IMPROVING WATER SECURITY IN TSUNAMI EFFECTED AREAS IN SRI LANKA THROUGH DOMESTIC RAIN WATER HARVESTING

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1 IMPROVING WATER SECURITY IN TSUNAMI EFFECTED AREAS IN SRI LANKA THROUGH DOMESTIC RAIN WATER HARVESTING T. Ariyananda, Director, Lanka Rain Water Harvesting Forum, Abstract Since the tsunami of 26th December 2004 the water sources around the coast of Sri Lanka still remain contaminated. Sea water intrusion to wells has made the present sources which are mainly wells unusable even after desalination. It is estimated that 10 pipe bourn water schemes were damaged and 50,000 house connections were damage during the tsunami. In addition it is estimated more than 60% of the wells are still microbiologically contaminated. Therefore, the people living in these areas face serious problems in fetching quality water for domestic use. Especially since the bowsers supply of water by the donor agencies and government is also now diminishing. Rainwater harvesting (RWH) through roof catchments has been introduced in three of the tsunami effected districts in Sri Lanka. More than 1000 rain water harvesting units have been built for the tsunami reconstructed houses in two districts in the south and one district in the east. Rainwater harvesting through roof run off has significantly address the shortage of domestic water at household levels. The benefits experience by these householders are : Easy access to clean drinking water, less time spend on collecting water, skilled enhancement in the village, less reliance on external water providers, more water security at household level, better sanitation practice due to more water available. Government policy and support too has encouraged the uptake of rain water harvesting in the tsunami reconstruction process. Ministry of Urban Development and Water Supply incorporated rain water harvesting in the design of tsunami reconstructed houses, which is now an essential requirement in a standard tsunami house. In additional the policy propose to amend legislation (UDA by Laws) to incorporate RWH in new construction in other areas of the country as well. Introduction th On the 26 December 2004, magnitude of 9.3 earthquakes off the south coast of Sumatra generated tsunami wave that left over 280, 000 people dead or missing in Asia and Africa. Hundreds of thousands of homes were destroyed resulting in a humanitarian crisis in the hardest hit countries. Although Sri Lanka is approximately 1600 Km from the epicentre it was the second hardest hit country in terms of loss of human lives. Over 35,000 people were reported dead or missing, more than 85,000 homes were destroyed or severely damaged along the coast of Sri Lanka (ADB Report 2005). The magnitude of the tragedy continues to dominate the social and political structure of the country even after 2 years since the disaster. Effect on water supply In most areas of Sri Lanka, the availability of potable drinking water quickly became a major concern for relief efforts, both from the perspective of life requirement and from concern over potential spread of waterborne disease from contaminated water supply. The largest costal urban communities of Sri Lanka are supplied by treated and pipe surface and groundwater supplies managed by National Water Supply and Drainage Board (NWSDB). The primary damage to the treated water supply involved break in pipelines which were completely destroyed at several river and estuary crossing. Additional leaks were caused when the force of tsunami waves sheared off the water connections to individual dwellings. Repairs to the distribution system began soon after the tsunami events, and as of September 2005, pipe water services had been restored to most areas previously served and plans are under way to expand the distribution system.

