Dr Jessica Salas, Kahublagan Sang Panimalay Foundation Philippines


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Regional Conference for Southeast Asia on Rainwater Harvesting in IWRM: An ExChange of

Policies and Learnings

November 25-26, 2008
Davao City

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Dr Jessica Salas, Kahublagan Sang Panimalay Foundation Philippines

  1. 1. Overview of Global Trends in Rainwater Harvesting Regional Southeast Asia Conference on RAINWATER HARVESTING IN IWRM November 25-26, 2008, Davao City, Philippines Jessica C. Salas, Past President, IRCSA I
  2. 2. Greetings from IRCSA and the Rainwater Partnership <ul><li>Contents of this Presentation: </li></ul><ul><ul><li>Global Trend in Rainwater Harvesting </li></ul></ul><ul><ul><li>Examples of Rainwater Utilization Practices </li></ul></ul><ul><ul><li>Focus in South East Asia </li></ul></ul><ul><ul><li>Institutions in RWH Development & Advocacy </li></ul></ul><ul><ul><li>The Future of Rainwater Harvesting </li></ul></ul>
  3. 3. Rainwater Utilization Trend among Developed Countries <ul><li>Integration in public water supply (dual or multi source water supply) </li></ul><ul><li>Government Policies offer incentives & exact fees: subsidies, tax rebates, eco tax for processed water, sealing fee, required minimum storage based on covered area. </li></ul><ul><li>Increasing commercialization </li></ul><ul><li>Use in high-rise buildings </li></ul>
  4. 4. <ul><li>Used for flood control and sustainable drainage </li></ul><ul><li>A requirement for ground water recharge in sealed surface </li></ul><ul><li>Recognized as effective tool for demand management </li></ul><ul><li>Expected to impact on reduced investments in large water infrastructures </li></ul>
  5. 5. <ul><li>Conducted studies on how RWH mitigate climate change </li></ul><ul><li>Conducted studies on how RWH make communities adapt to climate change </li></ul>
  6. 6. Trend in Developing Countries <ul><li>Primary source of water in some areas </li></ul><ul><li>World Health Organization set standards for rainwater as drinking water </li></ul><ul><li>Some governments do not invest in rainwater harvesting. Priorities are on centralized services for irrigation and drinking water. </li></ul><ul><li>Low level of understanding of the ecological and economic impact of RWH </li></ul><ul><li>Weak/absence of structural support such as legislation, service providers, credit, education, information dissemination, guidelines. </li></ul>
  7. 7. <ul><li>Need for RWH integration in watershed management and IWRM </li></ul><ul><li>Damaged ecosystems lead to depletion of water and land resources. Countries use man-made water storage to supplement natural storage of water. </li></ul><ul><li>Some countries use RWH to re-condition soil caused by desertification. </li></ul><ul><li>On-going studies on how RWH increase resiliency to weather impact of climate change. </li></ul>
  9. 9. Japan, Miyake Island <ul><li>Trees are used to catch rainwater </li></ul><ul><li>Rainwater, considered as celestial water, used for drinking and for brewing tea </li></ul><ul><li>Tap water which is available, is only used for flushing toilets </li></ul><ul><li>Population dislikes chemical in water </li></ul>
  10. 10. Tokyo, Japan <ul><li>Published guidelines for rainwater utilization. </li></ul><ul><li>Assisted households and businesses in planning </li></ul><ul><li>Local authorities were granted subsidies & interest-free loans </li></ul><ul><li>Annual rainfall: 1,400 mm </li></ul>Example: 1993. EDO Tokyo Museum with 2,500 m3 tank & roof area of 30,000 m2 used as catchments.
  11. 11. India <ul><li>Practiced both in cities & rural areas </li></ul><ul><li>Rooftop catchments & ground water recharge are the most popular practices </li></ul><ul><li>Government Policies & Research support RWH </li></ul><ul><li>The ground water artificial recharge experiment of the Central Groundwater Board showed: </li></ul><ul><ul><li>Using check dams, resulted in a storage of 4,600 to 22,180 m3 & a rise of 0.8 to 9.9 m in water level, 9 to 30 hectares benefited </li></ul></ul><ul><ul><li>Injection wells with roof rainwater resulted in a rise in water level by 0.51 m. </li></ul></ul>
