Water Management Practices and Climate Change ...

Mainstreaming Climate Change Adaptations into Developmental Planning Water Management Practices and Climate Change Adaptation: South Asian Experiences S. Pathmarajah

Water Management Practices and Climate Change Adaptation: South Asian Experiences S. Pathmarajah1 The views expressed in this paper are the views of the authors and do not necessarily reflect the views or policies of ADBI, the Asian Development Bank (ADB), its Board of Directors, or the governments they represent. ADBI does not guarantee the accuracy of the data included in this paper and accepts no responsibility for any consequences of their use. Terminology used may not necessarily be consistent with ADB official terms. Introduction I begin this article with an interesting quote that I have notices on the Internet… “…. awareness on climate change may be an issue in Sri Lanka, but here in the UK, its not. There’s almost too much of awareness. If I get a penny every time they say ‘climate change’ I ‘ll be a rich man……” Due to the international efforts, there is an increasing awareness on “climate change” among the scientists and the policy makers even in South Asia now. Sri Lanka has ratified the United Nations Framework Convention on Climate Change (UNFCCC) in 1994 and taken the first Green house Gas Inventory in 1995. Also it has established a Centre for Climate Change Studies (CCCS) at the Department of Meteorology which regularly monitor various climatic parameters including the temperature and the rainfall through a well established island wide network of monitoring facilities. It has ratified the Kyoto Protocol on 3rd September 2002. Subsequently, two national Clean Development Mechanism (CDM) study centres were established at two leading Universities. Being a small island nation, Sri Lanka falls into the UNFCCC and IPCC’s category of ‘vulnerable’ small island nations under serious threat from various climate change impacts, such as sea level rise and severe floods and droughts. These threats could have significant negative consequences on various sectors within Sri Lanka. Sri Lanka’s dry zone agricultural output will decline significantly in the next 20 to 30 years because of reduced rainfall and hotter weather. Despite the early warnings there is little readiness by poor countries. Every year, poor people in Sri Lanka, mainly farmers and fishermen, face the effects of climate change which are causing droughts, floods and storms. In the last six years droughts have hit Hambantota in 2001 and Anuradhapura and Kurunegala districts in 2004, affecting farmers and residents in general. Rich cities are ready with their elaborate flood barriers and climate defense systems (SUNG-NO NIGGOL SEO, et al.).

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Faculty of Agriculture, University of Peradeniya

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Effect of Climate Change on Water Resources According to the International Water Management Institute (IWMI), one-third of the developing world will face severe water shortages in the twenty-first century even though large amounts of water will continue to annually flood out to sea from water-scarce regions. The problem is that the sporadic, spatial and temporal distribution of precipitation rarely coincides with demand. Whether the demand is for natural processes or human needs, the only way water supply can match demand is through storage. There are four major ways of storing water in the soil profile, in underground aquifers, in small reservoirs, and in large reservoirs behind large dams (Keller, et al., 2000). If climate change as a result of global warming manifests, the need for freshwater storage will become even more acute. Increasing storage through a combination of groundwater and large and small surface water facilities is critical to meeting the water of the twenty-first century. This is especially so in monsoonal Asia and the developing countries in the tropics and semi-tropics. Strategies The 4th report published by the Intergovernmental Panel on Climate Change (IPCC) in 2007 suggests that it be as important to promote “adaptation” to the impacts of global warming as to promote “mitigation” since global warming “mitigation” centered around the reduction of greenhouse gases has limitations, and global warming impacts would continue over centuries even when “mitigation” is implemented. Adaptation strategies to avoid drought risk caused by climate change should be considered to be an emerging priority issue in comprehensive water resources management. According to the UN/ISDR - UN Intl Strategy for Disaster Reduction Sec (15 January 2009), any physical construction to reduce or avoid possible impacts of hazards, or application of engineering techniques to achieve hazard-resistance and resilience in structures or systems is defined as structural measure, and any measure not involving physical construction that uses knowledge, practice or agreement to reduce risks and impacts, in particular through policies and laws, public awareness raising, training and education is non-structural measure. Climate change will compound existing food insecurity and vulnerability patterns. Vulnerability patterns will be modified by climate change. Small-scale farming systems, both rainfed and minor tank irrigated are particularly vulnerable to climate change Communities must prepare themselves for the possibility of food shortages and make appropriate use of resources to protect their livelihoods as well as lives and property. Technical adaptation measures range from temporal and spatial variations in production systems (e.g. adjusting planting or fishing dates, rotations, multiple cropping/species diversification, crop-livestock pisciculture systems, agroforestry) to confer better protection against temperature changes, changing rainfall variability and patterns, salinization though sea level rise, and pest attacks - to investing in soil, water and biodiversity conservation and development (e.g. building soil biomass, restoring degraded lands, rehabilitating rangelands, harvesting and recycling water, planting trees, developing adapted cultivars and breeds, protecting aquatic ecosystems) in order to maintain long-term productivity. Adaptation measures also include establishing disaster risk management plans and risk transfer mechanisms, such as crop insurance and diversified livelihood systems.

