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Technical Report
Environmental impact assessment for the proposed development of an agricultural island Dhurureha Thaa Atoll, Maldives
(2017-09) Sandcays
This report discusses the findings of a social and environmental impact study under the proposed development of agriculture on Dhururehaa, Thaa Atoll. The project is proposed by Mohamed Latheef. The proponent aims at developing Dhurureha as an agricultural island; providing job opportunities, reducing dependency on imported produce and ultimately working towards economic diversification and growth of Maldivian economy. The agricultural activities on Dhurureha will be carried out in greenhouses as a hydroponics system. A total of 12 greenhouses (100ft by 50ft each) is proposed to be built for growing tomato, capsicum, bell pepper and lettuce. Additionally, a 60m by 30m nursery will be built on the island. Access to the island is to be provided by dredging an access channel and a 200m jetty. Water requirement for the project is to be met by utilizing an RO plant. A suitable size diesel generator will be used throughout the project to meet power requirement. Staff facilities such as accommodation, mesh room, mosque and office building will also be constructed on the island. A cold storage, general storage and small packaging facility will also be constructed on the island during construction stage. A waste collection and management station will be established for using during construction phase and operational phase of the project At present, Dhurureha is an uninhabited island not used for any purpose. However, locals of the nearby communities use the island to collect coconuts, go on picnics and gather firewood. Alternatives to project components have been identified in the project document. These include alternative uses of the island such as for a tourist resort. However, upon closer analysis of these options, the proposed development of the island for agricultural purpose was found to be more viable based on the present circumstances under which the island has been leased. Therefore, the consultants propose exploring use of alternative renewable sources to the proposed fuel based energy generation. Environmental impacts were assessed for both the construction and operation phase of the project. Most of the environmental impacts of the project have been identified as minor negative with highly positive socio-economic impacts. The main negative impacts from the project include habitat loss from vegetation clearance, sedimentation and consequent impacts on marine wildlife health and waste generation during the operational phase. The mitigation measures outlined for these impacts include conserving mature trees to the greatest possible extent, relocating large live corals at the proposed access channel area and establishing dust control plans in addition to employing best-practice guidelines during the operational phase. The most positive socio-economic impacts related to the project are increase in job opportunities, reduction in prices of agricultural produce and increase of national revenue. It is inevitable that there would be some negative environmental impacts. However, most of the impacts of the proposed project are minor compared to the positive socio-economic benefits of the proposed system. Yet, monitoring to ensure the effectiveness of the proposed project would be necessary. Therefore, a monitoring component has been suggested which takes in to consideration, the most important elements that require regular checks. This monitoring component will be adhered to and will allow the assessment of changes due to construction and implementation of the proposed agriculture project. Monitoring is specifically focussed on employment opportunities, price changes in the market, direct and indirect economic ventures, ground and marine water quality, changes in the hydrodynamics of the project area as well as impacts on the reef or marine ecological area of importance. In conclusion, it appears justified from a technical and environmental point of view, to carry out the proposed project to develop Dhurureha as an agricultural island.
Technical Report
Environmental impact assessment proposed milkfish aquaculture project Matu, Gaafu Alif Atoll
(2017-07) Sandcays
This report addresses the environmental concerns of the proposed milkfish (Chanos chanos) hatchery project in Ga. Matu. The project is proposed by Ministry of Fisheries and Agriculture. Concerns about live-bait availability over prolonged periods are being raised in recent years, especially in the southern atolls of Maldives. The development of aquaculture for selected bait species is seen as one possible measure to manage the live bait shortage currently faced by local fishermen. Cultured milkfish has been in use for the longlining industry in different parts of the world, and successfully piloted for the pole-and-line industry in Indonesia and Kiribati. Unlike most of the live bait species currently in use in the pole-and-line fishery, hatchery technology is well developed for milkfish. In addition, the relatively short duration to reach bait-size makes milkfish an ideal species for aquaculture development. Supplementing the tuna fishermen with cultured bait is expected to reduce the time spent on bait search, and in turn, result in increased effort directed to the tuna fishery. As live bait shortage is mostly reported from the southern atolls, the proposed hatchery site was selected from Gaafu Alif atoll, for logistical ease in distribution for the most needed areas can be made. The selected island, Matu from Ga. Atoll is 5.9 Ha small uninhabited island on the northern side of Ga.Atoll. The closest inhabited islands to the project site are Ga. Villingili and Kolamaafushi. The project aims to produce 100 tons of milkfish raised to the size of live bait used in the pole-and-line fishery. All required technical and support infrastructure will be constructed during the construction phase of the project. The operational phase will involve water circulation, feeding and rearing of cultured stock. In addition to hatchery, nursery and broodstock modules built on land, sea cages will be built for brood stock. Power will be provided for the project via diesel generators, while potable water will be provided via RO plants. Accommodation for staff and administrative buildings and waste management centre will also be constructed on the island. Access to the island will be provided via access channel and a jetty. The naturally deep lagoon will be used as a harbour during the project. Social and environmental concerns regarding the proposed project include: • Vegetation clearance during site preparation for construction of land infrastructures. This impact is considered minor negative as outmost care will be taken to reduce cutting down mature vegetation. Buildings will be adjusted as much as possible to reduce requirement of cutting or relocation of mature trees. When unavoidable, two plants for every tree cut will be planted on the island. • Sedimentation during excavation of access channel and construction of main jetty. This impact is considered as negligible as the excavation involved is very minor. Measures to reduce this impact such as working during calm weather and low-tide has been suggested as mitigation measures. • Minor impacts due to human activity in the area including littering both during construction and operational phases. • Increased nutrient loadings from faeces and uneaten food wastes, which will either dissolve or settle on the seabed beneath the cage. Since the water is deep and adequate currents exist, eutrophication is, however, unlikely. The proposed project is expected to be managed in conformity with local and international regulations and standards of relevance, especially environmental regulations and standards. Therefore, environmental impacts will be well managed, minimized and mitigated. Given that the project has major socio-economic benefits and some environmental benefits (potential to reduce pressure on wild populations of baitfish), it is recommended to allow the project to proceed as proposed. It is important to consider uncertainties and continue to monitor the project impacts and undertake appropriate mitigation measures in consultation with the EPA and other relevant government agencies. It is also necessary to undertake regular environmental monitoring activities.
