Impact of Climate Changes on Drinking and Sanitation Water Use in the Rural Community of the Dry Zone Sri Lanka

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1 Impact of Climate Changes on Drinking and Sanitation Water Use in the Rural Community of the Dry Zone Sri Lanka Prof. G.M. Bandaranayake, Senior Lecturer, Water Resources Studies, Department of Geography, University of Sri Jayewardenepura, Sri Lanka

2 Climate change is one of serious problems of the present world on which urgent attention at global level should be focused Its worst effect is impact on water resources. Thus our (water scientists, water users, water professionals and water planners ) concern over impact of climate on water resources is urgently needed The term climate change has two aspects 1. change of overall or general climate in long-term 2. changes of some climatic elements such as rainfall, temperature, winds etc. in short term.

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5 Climate changes Like many parts of the world, Sri Lanka also experiences climate changes in terms of short term variations. During the last 3 decades, remarkable changes in rainfall and temperature, especially in the Dry region were evident. By 1960 the mean annual rainfall in the Dry Zone recorded as 1750mm. By 2002 it decreased to 1500mm. During , annual rainfall decreased by about 144 mm or 7% compared to that of period.

6 Rainfall -changes In the case of rainfall intensity, (the amount receives per rainy time) presently ( ) has increased resulting in irregular abnormal water availabilities; for instance; higher intensity caused floods and extreme low intensity resulted dry spells or droughts. During Floods and 7 dry spells and 2 droughts occurred Low year-round rainfall but with high intensity, resulted in an uneven distribution of water availability throughout the year. For example. Few months water surplus. A long periodwater shortage Furthermore, the monsoons, the prime source of water for this region characterized by remarkable variations.

7 The normal onset of NE monsoon records in December-January. But recently it has shifted to February or March. This caused upset of agricultural activities which are highly dependent on stored surface water (tanks) and ground water in some areas.

8 Temperature -changes During , the country s mean air temperature increased by about C 0 per year furthermore, higher evaporation together with prevailing winds caused rapid loss of water from the surface mean evaporation 3.6mm/day mm/day As a result, the ground water table that is the prime source of the people s domestic water use has further downed.

9 Area in the Dry season

10 Ground water Traditionally, in the near past, rural communities who lived in this region used ground water for drinking, sanitation, animal husbandry and small farming. Shallow dug holes were common Ground water table characterized by weathered gneiss rock formation. Its mean depth is meters. Deep ground water aquifer in this region is characterized by higher concentration of fluoride (6-8 mg/liter. PH 7.6, hardness 688ppm, chloride 242ppm. In drinking water taken from deep wells, fluoride concentration is about ppm.it is a level of long-term harmful to the human health.

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13 Changes in ground water use Problems. Shallow open wells rapidly go dry within a short period after rains Due to higher constructing cost of deep wells, people have to limit the use of permanent wells. Water in deep wells becoming unsuitable for drinking Trends In 1960, more than 60% people used ground water, drawn from shallow wells by 1990, it reduced to 40% By 2001 it declined to 32% In 2010 it was 23%

14 Decline of Ground water use Data from domestic well investigation Year 1970 Year 2008 Village No of householders No of shallow wells No of deep wells No of householders no of shallow wells No of deep wells

15 Groundwater level fluctuation Year 1970 Mean water level from surface to the water body (m) Year 2010 Village Wet season Dry season Wet season Dry season

16 Surface water Limited number of seasonal streams in this region are characterized by two hydraulic aspects; 1. Their water carrying capacities and discharge rates have apparently decreased by about 40% of their original capacities 2.The time that water remains in these streams is limited to one or two month of the year resulting in a greater part of the year remaining dried. 3.Man-made reservoirs (small tanks) are not capable to provide adequate water for both domestic and agricultural needs. 4.Low rainfall caused less water availability during the last 10 years 5. Higher evaporation caused rapid loss of water from the storages.

17 A dried-up tank

18 The long travelling distance to the streams from the people s residential sites has further restricted to access these water resources. Thus both ground water and surface water resources are now being under malfunction.