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Conventional approaches to climate change adaptation range from water conservation and efficient use to new operational technologies. Dams and reservoirs are still considered as the most effective structural means of risk management. But we need to start thinking of the environment as infrastructure for adaptation as well. Both these measures cannot be considered in isolation. There are existing structures around which non-structural aspects are established. Therefore, adoption to climate change will require a holistic approach. Water resource adoption strategy for climate change in Sri Lanka as observed byAkiko Yamane, 2003 are as follows: 1. 2. 3. 4. 5. 6. 7.

Encourage minor storage water reservoirs Investigate feasibility of trans-basin diversion schemes Conserve seasonal water Rehabilitate irrigation water tanks networks Promote micro-watershed management Prepare groundwater extraction regulation policy Introduce permit/monitoring systems for ground water extraction and water quality assessment in vulnerable areas

Climate change related food security in Sri Lanka is designed around sustaining the dry zone agriculture where ancient minor irrigation tanks play a vital role. The small tank system has contributed to food production and environmental conservation with a multitude of social benefits to the villagers living in the dry zone. These tanks form a series of water bodies along small water courses in cascading system. They have been designed so that water is repeatedly put into use to counteract irregularities of rainfall, non availability of large catchment areas and the difficulty in constructing larger reservoirs. There are about 12,500 small tanks scattered throughout the dry zone and reports indicated that they have an irrigation potential of about 100,000 ha ( Gunasena, 2000). The main constraint to the development of minor tanks has been the change that took place from their traditional management, which overlooked the beneficiaries, the farmers. The management system has been changing over the years with scantiest regard to the farmers living under the minor irrigation schemes. The attempt to improve the cropping under these tanks too has been unsuccessful due to insufficient storage, lack of labour and marketing facilities. The preoccupation of farmers in upland chena cultivation has dissuaded them from adopting crop diversification. However small tanks are highly relevant to the rural development programmes, considering their agricultural, socio-economic and environmental benefits. Modernizing the agricultural production systems within a cascade will have expanded potential ensuring their economic, social and environmental sustainability. Conjunctive use of surface water and groundwater has been initiated within the minor tank command areas in a haphazard manner. It is noted that agro-wells (large diameter wells) are constructed under different to small tank command areas without considering the hydrological basis of the cascade system. The agro-well development has to be undertaken carefully not to the exploit the shallow ground water table of the cascade system as it could leas to disastrous economic and environmental consequences. The need to have clear policies based on technical feasibility to utilize the small tanks on sustainable basis. The seepage and percolation “losses” from small tanks in Sri Lanka account for 20 percent of reservoir volume against 5 percent of reservoir volume in large dams. These small reservoirs can act as percolation tanks, recharging aquifers and retarding runoff. In fact, in