Technical Report
Environmental impact assessment for: Hdh. Neykurendhoo channel protection and maintenance dredging project
(2015-12) Maldives Energy and Environmental Company
a) This Environmental Impact Assessment (EIA) report was prepared by Maldives Energy and Environmental Company (MEECO) upon request by the Ministry of Housing and Infrastructure (MHI), the project proponent to fulfil the legal requirements of the Environment Protection and Preservation Act (Law no: 4/93) for the project entitled “HDh. Neykurendhoo channel protection and maintenance dredging”. b) The assessment was prepared addressing the key issues highlighted in the Terms of Reference (TOR) agreed between the proponent and EPA. c) Neykurendhoo is an average sized island with a population of a little over 700, where basic services are available. The island has got an average sized harbour constructed in 2007 that is currently being used by boats owned locally as well as fishing and cargo vessels from other islands as a berthing location. d) MHI proposed this project to address the requirement for providing safe access to Neykurendhoo. No maintenance dredging had been carried out since the construction of the harbour in 2007. The channel is reported to have become shallower over the years as a result of siltation in the area. In addition the breakwater at the entrance of the harbour was constructed too short to provide adequate protection from wind and waves. e) The project is in line with government policies and legislation, and the proponent is committed to obtaining all the necessary permits and approvals prior to the commencement of the project. f) The project proposes to construct a 116.2 m rock boulder extension to the existing breakwater at the entrance channel, and apply excavation techniques to conduct maintenance dredging. The dredge material is proposed to be used for levelling the access road from the residential areas of the island to the harbour. The proponent commits to put in place all the measures necessary to minimise the impacts of the development on the environment. g) Assessment of the existing environment revealed that there were relatively few benthic communities to be directly affected as a result of the proposed activities. The channel has a sandy bottom characteristic of dredged locations. The only activity expected to cause damage to the benthic communities were the placement of the rock boulder extension to the breakwater. However, the coral communities in the area were in relatively sparse abundance and consisted only of small colonies. The impact on coral reefs is expected to revert back to its original state once the environment has stabilised upon completion of the project. h) The major impact to the surrounding areas would be from sedimentation during dredging, especially since for much of the year the location will experience winds and the resulting wind-generated surface currents away from the island. Adequate silt netting would minimise the impacts to the surrounding areas during construction phase. i) The proponent is fully committed to fulfilling the requirements of the monitoring plan developed, and undertake any mitigation measures necessary to minimise the negative impacts of this project j) The benefits of this project outweigh the slight negative impacts caused by the project, and is encouraged to implement the project giving due considerations to the environmental issues.
Technical Report
Environmental impact assessment for the proposed brine discharge line Hulhumalé Industrial Zone Kaafu Atoll, Maldives
(2015-10) Sandcays
This report discusses the findings of an environmental impact study for the construction and operation of the proposed brine discharge line in Industrial Zone of Hulhumalé to allow ENSIS Factory to discharge the brine from their registered desalination plant as well as to provide the same for other industries who may require the service in future. The project involves construction of a pump well with a small dewatering pump that will pump the water from the location of the pump to the discharge location. The brine discharge line from the factory to the pump well would be a gravity line running along the side of the existing roads. The Proponent of this project is Housing Development Corporation (HDC), which has the primary function of providing housing and development infrastructure for Hulhumalé. The objective of the brine discharge line is to facilitate the ENSIS factory’s brine discharge while providing the same opportunity for other factories that may require the service once their desalination plants have been registered. Initially, the charges for the construction and operation of the brine discharge line will be borne by ENSIS Group, which would be compensated for as other factories connect their brine discharge line. An appropriate mechanism would be established. The depth of the pump well will be about 1.5m. Given the high elevation of the reclaimed land of Hulhumalé, only a small degree of dewatering may be required during the construction of the pump well. If required, dewatering will be carried out after necessary approvals under the Dewatering Regulation of the Maldives. The discharge line will run between the ENSIS factory and the quawall at the harbour area, where the brine will be discharged. Section of road will be excavated while a small section of asphalt road would be cut across to make way for the pipes, which will be made good once the pipes are laid. The discharge area is a dredged basin which is open to the Hulhumalé lagoon and at least 500m from the inner reefline on the western side of Hulhumalé. Due to shortage of fresh water supply during early development stage of the Industrial Zone in Hulhumalé, some developers had to install their own desalination plants to cater to their production demand. Similarly, a temporary discharge pipe had to be laid for waste and RO reject water disposal due to absence of sewer network in the area. On top of that, MWSC, the sole water and sewerage service provider for Hulhumalé has indicated to HDC that MWSC may start sewage treatment in 2015 and RO reject water may affect the treatment process. Most of the industries including the ENSIS fish factory needs large volumes of water and for that reason the factory has installed and recently registered their desalination plant with the Environmental Protection Agency. However, the application for the brine discharge line in the industrial zone has been held for over a year pending the resolution of the matter with MWSC. It is crucial that ENSIS factory is allowed to proceed to operate their registered RO plant. Therefore, HDC wishes to provide a separate brine discharge line for ENSIS and other similar industries demanding for the service. The proposed brine discharge line will ease the current difficulties faced by ENSIS and other factories in the industrial area. These industries are responsible for several job opportunities and contribute well to the state revenue and national GDP. ENSIS factory not only contributes to the fishery exports but also to sustainable fisheries and minimizes dependence on imports in a country where almost everything is imported. The impact area is the area to be excavated for the pipeline and the discharge location. The proposed project will have some minor negative impacts on the discharge location. However, the discharge location is the deepened/dredged lagoon, where there is no coral cover of any sort and the nearest housereef is about 500m from the discharge location. Therefore, the impact is of no significance. The impacts within the island will mainly consist of possible small scale and temporal changes to topography from laying out the pipe network and temporary negative effects on groundwater quality (if any). Since there were no significant environmental impacts identified for the proposed project, mitigation measure were general construction phase guidelines such as dust control measures and waste management plans. A monitoring programme has been suggested for at least two years. The monitoring would mainly focus on the water quality at the brine discharge location.