2 While the NWSDB served about 30% of the country s general population via 287 water supply systems ( using tube wells and surface water systems, many of the coastal areas rely on individual or community wells for potable water. The tsunami immediately inundated and contaminated more than 40,000 of these wells in Sri Lanka (United Nations Environment Programme, 2005; ADB report, 2005) primarily close to the coastline. In most affected areas, the open dug wells were instantly filled with the sea water and large volumes of saltwater were injected into the freshwater lens. Many wells were also contaminated with organic and inorganic debris from the flood waters, rending them unsuitable until they were cleaned and disinfected. In addition, the seawater inundated lowlying areas resulting in infiltration of saline water into aquifer. During the post tsunami clean up, government, non- government organisation (NGO s) and foreign and local voluntary groups and local citizens began pumping contaminated wells and treating them with chlorine disinfectant. From the perspective of removing saltwater and restoring potable drinking water quality, the emergency procedure used may have caused more salt water intrusion from below rather than its removal from upper part of the saturated zone. In addition, the purged well water was often discharged on the land surface close to the wells, allowing contaminated water re-enter the aquifer. Water supply in the first phase of the emergency was provided by water tanks (bowsers) to the Transitional Shelter Sites (TSS) which housed the tsunami victims. Where ever, the network was available NWS&DB quickly repaired the damaged pipeline and restored the household connections. However, during the rehabilitation process when the victims started going back to their own homes or were housed in newly constructed houses, domestic water supply became a major issue due the following reasons. 1. Ground water sources were still contaminated or have high salinity. 2. No water supply in relocated houses, since they are build in new lands 3. Delays in construction of water supply schemes 4. In frequent and reduction of bowsers water supplies 5. Drying up of ground water sources 6. Pipe water supply is not reliable and costly In march 2006 a project was implemented by Lanka Rain Water Harvesting Forum in the Southern province with funding from Malteser International, Unicef and USAID and in the East Province funding by NWS&DB/Danida Sri Lanka tsunami project to construct rain water harvesting systems in tsunami reconstructed houses. Implementation Initially a survey was conducted in the three tsunami effected districts in the Southern province in Galle, Matara and Hambantota and in the district of Ampara in the Eastern province to identify the potential and feasibility of incorporating rain water harvesting systems for domestic water supply in tsunami affected areas. Potential project locations were identified by first identifying the list of on going approved housing projects in the 4 districts. Then these sites were visited to assess the water needs, site layout, number of houses, house size, list of beneficiaries and contractors/funders. To obtain the felt needs and acceptance of rain water systems for drinking purposes a number of meeting were held with District Secretariat staff, Divisional Secretariat staff, Ministry of Urban Development and Water Supply Staff, National Water Supply & Drainage Board head office staff, District office staff,

3 Divisional office staff, Non government organization involved in housing, water supply and sanitation villages and householders. Based on the above interviews and surveys a list of potential sites and locations for implementing rain water harvesting units were prepared. Table 1: List of number of households identified in the 4 district District Division Number of beneficiary Households Galle Bentota, Ambalangoda, Habaraduwa, 1188 Hikkaduwa, Balapitiya Matara Devinuwara, Dickwella, Matara, 588 Weligama Hambantota Hambantota, Tangalle, Ambalantota, 1560 Tissamaharama Ampara Kalmunai, Pottuvil, Thirukkovil 500 Design of Rain Water Harvesting System Storage requirement for the rain water harvesting unit was calculated using the supply side approach which uses rainfall and catchment area to calculate the storage size. Considering the factors such as rain fall, roof area, runoff coefficient and user numbers, the following tanks sizes were determined for each district using the rain water performance calculator program developed by Warwick University UK ( The tanks sizes were selected which gives above 80% reliability and satisfaction. Parameters/District Galle Matara Hambantota Ampara Av. Annual rainfall 2200 mm 1400 mm 650 mm 1100 mm size of roof 50 m 2 50 m 2 50 m 2 50 m 2 runoff coefficient user numbers/ Daily demand 5 / 100 l 5 / 100 l 5 / 100 l 5 / 100 l tank size 3-5 m 3 5 m 3 8 m 3 8 m 3 Based on the previous experience of LRWHF, low cost, availability of trained masons, ease of operation and maintenance and user preference, the pumpkin shaped Ferro cement tanks was selected for construction. Figure 1: 5 m 3 Pumpkin shaped Ferro cement Tank Project experience

