implementing corrective actions. In addition provide evidence of compliance to legislation, policies, guidelines and requirements of relevant authorities. Stakeholder consultations for this EIA were conducted with Didhdhoo Island Council, Dhidhdhoo FENAKA Office, public of Dhidhdhoo, and Health Protection Agency (HPA). In general, all stakeholders consulted were supportive of the proposed project. In conclusion, this project has been designed in conformance to the relevant laws and regulations of Maldives. The most significant impacts are expected to be short-term impacts for the construction phase. Operational stage impacts are mainly limited to brine out fall location and emission due to power generation. However, mitigation measures have been proposed to adequately minimise these significant impacts.