Technical Report
Environmental impact assessment for the proposed resort development Maareha Gaaf Alif Atoll, Maldives
(2014-04) Sandcays
This report addresses the environmental concerns of the proposed development of a resort on Maareha, Gaafu Alifu Atoll. The island is about 16.5hectares in its size and is located on a shared reef system at the eastern side of Gaafu Alifu Atoll. The Proponent of the proposed development is Moving International Pvt. Ltd. The Proponent proposes to develop a modern resort on Maareha with 20-bed Family Villas, 98-bed Water villas, 208-bed Beach Bungalows, 84-bed Beach Twin Villas and 4-bed Presidential Villas. Furthermore, it also includes Arrival Pavillion, Diving school, Medical Clinic, Mosque, Service jetty, Main Restaurant, Souvenir and Jewellery shops, Coffee shop / Bar, Swimming pool, Sports and recreation center for guests, Cinema, AV room, Karoake, Disco, Water Sports Center, Football Ground, Basketball Court, Tennis Court, Spa Complex, Children Play, Recycle House, Staff Recreation Center, Staff Training Center, Cafes and different utilities including desalination plant, sewage treatment plant, waste management center and powerhouse. The proposed development will conform to all current environmental legislation including the Regulation on the Protection and Conservation of the Environment in the Tourism Industry. The main negative impact of the proposed development will be the impact of sedimentation on the areas of the housereef on the west where the proposed harbour and access channel will be developed and the impact of deforestation due to land clearance for proposed buildings. These impacts are inevitable. Yet, every effort is to be made to minimize the impact and footprint of the impact. The impact of sedimentation on the reef will be minimized by taking into consideration appropriate hydrodynamic and tidal conditions, creating settlement basins as the dredging activity proceeds or by using silt screens. To minimize the impact of deforestation, buildings will be designed around mature trees minimizing their removal. If a mature tree were to be removed, they will be carefully uprooted and transplanted elsewhere. The negative impacts of the water villas include impacts on sediment transport around the northwestern side of Maareha and some minor degree of sedimentation on the reef nearby. There will be no impact on neighbouring Medhuhutta, which is about 50m, due to the strong currents in the channel between the two islands (over 0.5m/s) helping them to behave as two separate littoral systems. However, there are uncertainties given the lack of data and hence monitoring hydrodynamics and changes to shoreline of both islands during the construction as well as operational phase will further help to evaluate this impact more accurately. To minimize this impact on longshore sediment transport, the walkways of water villas will stand on piles with their footings buried in the seabed. The impact of sedimentation will be minimized by taking care to move the water villas as far away from the live reef areas as possible and transplanting any live corals that may be directly impacted. Care will also be taken to minimize sedimentation on the reef when placing water villa footings and columns. Precast footings and columns will be used and excavator movements shall be minimized. Excavator is preferably moved on barge to minimize sedimentation and if high bed excavators were to be used, they shall move as far from coral reef flat areas as possible. This impact of sedimentation will be short-lived given that tidal and wind-driven currents would normally carry the sediments away from the reef at all tides and monsoons. It is vital, therefore, to monitor the condition of the reef prior to the start of works, during the works and after the works to establish the true nature of the impact. The other environmental impacts of the proposed development include solid waste management, water supply, sewage disposal and energy generation. Solid waste will be generated both during the constructional and operational phase of the resort. Constructional waste will be disposed of by the Contractor to Thilafushi if a regional landfill or waste management site does not exist. During the operational phase, a waste management center established on the island will segregate waste and dispose of them in a manner prescribed in tourism regulations. It is during the construction stage that the waste is often not managed properly and waste ends up in the environment. Therefore, it is vital that waste management procedures are in place during construction phase to ensure waste is appropriately dealt with. Supervision and awareness of construction workforce is highly recommended. Desalination, sewage treatment and power generation are fuel-dependent processes and fuel efficient desalination technology, STPs and, especially, generator sets will be installed in the island. Solar water heaters have been proposed and photovoltaic system incorporated, the costs of which have already been taken into consideration. Gravity sewers will deliver the sewage and only a single pumping station will be used. Treated effluent with low levels of BOD (less than 20mg/l) will be disposed to the sea at not less than 10m below MSL and 5m away from the reef edge. Therefore, the impact from sewage disposal will be almost negligible. In fact, the daily peak flows is quite small that the proposed sea outfall would provide over 500-fold dilution to the sewage effluent even if it were raw sewage, which would occur only in the unlikely event that the sewage treatment plant fails. Hence, no further mitigation measures have been considered for sewage disposal and treatment. The project encompasses clean technology and an initial investment worth a million dollars would be spent on solar energy system. This will complement the proposed diesel generator sets. In addition, solar water heaters will be installed to provide hot water to all guest units. Also, to minimize fuel and water consumption, it is proposed to install energy and water efficient technology including faucets. The costs of these have already been included in the project. Environmental monitoring has also been incorporated into the project. Arrangements for monitoring during constructional and operational phase will be considered immediately upon EIA approval. Monitoring will be undertaken according to the monitoring programme recommended in this report. Recommended monitoring for the project includes the monitoring of shoreline at predetermined and bench-marked tide level, beach profiles and drogues at locations given in the EIA report, marine water quality at the location of the intake, brine discharge, sea outfall and a control location, groundwater at a location close to the powerhouse and desalination plant and a control location and quality of product water at 3 specified locations including product water tank. Annual monitoring reports have to be submitted to the Environmental Protection Agency over the monitoring period and shall include fuel and water consumption data and greenhouse gas emission calculations. The overall environmental impacts of the project have been assessed using appropriate matrices and the results indicated that the proposed project has net positive impact. Given that the project has major socio-economic benefits although there would be some negative environmental impacts, it is recommended to allow the project to proceed as proposed.