  12. 12. Taiwan <ul><li>Promotion of industrial/residential rainwater use began in 1996. </li></ul><ul><li>Total investment– 50.73 million NT$ </li></ul><ul><li>Total storage capacity 20,538 tons </li></ul><ul><li>Substituted water supply is 700,000 tons. </li></ul><ul><li>Main uses: toilet flushing (84.1%), irrigation (8.8%), cleaning (5.5%), landscaping (1.3%) </li></ul>
  13. 13. Taiwan Sub basin Planning for Flood Control Agriculture
  14. 14. China <ul><li>Before RWH </li></ul><ul><li>Yield/water consumption –wheat: 0.4 to 0.5 kg/m3; </li></ul><ul><li>corn 1.7 to 2.0 kg/m3 </li></ul><ul><li>Farmers’ income >0.5USD </li></ul><ul><li>After RWH </li></ul><ul><li>Increase in yield/water consumption - (wheat) 51.3 to 60.6%; 9.6 to 13.6% (corn) </li></ul><ul><li>Increase in Yield of 20-88% </li></ul><ul><li>1.3 million with access to drinking water </li></ul><ul><li>2.2 million tanks built </li></ul><ul><li>200,000 hectares of land irrigated </li></ul>Loess Plateau Annual Rainfall : 300-400 mm, No other water source
  15. 15. Rainwater Harvesting in Gansu, China
  16. 16. Africa
  17. 17. Australia: Olympic Village Saving 55% of fresh water with RWH Annual Rainfall – 850 mm
  18. 18. Caribbean <ul><li>Haiti- every household and building use rainwater for non-potable use </li></ul><ul><li>Barbados – A building code requires all residential building area 3,000 ft, a 6000gal capacity reservoir. Tax incentive $1,500 to $.50/gal of installed tank capacity </li></ul>
  19. 19. England <ul><li>Annual Rainfall: </li></ul><ul><li>RWH Industry growth rate doubles every year for the last 3 years. </li></ul><ul><li>Annual growth is £ 1,000,000 or US$1.8 M </li></ul><ul><li>Sustainable Building Strategy suggests a 25% reduction in potable water use. </li></ul><ul><li>Planning Policy Guideline 25 proposes RWH to reduce potential runoff & control flooding. </li></ul><ul><li>Example: London’s annual rainfall: 613 mm </li></ul><ul><li>Thames Water, its water supply company utilizes 55% of rainfall </li></ul><ul><li>Latest project is the Millennium Dome </li></ul>
  20. 20. Millennium Dome Roof Area, 100,000 m 2 50 m high. Satisfies 20%of 500 m 3 requirement of toilets .
  21. 21. Belgium 1999 Code of Vlaamse Milieunaatschapij: all new and repaired houses to install rainwater facilities with minimum cistern capacity of 3,000 gal, using at least 50% of surface, and must have an overflow or seepage system. The law is supported with a financial grant. .The University of Ghent has 136 apartments for students all using rainwater for toilets. Leonard Bus Co., - for using rainwater for cleaning, savings of 2,000 m2 of fresh water
  22. 22. Experiences in South East Asia Bangladesh, Cambodia, Indonesia, Malaysia, Philippines, Singapore, Thailand, Vietnam
  23. 23. Indonesia <ul><li>February 23, 2007 – State Ministry for the Environment & the Jakarta Administration made a call to promote rainwater harvesting. </li></ul><ul><li>Annual Rainfall: 2,500 to 3,000 mm </li></ul><ul><li>Tsunami and earthquake victims in Nias Island (711,000) population received rainwater harvesting facilities </li></ul>Kaibolafin Village on Kola Island survive on a single catchment from a church roof & a single cistern. www.irc.nl/pmt
  24. 24. Bangladesh <ul><li>RWH is not a way of life. </li></ul><ul><li>Massive distribution of wells and water pump. </li></ul><ul><li>After 40 years of massive ground water withdrawal in the sedimentary soil, arsenic contamination of water was experienced. </li></ul><ul><li>“ The largest mass poisoning of a population in history… the scale of this environmental disaster is greater than any seen before .” A German Daily Newspaper </li></ul><ul><li>59 out of 64 districts are affected . </li></ul><ul><li>We are happy to see that the government has put emphasis on the use of rainwater for which we have long been fighting for.” Chief, Dhaka Community Hospital </li></ul>
