Introduction l 1190 islands l 200 inhabited islands
Introduction l 1190 islands l 200 inhabited islands l Population - 270, 000 l Capital, Male’ – 74, 000 l Annual rainfall – 1980 mm l Elevation – Less than 2 m above sea level
Water Resources Groundwater – private individual wells public mosque wells Rainwater – private rainwater tanks public rainwater tanks Traditionally the population of Maldives has been dependent on shallow wells for its drinking water
l Desalinated Water: Available in all tourist resorts, the capital Male’ and Kandholhudhoo island Bottled Water : Imported from different countries as well as produced in Maldives
History of water supply and sanitation in Male’ 1906 – Groundwater problems identified and construction of public rainwater tanks began 1970’s - Frequent outbreaks of waterborne diseases due to groundwater contamination 1980’s - Community and household rainwater tanks and comprehensive sewerage system built 1990’s - Desalination found to be necessary and expanded steadily to meet increasing demand
Occurrence of groundwater resources Groundwater found at shallow depths Usually less than 2 m below ground Lens usually very thin Less than 12 m in most islands Less then 2 m in many
Vulnerability of groundwater resources Because they are shallow, groundwater resources are prone to pollution from above Because lenses are thin, they are prone to increased salinity as a result of over extraction Sea level rises have also increased the threat to Maldives’ groundwater
Groundwater pollution from poor household sanitation Relatively few heavy industries Intensive agriculture on only a few islands Major source of groundwater pollution is poor household sanitation Septic tanks and soakaways are often corroded, poorly built or not maintained
Highly permeable soils encourage pollutant transport Inhabited areas have usually been cleared of vegetation Soils are highly permeable sand Groundwater movement can be quite rapid Pollutants can be transported over long distances
Households depend on their wells Each household has its own well Well water generally used for bathing only During dry season, because rainwater storage is insufficient, well water sometimes used for cooking and drinking Has a significant impact on health
High demand for groundwater leads to increased salinity Use of electric pumps has increased, but over extraction can even occur where simple dhanis are being used Despite relatively low consumption on the rural islands (80 – 110 L/p/d) population densities are sometimes very high Increased salinity can result
Problems exacerbated by high population densities Problems of pollution and over-extraction worsen where population densities are high Island Area (hectares) Population (2000 census) Population density (persons/hectare) R. Kadholhudhoo 4. 40 2650 602 Lh. Hinnavaru 7. 24 3156 436 187. 00 70278 376 B. Thulhaadhoo 4. 97 1822 367 Sh. Komandoo 5. 96 1526 256 Lh. Naifaru 14. 27 3570 250 M. Dhiggaru 4. 61 872 189 M. Maduvvari 3. 10 455 147 K. Gulhi 5. 50 613 111 B. Eydhafushi 22. 20 2379 107 K. Male’
Factors other than population density influence vulnerability Geographical factors High water tables Narrow island width Economic factors Limit ability of communities to build good sanitation facilities Solid waste difficult to dispose of
Infrastructure provided to address these problems Sewerage systems built to protect groundwater from pollution Rainwater storage tanks provided Free for community use Cost recovery basis to households On Kadholhudhoo and Male’, desalination has become necessary Plans to provide desalinated water for other severely affected islands
Desalination in Maldives In some islands the only means of providing a safe water supply is by desalination Desalination capacity in Male’ has been increased from 200 m 3/d in 1988 to 5800 m 3/d today Desalinated water is provided through a pipe network and is used for all purposes except toilet flushing Those who cannot afford to have house connections are provided with water from tap bays
Water Tariffs and Charges in Male’ Consumer Group Rate of subsidy/Tax Price to consumer, per m 3 Domestic household Up to 90 L/day MRf 25. 32 (band A) (US$1. 99) “ 90 – 270 L MRf 75. 95 (band B) (US$5. 96) “ 270 L and above MRf 101. 26 (band C) (US$7. 94) Institutions Metered flat rate MRf 75. 95 (US$5. 96) Commercial Metered flat rate MRf 101. 26 (US$7. 94) • Note: Fixed Line charge MRf 30 per month (US$2. 35) • The tariff covers water and sewerage • Average price for domestic customers is MRF 71. 36(US$5. 60)
Development of desalination capacity in Male’ (m 3/d) Desalination capacity has increased steadily since 1988 Plants donated by various countries have been complimented by plants installed by MWSC
Improved energy efficiency Since installation of desalination plants by MWSC in 1995 energy consumption for water production has fallen from 10 k. W/m 3 to 3 k. W/m 3 in 2002 Due to these advances in energy recovery the cost of production has decreased Costs are US $3. 65 per m 3 which includes production, operation, maintenance and administrative costs
Desalinated water is expensive in Male’ Average household spends between US $ 40 – 60 per month on water ( 6 – 9% of their income) if they use this for their basic needs Advantage of the present arrangement is public have the choice to use groundwater, rainwater or desalinated water. Most people use three types of water Application of charges has made public aware of conserving water
Desalination outside Male’ Most widely used in the resort islands which have their own desalination plants Besides the resorts most densely populated island R. Kandholhudhoo (4. 40 hectares in area) has a desalination plant 50 m 3/day plant costs US $102, 000 for purchase, transport and installation Household connections are not provided but water is available from a tap bay
Desalination in Kadholhudhoo Cost for filling 20 litre container is US $0. 16 therefore cost per m 3 is US $7. 84 Tariff covers cost of operations and routine maintenance but not for replacing membranes which can be very expensive Although the capital cost was met by government this is not being recovered
Summary: Maldives experience with desalination Desalination has been a success in Male’ – economies of scale and ease of operation and maintenance Since charges were introduced in 1996, supply has been able to meet demand A reliable and safe source of water – no epidemics of waterborne disease since its introduction
Summary: Maldives experience with desalination Desalination in rural islands had some problems Difficult to operate and maintain Cost recovery difficult on a small scale Level of service has to differ from Male because of difference in income levels Demand dependent on availability of rainwater Reliance on imported fuel and spare parts is a risk Alternative policies for sustainable development are sought
Policies for the sustainable development of water resources Increase household and community rainwater harvesting in the rural islands Pilot new schemes such as community groundwater systems (infiltration galleries) Improved land use planning and introduction of groundwater protection zones Protection of groundwater quality through improved sewage treatment and disposal Improvement of degraded groundwater resources Desalination where necessary in most densely populated islands
Thank you for your attention
- Slides: 26