Technical Report
Environmental impact assessment for the proposed resort development Kandinma Dhaalu Atoll, Maldives
(2014-07) Sandcays
This report addresses the environmental concerns of the proposed development of a resort on Kandinma, Dhaal Atoll. The island is about 36.9hectares in its size. The Proponent of the proposed development is Reollo Investments Pvt. Ltd. The Proponent proposes to develop a modern resort on Kandinma with 220 Beach Villas and 70 Water Villas. With restaurants, bars, spa, reception, guest shop, pool, gym, staff accommodation, staff facilities and different utilities including desalination plant, sewage treatment plant, waste management center and powerhouse, the resort is an independent economic unit. It has one jetty for guest arrival and a small harbour for use by service vessels. The island lacks beach, which is an essential component of a beach resort, therefore, beaches on the west side would be nourished using sand dredged from the channel and harbour along with sand extracted from edges of the deep lagoon. The proposed development will conform to all current environmental legislation including the Regulation on the Protection and Conservation of the Environment in the Tourism Industry. The main negative impact of the proposed development will be the impact of sedimentation on the areas of the housereef on the west where the proposed harbour and access channel will be developed and the impact of deforestation due to land clearance for proposed buildings. These impacts are inevitable. Yet, every effort is to be made to minimize the impact and footprint of the impact. As such mature trees will be further taken into consideration during the construction phase by adjusting buildings during stakeout. If a mature tree were to be removed, they will be carefully uprooted and transplanted elsewhere. The impact of sedimentation on the reef will be minimized by taking into consideration appropriate hydrodynamic and tidal conditions as the dredging activity proceeds. To minimize the impact on longshore sediment transport, the walkways of water villas and jetties will stand on piles with their footings buried in the seabed. Precast footings and columns will be used and excavator movements shall be minimized. Excavator is preferably moved on barge to minimize sedimentation and if high bed excavators were to be used, they will not be driven on areas with coral since no structures have been placed in areas with live coral or significant coral cover. Furthermore, sedimentation will be short-lived given that tidal and wind-driven currents would normally carry the sediments away from the reef at all tides and monsoons. The other environmental impacts of the proposed development include solid waste management, water supply, sewage disposal and energy generation. Solid waste will be generated both during the constructional and operational phase of the resort. Constructional waste will be disposed of by the Contractor to Thilafushi if a regional landfill or waste management site does not exist. During the operational phase, a waste management center established on the island will segregate waste and dispose of them in a manner prescribed in Tourism Regulations as well as the Solid Waste Management Regulations. It is during the construction stage that the waste is often not managed properly and waste ends up in the environment. Therefore, it is vital that waste management procedures are in place during construction phase to ensure waste is appropriately dealt with. Supervision and awareness of construction workforce is highly recommended. Desalination, sewage treatment and power generation are fuel-dependent processes and fuel efficient desalination technology, STPs and, especially, generator sets will be installed in the island. Gravity sewers will deliver the sewage and only a single pumping station will be used. Treated effluent with acceptable levels of BOD will be disposed to the sea at not less than 10m below MSL and 5m away from the reef edge. Therefore, the impact from sewage disposal will be almost negligible. In fact, the daily peak flows is quite small that the proposed sea outfall would provide over 500-fold dilution to the sewage effluent even if it were raw sewage, which would occur only in the unlikely event that the sewage treatment plant fails. Hence, no further mitigation measures have been considered for sewage disposal and treatment. Furthermore, the sewage treatment plant, being an energy-intense process, may be avoided given that the outfall can be located in a location where there is good mixing and a great degree of dilution and not used by tourists or locals. However, sewage treatment in tourist resorts is a legal requirement without any provisions in the Tourism Regulations. Environmental monitoring has also been incorporated into the project. Arrangements for monitoring during constructional and operational phase will be considered. Monitoring will be undertaken according to the monitoring programme recommended in this report. Recommended monitoring for the project includes the monitoring of shoreline at predetermined and bench-marked tide level, beach profiles and drogues at locations given in the EIA report, marine water quality at the location of the intake, brine discharge, sea outfall and a control location, groundwater at a location close to the powerhouse and desalination plant and a control location and quality of product water at 3 specified locations including product water tank. Annual monitoring reports have to be submitted to the Environmental Protection Agency over the monitoring period and shall include fuel and water consumption data and greenhouse gas emission calculations. The overall environmental impacts of the project have been assessed using appropriate matrices and the results indicated that the proposed project has net positive impact. Given that the project has major socio-economic benefits although there would be some negative environmental impacts, it is recommended to allow the project to proceed as proposed.