19 People s adaptation to the water scarcity 2 aspects 1. Changes in water utilization practices and methods 2.Changes of social behavior and attitudes on water 3.Long practiced paddy cultivation under small tanks has been changed to commercial crops and vegetable cultivation in small scale plots 4.Water taken from tanks for domestic uses has changed to the use of ground water drawn from wells in valley bottoms

20 Past 1900s Changes in water use 1960s Present 2009 Use source method Use Source Method Use Source Method Agricultur e Tank Gravity flow - Irrigation Agricultur e Tank wells Gravity flow Irrigation Drawing Agricultur e wells Pumping Drinking & sanitatio n Tank Ponds Streams Fetching with pots Direct use Dire Drinking & sanitation Open wells Drawn Drinking and sanitation Rainwater wells Roof rain water Pumping Bathing Tank Direct use Bathing Stream direct Bathing wells Drawing Animal husbandr y Cottage industries Tank Ponds Direct use Direct use Animal husbandry Tank Direct use Cottage industries Tank Stream Stream direct Drawn. pumping Animal husbandr y Cottage industries Tank Wells Direct Pumping

21 By 2007 a little number of public wells instead of individual wells came into common in villages. Individual wells in home gardens were abandoned due to lack of water One or two public wells were built by village community organizations By 2009 most of these public wells had been abandoned due to bad quality of water

22 Attitude changes Traditional irrigation tank systems are not further useful because water at sufficient level cannot be impounded throughout the year due to lack of rainfall. Tank man relationship has been collapsed Home gardening with rainwater is economically more profitable than rice cultivation traditional agricultural activities are being commercialized Well water is not quality for drinking a good awareness and understanding on water quality Rainwater or pipe born water can be accepted inclined towards the modern technology For bathing, storage water in traditional tanks is still accepted giving priority for bathing

23 Dry Zone village landscape, settlement transformation and water resources

24 Rain water harvesting systems Under these situations in 2005, government introduced RRWHS for these communities RRWHS is a system of catching rainwater where it falls on rooftop of the houses/buildings.

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31 People s priority on water sources before introducing the RWH Source Priority 1 (% households) Open wells 60% Tube wells 12% Rivers 11% Reservoirs 10%

32 People s priority at the demonstration stage Source Priority 1 (% household) Open wells 52% Tube wells 8% Rivers 9% Reserviors 8% RWH 23%

33 People s response to the initiation of RWHS 1 st stage People accepted No of establishment Response (perception) at the final stage (no of households) 30% 12 5 Excellent (full satisfied ) 4- Good (satisfied) 3- Bad( not satisfied) 2 nd stage 54% excellent 4- Good 2- Bad 3 rd stage 71% excellence 6- Good 2 Bad

34 Their views are summarized as follows Water quantity that could be collected by the roofs is sufficient for three months for an average family comprised 4 members. It is not adequate for a long dry period that they normally experiences about 6 months. Water stored in collecting tank is good for domestic uses and drinking. Water comes from roof is often polluted with bird droppings and dead insects added from the roof. These material disturbs the water enter the storing tank. A suitable method to avoid this is needed to be introduced.

35 Most people do not have houses equipped with suitable (permanent) roofs for rainwater colleting Thus they need help from any authority to build permanent roofs

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37 People s perception- reasons for drinking /not drinking Reasons for drinking Long distance to the nearest water sources. 22% Easy access of water 8% Quality is better than ground water 18% Cleanliness 4% Hygienic and healthy 3% Water in open wells go rapidly dry 45%

38 Reasons for not drinking Unclean roof surface 12% Lack of tank cover 79% Unusual taste like cement 9% It is understood that the people s incline to the rainwater harvesting method has been caused by climatic factors other than the social factors. Most people prefer rain water because of the scarcity of surface and ground water resources and difficulty to access them. RWH system in this region is further possible to be developed as a solution for drinking & sanitation problems caused by ongoing climatic changes.

39 Remark The early section of this research was based upon jointly work done with Thomas S. Soerens, Associate professor, Department of Civil Engineering, University of Arkansas supported by the National Science Foundation under Grant No

40 Thank you