  25. 26. Singapore <ul><li>¾ of the land is used as catchment for rainwater. </li></ul>Study of rainwater from the Bedok Area says, water quality is comparable with water coming from a protected watershed .
  26. 27. Vietnam <ul><li>Annual rainfall is 120 to 300 cm. </li></ul><ul><li>Sources of water: surface & ground. Some rain collected during rainy season. </li></ul><ul><li>Arsenic contamination of groundwater beginning to show. </li></ul><ul><li>Rainwater jars and filtration system is the response to the situation (Country report on Drinking Water Quality ) </li></ul><ul><li>HANDS ON SAIGON built 100 tanks for women in Can Gio district. </li></ul><ul><li>UNICEF conducts training on rainwater tank construction. </li></ul>“ Only rich people can afford rainwater tanks.”
  27. 28. Cambodia <ul><li>Annual Rainfall is 1,400 mm (central plain) & 3,800 mm (mountains) </li></ul><ul><li>Widespread use of well water, high concentration of arsenic found. </li></ul><ul><li>85% of farmers rely on rain. </li></ul><ul><li>Income of $1 a day </li></ul>
  28. 29. <ul><li>Project of Engineers without Borders (EWB) – rainwater tank for 1,200 school children. </li></ul><ul><li>Project of Oxfam: construction of 17 RWH pools & 29 canals </li></ul>
  29. 30. Thailand <ul><li>1979, the Royal Govt declared a policy of water resources dev’t and jars and tank construction of drinking water started. </li></ul><ul><li>Today, most households have 1 household tank and a membership in a community tank. </li></ul><ul><li>After 10 years, 8 million tanks have been constructed. Private sector competition brought prices down but education lagged behind and incidence of diarrhea increased. </li></ul>
  30. 31. Philippines <ul><li>SWIP project (small water impounding project) started building RWH units in 2002. </li></ul><ul><li>NGOs: (PCWSS) constructed ferro cement tanks in the islands of Tawi Tawi, Mindanao (2000) </li></ul><ul><li>(Kahublagan) conducts studies & projects in Capiz & Iloilo (since 1983) </li></ul><ul><li>No gov’t policy to promote rainwater harvesting. </li></ul><ul><li>Private sector: Households & industries such as the Cebu Export Processing Zone, banana plantations, resorts and hotels use rainwater harvesting. </li></ul>
  31. 32. LAO PDR WSP Lao
  33. 34. International Rainwater Catchment Systems Association With Regional Networks in 1. North America 2. Latin America & the Caribbean 3. Europe 4. South and East Africa 5. Middle East 6. South Asia 7. East Asia 8. Australia
  34. 35. Rainwater Partnership <ul><li>Based in UNEP </li></ul><ul><li>IRCSA as a founding Partner </li></ul><ul><li>60 member-partners including country governments and UN agencies, and international NGOs </li></ul><ul><li>Headed by an Advisory Council </li></ul>
  35. 36. THE FUTURE <ul><li>Delphi Study conducted in Germany by 45 international water experts: </li></ul><ul><li>Groundwater pollution will continue because of farming. </li></ul><ul><li>Centralized public water will decrease its prominence because of cost </li></ul><ul><li>Technology requisites for a new system with high degree of hygiene is existing now. </li></ul>
  36. 37. <ul><li>Rainwater Utilization is socially acceptable backed up by a state of the art technology. </li></ul><ul><li>5 to 20% max. of households will be connected to a central process water system in 2010. </li></ul><ul><li>Only 10% of the newly installed toilets will be using processed water. </li></ul><ul><li>By 2020, it will be possible to build houses that are self sufficient in water usage. </li></ul>
  37. 38. “ The future belongs to a decentralized infrastructure which is flexible enough to adapt to technical progress when environmental policy, local conditions and/or individual needs change.” Martin Bullerman Member, Water Working Group Delphi Study
  38. 39. Rainwater Harvesting is the decentralized water technology for the next millennium.
  39. 40. Thank You