Technical Report
Environmental impact assessment for the proposed integrated water resource management project HA. Ihavandhoo
(2012-11) Sandcays
This report discusses the findings of a social and environmental impact study under the proposed integrated water resource management project in Ihavandhoo, Haa Alifu Atoll. The project is proposed by United Nations Office for Project Services (UNOPS). The project is targeted at providing potable water to the community and improving rainwater recharge. Potable water is provided by a combination of rainwater and desalinated water, which is a new and unique project for the Maldives. The recharge well system is even more unique. Consequently, several discussions have been held with the Ministry of Environment (represented by EPA), Ministry of Housing and Infrastructure and UNOPS to discuss the several issues. The issues were re-visited during the scoping meeting, the main issues identified by the EPA being the size of the rainwater tanks and good management of the system to ensure that most of the rainwater is used and desalinated water is depended upon as a supplementary source. EPA also has issues with the proposed recharge wells with the main concern lying in the possibility that the recharge wells may help to cause flooding during storm water. However, the project engineer is quite certain that this was not likely and this was also backed by the EIA Consultant. At present Ihavandhoo does not have a piped water supply system and groundwater is used unanimously for all purposes with the exception of bottled water and rainwater for drinking. Several efforts have been made in the past including the construction of public rainwater tanks with public tapbays, which was later replaced by household rainwater tanks of 2500l at each household for easier access but with some compromise on water quality issues. Rainwater, however, could not be depended upon during long, dry periods during the northeast monsoon. With changing climatic patterns worldwide, rainwater can rarely be depended upon. With lack of space for appropriate rainwater collection facilities combined with groundwater contamination and salinization has been seen to cause various health and environmental problems including water-borne diseases. The dependence on groundwater and untreated rainwater is often a cause for concern. Therefore, an integrated water supply system with sustainable groundwater resource is an immediate need for the people of Ihavandhoo, which has a population of over 2750 people in September 2012. The proposed integrated water supply system is designed for maximal use of rainwater supplemented by desalinated water for an average water demand of 50-70 litres per person per day. Raw water is proposed to be drawn from a borehole with 8’’ casing and pumps to pump the raw water to the treatment plant. The treatment for the water is proposed by using Reverse Osmosis technique. The plant will be run by diesel engine and the possibility of alternative energy options such as solar and wind will be considered. The pure water after treatment is collected in glass or fibre-reinforced plastic tanks of adequate capacity determined for Ihavandhoo to be 1000m3 based on EPA guidelines. The water thus collected is introduced in the network so as to reach all the households, institutional and commercial areas with adequate residual pressure through HDPE pipes. The distribution network is designed for over 35 years while the water tank capacity has been based on 15 years as per Government requirements. The proposed IWRM project also comprises of a mechanism to recharge groundwater using a collection of recharge wells made of concrete that will run along the main roads as well as the island periphery. Direct recharge of groundwater is minimized due to urbanisation as permeability is reduced and infiltration surface is minimized. Therefore, this process is assisted by the use of recharge wells that will direct the excess rainwater from roofs to the groundwater lens. However, it must be noted that these recharge wells are not anticipated to cater for storm water drainage. The sole purpose of these wells is to assist groundwater recharge so that the groundwater lens may be sustainably managed. Environmental impacts were assessed for both the construction and operation phase of the project. Most of the environmental impacts of the project have been identified as positive resulting mainly from easy access to safe water supply, improvements to groundwater quality and resulting reduction in water-borne and water-related diseases and improved health of the population. The socio-economic benefits of the project may be considered to outweigh the negative impacts of the project. There are a few negative impacts of the project including the minor impacts of landuse related to the project and clearing of some mature trees that may be required. The impact of clearing would be compensated by replanting mature trees in other areas of the island and, if necessary, planting additional trees. The impact of brine discharge is also considered minor or negligible especially due to the fact that there is no coral cover in the proposed brine discharge location and good mixing will occur due to currents in the area. Since the pipeline is a pressure system, the pipes will be laid above the water table and no dewatering will be required. Hence, no effect on the groundwater lens. Other minor negative impacts include excavation to lay the water distribution network and brine discharge pipe. One of the impacts of the proposed recharge wells would be space constraints to services on the road and the impact would be mitigated by appropriate planning for locating recharge wells and sewerage manholes as well as other such services. The other impact of the proposed recharge wells would be that there may be clogging of the pipes and such clogging may lead to unnecessary flooding in some areas where clogging occurs, especially in areas easily prone to flooding following rain. However, clogging is expected to occur over the long-term, therefore, it is not possible to do field tests to verify this. It has also been seen that recharge is also not much of a use if pumps are used to draw water from the groundwater aquifer, which leads to rapid salinization of the water lens during the dry period. Recharge of groundwater lens also occurs over a large surface due to rainfall. If we consider the sustainable yield estimated for Ihavandhoo, it can be seen that no amount of recharge will help to overcome the problems related to salinization due to increasing use of pumps. In fact, the Maldives receives well over 2000mm of rainfall, which would be more than sufficient to recharge the aquifer. Yet, the aquifer, similar to a rainwater tank, has its maximum capacity limits and cannot overgrow the impact imposed by high rates of abstraction. Therefore, only sustainable rates of pumping can ensure sustainable management of the aquifer. It has been observed from studies carried out for Malé that freshwater exists in pockets. Where the drawn down effect is high, due to the size of pumps and rate of pumping, there is a tendency for the water lens to become more saline at the location where the drawdown is greater. This draw down or lowering of the water table at the point of abstraction, sometimes referred to as the “coning effect” for the freshwater lens, can only be avoided with the use of appropriate technology such as skimming wells and infiltration galleries. The main mitigation measure for the proposed project would be to identify measures to minimize drawdown on the aquifer including the introduction of skimming wells by improving existing wells and enhancing water conservation techniques. The proposed concept of recharge wells is still at a preliminary stage, therefore, it is proposed that the detailed design takes into consideration the findings of this Environmental Impact Assessment, and consultations with the community and relevant government agencies, especially the EPA. It is inevitable that there would be some negative environmental impacts. However, these are minor compared to the positive effects of the proposed system. Yet, monitoring to ensure the effectiveness of the proposed system would be necessary. Therefore, a monitoring component has been suggested which takes in to consideration, the most important elements that require regular checks. This monitoring component will be adhered to and will allow the assessment of changes due to construction and implementation of the proposed water supply system and aquifer recharge system. Monitoring is specifically focussed on water quality, to include feedwater from the borehole (or other source), collected rainwater, groundwater, product water at designated locations and seawater at brine discharge location (upstream and downstream). Reef or marine ecological monitoring may be considered if the proposed location of the brine discharge or intake is found to be of ecological significance. In conclusion, it appears justified from a technical and environmental point of view, to carry out the proposed project to install and operate a piped water supply scheme using rainwater supplemented by desalinated water. However, the recharge well scheme needs to be further evaluated and possibly replaced by or integrated with an alternative scheme such as converting existing household wells to skimming wells to minimize salinization of the groundwater lens. It is also further recommended to consider one of the three islands under this project as a pilot island for the recharge wells instead of all three islands and Ihavandhoo seems to be the most appropriate since the island is higher in elevation compared to the other two and there is a lesser chance of potential flooding, where there is a concern.