4 During the first year of the project a total of 1000 households were targeted in Galle and Matara district and 200 households were targeted in Ampara district. At the end of the first year 1208 households received 5 m 3 tanks for each family and 8 resource centres were established in schools and temples in the Southern Province ( Galle and Matara district). In the Eastern province 200 households received 8m 3 tanks and 10 demonstration centres were established. Households for construction of rain water harvesting system were selected through, first conducting awareness programs at village/community level and requesting the interested householder to apply for a rain water harvesting system through their Grama Niladharia (Village Administrator). After monitoring of the preliminary sites and selected houses, the final selection of householders were made by using a selection criteria. Selection criteria was design to serve people who are living in the areas where the ground water quality is poor, in the concentrated areas where water borne disease is high, in the areas where no future plan of the NWSDB to supply water, people with low income and householders are willing to contribute in the form of unskilled labour. The project also conducted masons training programs to train the locally identified masons and youth in the area for future construction and enhancement of skills in the areas. Extensive awareness campaign was conducted through exhibition and poster competition in schools, awareness programs to government and non government officials and by the use of mobile unit. The project utilized a participatory methodology to ensure the active involvement of government, non- government and local partner organizations, Community Based Organisations, and beneficiaries in all important aspects of the project cycle. Where ever, the community contribution was not obtained when rain water systems were constructed in unoccupied housed (due to pressure from funding agencies to achieve targets and local government agencies), the system were neglected and misused. This was mainly experienced in Ampara district, where project activities were also delayed due to security situation in the area. The following benefits were identified by the households who received a rain water harvesting system. Identified benefit to the community 1. Easy access to clean drinking water 2. Less time spend on collecting water 3. Skilled enhancement in the village 4. Less reliance on external water providers 5. More water security at household level. 6. Better Sanitation practice due to more water available. Implementation of the project was supported by the Government policy which encouraged the uptake of rain water harvesting in the tsunami reconstruction process. Ministry of Urban Development and Water Supply incorporated rain water harvesting in the design of tsunami reconstructed houses, which is now an essential requirement in a standard tsunami house. In additional the policy propose to amend legislation (UDA by Laws) to incorporate rain water harvesting in new construction in other areas of the country as well. Lessons learned from the first phase of the project Awareness programs to the householders are very important.

5 Training on Operation and Maintenance of the system is very important to the householders holders of rainwater harvesting tanks. However, a first flush system which operates automatically would be more suitable since most people seem to neglect emptying the first flush pipe. Some households show reluctance for drinking rain water. 52% of the rainwater harvesting tank receivers are reluctant to drink the rainwater while 30% of them drink. Better awrness on water quality is planned for next phase. Householdes should be educated on health & hygiene, through awareness programs arranged in collaborating with Medical Officer of Health, Public and Health Inspectors in the local areas to maintain the sustainability of the project. Community contibution and involvment was less or non in Ampara district due to dealys in allocating the housholdes to families, sustainability of the constructed rain water harvestign systems are in doubt. Recommendation and Conclusion All houses in tsunami areas should be constructed with rain water harvesting system to reduce the scarcity of existing water sources. This would supplement other sources whether it is pipe water, wells or other sources. It will create less pressure on pipe water system enabling the authorities to provide coverage to more householders at the same time reduction in cost of treatment. Rain water system also offer a better quality of water, since 60%-78% of the well water are thought to be still contaminated in the areas (Satori & Giusti 2006). In order to ensure that good quality rain water is collected and used, all households has be trained on operation and maintenance of the system. Quality of rainwater should be popularized therefore more people will use for drinking, specially in areas where other sources are contaminated or mineralized. Simple water treatment such as boiling and Solar water disinfection methods (SODIS) should be introduced for drinking water treatment. Households should be provided with simple low cost water quality testing kits so they themselves can monitor the quality and make improvements. Community Contribution and involvement in the construction of the rain water harvesting system should be a must in implementation of future projects. Excess rain water should be used for recharging and improving the quality of ground water table in the area. This will improved salinity levels in the wells in the future. Reference Illangasekarae T. Tyler S.W. Clement T.P, Villholth K. G, Perera A.P. G. R., Obeysekara J, Obeysekara A., Panabokke C.R., Hyndman D.W, Cunningham K.J, Kaluarachchi J.J., Yeh W. W. G, Genuchten M.T van, Jensen K ( 2006) Impact of the 2004 tsunami on ground water resources of Sri Lanka. Water Resources Research, Vol. 42, W Joint Asian Development Bank (ADB), Japan Bank of International Cooperation and World bank, Sri Lanka Post tsunami recovery program: Preliminary Damage and Needs

6 Assessment, Colombo, Sri Lanka, January ( Satori R. & Giusti A. (2006) Challenges of tsunami and Conflict affected rural water supply in Sri Lanka. 32 nd WEDC International Conference, Colombo, Sri Lanka. United Nations Environment Programme (2005) After the Tsunami: Rapid Environment Assessment, Nirobi ( )