Technical Report
Environmental impact assessment for the proposed integrated water resource management project GDH. Gadhdhoo
(2012-12) Sandcays
This report discusses the findings of a social and environmental impact study under the proposed integrated water resource management project in Gadhdhoo, Gaafu Dhaalu Atoll. The project is proposed by United Nations Office for Project Services (UNOPS). The project is targeted at providing potable water to the community and improving the rainwater recharge. Potable water is provided by a combination of rainwater and desalinated water, which is a new and unique project for the Maldives. The recharge well system is even more unique. Consequently, several discussions have been held with the Ministry of Environment (represented by EPA), Ministry of Housing and Infrastructure and UNOPS to discuss the several issues. The issues were re-visited during the scoping meeting, the main issues identified by the EPA being the size of the rainwater tanks and good management of the system to ensure that most of the rainwater is used and desalinated water is depended upon as a supplementary source. EPA also has issues with the proposed recharge wells with the main concern lying in the possibility that the recharge wells may help to cause flooding during storm water. However, the project engineer is quite certain that this was not likely and this was also backed by the EIA Consultant. At present Gadhdhoo does not have a piped water supply system and groundwater is used unanimously for all purposes with the exception of bottled water and rainwater for drinking. Several efforts have been made in the past including the construction of public rainwater tanks with public tapbays, which was later replaced by household rainwater tanks of 2500l at each household for easier access but with some compromise on water quality issues. Rainwater, however, could not be depended upon during long, dry periods during the northeast monsoon. With changing climatic patterns worldwide, rainwater can rarely be depended upon. With lack of space for appropriate rainwater collection facilities combined with groundwater contamination and salinization has been seen to cause various health and environmental problems including water-borne diseases. The dependence on groundwater and untreated rainwater is often a cause for concern. Therefore, an integrated water supply system with sustainable groundwater resource is an immediate need for the people of Gadhdhoo, which has a population of over 2899 people in September 2012. The proposed integrated water supply system is designed for maximal use of rainwater supplemented by desalinated water for an average water demand of 50-70 litres per person per day. Raw water is proposed to be drawn from a borehole with 8’’ casing and pumps to pump the raw water to the treatment plant. The treatment for the water is proposed by using Reverse Osmosis technique. The plant will be run by diesel engine and the possibility of alternative energy options such as solar and wind will be considered. The pure water after treatment is collected in glass or fibre-reinforced plastic tanks of adequate capacity determined for Gadhdhoo to be 900m3 based on EPA guidelines. The water thus collected is introduced in the network so as to reach all the households, institutional and commercial areas with adequate residual pressure through HDPE pipes. The distribution network is designed for over 35 years while the water tank capacity has been based on 15 years as per Government requirements. The proposed IWRM project also comprises of a mechanism to recharge groundwater using a collection of recharge wells made of concrete that will run along the main roads as well as the island periphery. Direct recharge of groundwater is minimized due to urbanisation as permeability is reduced and infiltration surface is minimized. Therefore, this process is assisted by the use of recharge wells that will direct the excess rainwater from roofs to the groundwater lens. However, it must be noted that these recharge wells are not anticipated to cater for storm water drainage. The sole purpose of these wells is to assist groundwater recharge so that the groundwater lens may be sustainably managed. Environmental impacts were assessed for both the construction and operation phase of the project. Most of the environmental impacts of the project have been identified as positive resulting mainly from easy access to safe water supply, improvements to groundwater quality and resulting reduction in water-borne and water-related diseases and improved health of the population. The socio-economic benefits of the project may be considered to outweigh the negative impacts of the project. There are a few negative impacts of the project including the minor impacts of landuse related to the project, however, no clearing is envisaged. The impact of clearing, if any, would be compensated by replanting mature trees in other areas of the island and, if necessary, planting additional trees. The impact of brine discharge is also considered minor or negligible especially due to the fact that there is no coral cover in the proposed brine discharge location and good mixing will occur due to currents in the area. Since the pipeline is a pressure system, the pipes will be laid above the water table and no dewatering will be required. Hence, no effect on the groundwater lens. Other minor negative impacts include excavation to lay the water distribution network and brine discharge pipe. One of the impacts of the proposed recharge wells would be space constraints to services on the road and the impact would be mitigated by appropriate planning for locating recharge wells and sewerage manholes as well as other such services. The other impact of the proposed recharge wells would be that there may be clogging of the pipes and such clogging may lead to unnecessary flooding in some areas where clogging occurs, especially in areas easily prone to flooding following rain. However, clogging is expected to occur over the long-term, therefore, it is not possible to do field tests to verify this. It has also been seen that recharge is also not much of a use if pumps are used to draw water from the groundwater aquifer, which leads to rapid salinization of the water lens during the dry period. Recharge of groundwater lens also occurs over a large surface due to rainfall. If we consider the sustainable yield estimated for Gadhdhoo, it can be seen that no amount of recharge will help to overcome the problems related to salinization due to increasing use of pumps. In fact, the Maldives receives well over 2000mm of rainfall, which would be more than sufficient to recharge the aquifer. Yet, the aquifer, similar to a rainwater tank, has its maximum capacity limits and cannot overgrow the impact imposed by high rates of abstraction. Therefore, only sustainable rates of pumping can ensure sustainable management of the aquifer. It has been observed from studies carried out for Malé that freshwater exists in pockets. Where the drawn down effect is high, due to the size of pumps and rate of pumping, there is a tendency for the water lens to become more saline at the location where the drawdown is greater. This draw down or lowering of the water table at the point of abstraction, sometimes referred to as the “coning effect” for the freshwater lens, can only be avoided with the use of appropriate technology such as skimming wells and infiltration galleries. The main mitigation measure for the proposed project would be to identify measures to minimize drawdown on the aquifer including the introduction of skimming wells by improving existing wells and enhancing water conservation techniques. The proposed concept of recharge wells is still at a preliminary stage, therefore, it is proposed that the detailed design takes into consideration the findings of this Environmental Impact Assessment, and consultations with the community and relevant government agencies, especially the EPA. After discussions with the engineers, it is believed that the system will retain water and about 500m3 of rain will be retained to slowly recharge the aquifer during the dry period or periods with prolonged duration without rain. However, the main problem with the salinization of the aquifer and the making full use of the sustainable yield of the island’s small aquifer lies with the fact that drawdown and coning effect due to the use of pumps in household wells and not with recharge. Also, the potential impact of recharge wells contributing to flooding in a floodprone island like Gadhdhoo is of significance, such a system is not recommended. It is inevitable that there would be some negative environmental impacts. However, most of the impacts of the proposed water supply system are minor compared to the positive effects of the proposed system. Yet, monitoring to ensure the effectiveness of the proposed system would be necessary. Therefore, a monitoring component has been suggested which takes in to consideration, the most important elements that require regular checks. This monitoring component will be adhered to and will allow the assessment of changes due to construction and implementation of the proposed water supply system and aquifer recharge system. Monitoring is specifically focussed on water quality, to include feedwater from the borehole (or other source), collected rainwater, groundwater, product water at designated locations and seawater at brine discharge location (upstream and downstream). Reef or marine ecological monitoring may be considered if the proposed location of the brine discharge or intake is found to be of ecological significance. In conclusion, it appears justified from a technical and environmental point of view, to carry out the proposed project to install and operate a piped water supply scheme using rainwater supplemented by desalinated water. However, the recharge well scheme needs to be further evaluated and possibly replaced by or integrated with an alternative scheme such as converting existing household wells to skimming wells to minimize salinization of the groundwater lens.
Technical Report
Environmental impact assessment for the proposed integrated water resource management project ADH. Mahibadhoo
(2012-12) Sandcays
This report discusses the findings of a social and environmental impact study under the proposed integrated water resource management project in Mahibadhoo, Alifu Dhaal Atoll. The project is proposed by United Nations Office for Project Services (UNOPS). The project is targeted at providing potable water to the community and improving the rainwater recharge. Potable water is provided by a combination of rainwater and desalinated water, which is a new and unique project for the Maldives. The recharge well system is even more unique. Consequently, several discussions have been held with the Ministry of Environment (represented by EPA), Ministry of Housing and Infrastructure and UNOPS to discuss the several issues. The issues were re-visited during the scoping meeting, the main issues identified by the EPA being the size of the rainwater tanks and good management of the system to ensure that most of the rainwater is used and desalinated water is depended upon as a supplementary source. EPA also has issues with the proposed recharge wells with the main concern lying in the possibility that the recharge wells may help to cause flooding during storm water. However, the project engineer is quite certain that this was not likely and this was also backed by the EIA Consultant given that there is overflow from one well to the other, especially in flood prone areas. At present Mahibadhoo does not have a piped water supply system and groundwater is used unanimously for all purposes with the exception of bottled water and rainwater for drinking. Several efforts have been made in the past including the construction of public rainwater tanks with public tapbays, which was later replaced by household rainwater tanks of 2500l at each household for easier access but with some compromise on water quality issues. Rainwater, however, could not be depended upon during long, dry periods during the northeast monsoon. With changing climatic patterns worldwide, rainwater can rarely be depended upon. With lack of space for appropriate rainwater collection facilities combined with groundwater contamination and salinisation has been seen to cause various health and environmental problems including water-borne diseases. The dependence on groundwater and untreated rainwater is often a cause for concern. Therefore, an integrated water supply system with sustainable groundwater resource is an immediate need for the people of Mahibadhoo, which has a population of over 2100 people in mid-2012. The proposed integrated water supply system is designed for maximal use of rainwater supplemented by desalinated water for an average water demand of 50-70 litres per person per day. Raw water is proposed to be drawn from a borehole with 8’’ casing and pumps to pump the raw water to the treatment plant. The treatment for the water is proposed by using Reverse Osmosis technique. The plant will be run by diesel engine and the possibility of alternative energy options such as solar and wind will be considered. The pure water after treatment is collected in glass or fibre-reinforced plastic tanks of adequate capacity determined for Mahibadhoo to be 700m3 based on EPA guidelines. The water thus collected is introduced in the network so as to reach all the households, institutional and commercial areas with adequate residual pressure through HDPE pipes. The distribution network is designed for over 35 years while the water tank capacity has been based on 15 years as per Government requirements. The proposed IWRM project also comprises of a mechanism to recharge groundwater using a collection of recharge wells made of concrete that will run along the main roads as well as the island periphery. Direct recharge of groundwater is minimized due to urbanisation as permeability is reduced and infiltration surface is minimized. Therefore, this process is assisted by the use of recharge wells that will direct the excess rainwater from roofs to the groundwater lens. However, it must be noted that these recharge wells are not anticipated to cater for storm water drainage. The sole purpose of these wells is to assist groundwater recharge so that the groundwater lens may be sustainably managed. Environmental impacts were assessed for both the construction and operation phase of the project. Most of the environmental impacts of the project have been identified as positive resulting mainly from easy access to safe water supply, improvements to groundwater quality and resulting reduction in water-borne and water-related diseases and improved health of the population. The socio-economic benefits of the project may be considered to outweigh the negative impacts of the project. The main negative impact of the project is the diesel-based power and resultant emissions, which has minor to moderate negative cumulative impacts. However, since rainwater is the primary source and desalination is supplementary to the proposed rainwater system, the power requirement is expected to be much lower than depending on RO desalination technology alone. There are a few negative impacts of the project including the minor impacts of landuse. The impact of brine discharge is also considered minor or negligible especially due to the fact that there is no coral cover in the proposed brine discharge location and good mixing will occur due to currents in the area. Since the pipeline is a pressure system, the pipes will be laid above the water table and no dewatering will be required. Hence, no effect on the groundwater lens. Other minor negative impacts include excavation to lay the water distribution network and brine discharge pipe. One of the impacts of the proposed recharge wells would be space constraints to services on the road and the impact would be mitigated by appropriate planning for locating recharge wells and sewerage manholes as well as other such services. The other impact of the proposed recharge wells would be that there may be clogging of the pipes and such clogging may lead to unnecessary flooding in some areas where clogging occurs, especially in areas easily prone to flooding following rain. However, clogging is expected to occur over the long-term, therefore, it is not possible to do field tests to verify this. It has also been seen that recharge is also not much of a use if pumps are used to draw water from the groundwater aquifer, which leads to rapid salinization of the water lens during the dry period. Recharge of groundwater lens also occurs over a large surface due to rainfall. If we consider the sustainable yield estimated for Mahibadhoo, it can be seen that no amount of recharge will help to overcome the problems related to salinization due to increasing use of pumps. In fact, the Maldives receives well over 2000mm of rainfall, which would be more than sufficient to recharge the aquifer. Yet, the aquifer, similar to a rainwater tank, has its maximum capacity limits and cannot overgrow the impact imposed by high rates of abstraction. Therefore, only sustainable rates of pumping can ensure sustainable management of the aquifer. It has been observed from studies carried out for Malé that freshwater exists in pockets. Where the drawn down effect is high, due to the size of pumps and rate of pumping, there is a tendency for the water lens to become more saline at the location where the drawdown is greater. This draw down or lowering of the water table at the point of abstraction, sometimes referred to as the “coning effect” for the freshwater lens, can only be avoided with the use of appropriate technology such as skimming wells and infiltration galleries. The main mitigation measure for the proposed project would be to identify measures to minimize drawdown on the aquifer including the introduction of skimming wells by improving existing wells and enhancing water conservation techniques. The proposed concept of recharge wells is still at a preliminary stage, therefore, it is proposed that the detailed design takes into consideration the findings of this Environmental Impact Assessment, and consultations with the community and relevant government agencies, especially the EPA. It is inevitable that there would be some negative environmental impacts. However, these are minor compared to the positive effects of the proposed system. Yet, monitoring to ensure the effectiveness of the proposed system would be necessary. Therefore, a monitoring component has been suggested which takes in to consideration, the most important elements that require regular checks. This monitoring component will be adhered to and will allow the assessment of changes due to construction and implementation of the proposed water supply system and aquifer recharge system. Monitoring is specifically focussed on water quality, to include feedwater from the borehole (or other source), collected rainwater, groundwater, product water at designated locations and seawater at brine discharge location (upstream and downstream). Reef or marine ecological monitoring may be considered if the proposed location of the brine discharge or intake is found to be of ecological significance. In conclusion, it appears justified from a technical and environmental point of view, to carry out the proposed project to install and operate a piped water supply scheme using rainwater supplemented by desalinated water. However, the recharge well scheme needs to be further evaluated and possibly replaced by or integrated with an alternative scheme such as converting existing household wells to skimming wells to minimize salinization of the groundwater lens.
Technical Report
Environmental impact assessment for the proposed project to upgrade the sewerage system Manadhoo Noonu Atoll, Maldives
(2013-09) Sandcays
This report discusses the findings of an environmental impact study under the proposed sewerage system upgrading project at N. Manadhoo. The project is proposed by Fennaka Corporation limited. The project entails upgrading the sewerage system to improve the existing sewerage treatment plant. The proposed upgrading involves incorporation of sea outfall with pumping station as emergency outfall and modification or replacement of two fiber tanks in the sewage treatment plant. The project has been proposed to repair the exiting treatment plant as at the moment, due to damages to the STP raw wastewater is discharge into the lagoon directly. Upon recommendation from the consultants and in accordance with the existing guidelines, an emergency bypass has been included in the design with one additional pumping station. The emergency outfall will pump wastewater beyond the house-reef at about 15m depth. A number of alternatives to the proposed project components have been identified in this document. Of these, the recommended alternative involves changing the proposed outfall location slightly to east which will reduce the length of outfall pipe and hence lower the implementation cost considerably. Other alternatives include considering different emergency outfall environments such as ground and lagoon. Environmental impacts were assessed for both the construction and operational phase of the project. Most of the environmental impacts identified for the proposed development were positive; these include reduced pollution of the marine environment and increased aesthetic value of the beach. The main negative environmental impacts of the project would be temporary loss of groundwater quality during the construction phase due to dewatering and small amount of sedimentation around house-reef induced from installing the emergency outfall. The latter could be regarded as insignificant due to its small magnitude and spatial distribution. The proponent is willing to undertake monitoring during and after the construction phase in addition to undertaking the mitigation measures proposed by the consultants. The main mitigation measures for this project during the construction phase are similar to other construction projects such as dust control plans, working during low- tide as much as possible and rigorous supervision. As for the operational phase, implementation of backup systems and trained maintenance staff to service the Sewage Treatment Plant (STP) and regular check-ups were suggested in addition to monitoring seawater quality around the outfall location. In conclusion, it appears justified from a technical, administrative and to some extent environmental point of view, to carry out the proposed project to upgrade and repair the existing sewerage system. However, there are alternatives that may be more suitable and shall be considered with caution and after understanding the costs and discussions with relevant government authorities.

Academic Articles -- ޢިލްމީ ލިޔުންތަކުގެ ޖަމާ

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