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India, small reservoirs that have high percolation rates, “percolation tanks”, are often preferred because of their contribution to groundwater recharge. Perhaps the greatest threat facing existing reservoirs, both large and small, is sedimentation. While highly variable, it is estimated that 1 percent of the total global freshwater surface storage capacity is lost each year. “Dahasak Vew” (Tank Rehabilitation) – This is a flagship project highlighted in the Economic Policy Framework of the government. The project recognizes the augmentation of water supply in basins, where water stress exists, by harnessing the rain water and storing it in existing and abandoned village tank systems. Under the project, rehabilitation of 10,000 minor tanks is proposed. In addition, diversion of perennial water by means of anicuts to farm lands through supply canals for cultivation in the upcountry region is also recognized. It is proposed to develop identified tanks in an integrated manner (Department of National Planning, Ministry of Finance and Planning, Sri Lanka). Apart from the Government’s initiatives, minor tank rehabilitation and agro-well promotion programs have been undertaken in Sri Lanka by the International NGOs during the past 20 years. Though the objective was not to adapt to climate change it had an element of sustainable livelihood under extreme weather conditions. In southern Sri Lanka, construction and linking of a large storage reservoir at Lunugamvehera with five small, existing, cascading reservoirs resulted in a 400 percent increase in crop production. In fact, cascading small reservoirs can significantly increase crop water use by capturing drainage, return flow, and surpluses from upstream reservoirs. Complementarities also occur where surface storage, particularly in the form of microreservoirs, retards runoff and enhances groundwater recharge. Many storage reservoirs, which were previously used as irrigation tanks in the arid and semiarid tracts of India, have now been converted to recharge ponds, and tube-wells have taken the place of irrigation canals. These successful experiments indicate that combinations of big and small reservoirs along with effective aquifer management can provide efficient solutions for conserving water and increasing its productivity. Hitherto, this concept has not been effectively put into practice from the planning stage, although it has been practiced in many areas of the world. With water becoming scarce, use of such integrated planning for conserving water could lead to higher water productivity while maintaining environmental and ecological balance (Andrew Keller, et al., 2000). Combinations of small and large storage and surface water and groundwater recharge are generally the best systems where they are feasible. In monsoonal Asia, research and development are needed on how to manage water under monsoonal conditions. Conclusions Structural and non-structural measures have to be adapted at the same time to cope with the anticipated impact of climate change. Investment on climate change related adaption measures are still at its infantry in the South Asia. The actions taken are the extension of responses to extreme flood and draught conditions that were encountered in the past. Climate change challenges the traditional assumption that past hydrological experience provides a good guide to future conditions. The consequences of climate change may alter the reliability of current water management systems and water-related infrastructure. Lack of adequate information and financial constraints are the major issues.

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Awareness on climate change and its impact on the general population are yet to be raised. As the climate change related disasters are unpredictable extension programmes have to be designed carefully to address these issues. To discuss adaptation strategies, the impacts imposed on society and economy by waterrelated disasters due to climate change should be presented to the general public and related organizations in an easy-to-understand form. The selection of appropriate adaptation strategies will be possible only after people sufficiently understand those vulnerabilities. It is important for the national government to take the initiative in developing coping strategies at the basin level, including role-sharing among related organizations. Biotechnology should aim at increasing crop yields while reducing the water requirement and developing crops that are less dependent on water. Management practices such as altering the dates of planting, spacing and input management, alternate crops or cultivars, change in irrigational practices, etc. should be experimented. Adaptation to environmental change in the form of social cover such as crop insurance, subsidies and pricing policies related to water and energy are essential. Policies such as financial compensation/incentive for green manuring, recycling waste water and solid wastes in agriculture should be evolved. Alternative livelihoods that are less dependant on agriculture have to be tried. It is important to promote “adaptation” to the impacts of global warming as to promote mitigation” since global warming “mitigation” centered around the reduction of greenhouse gases has limitations, and global warming impacts would continue over centuries even when “mitigation” is implemented. References Akiko Yamane. 2003. Rethinking vulnerability to climate change in Sri Lanka. 9th International conference on Sri Lanka Studies, 28th – 30th November 2003, Matara, Sri Lanka. Gunasena, H. P. M. 2000. Food Security and Small Tank Systems in Sri Lanka: Proceedings of the Workshop Organized by the Working Committee on Agricultural Science & Forestry, NSF, Sri Lank. IPCC Technical Paper on Climate Change and Water. 2008. Keller, Andrew; Sakthivadivel, R.; Seckler, David. 2000. Water scarcity and the role of storage in development. Colombo Sri Lanka: International Water Management Institute (IWMI), vii, 20p. (Research report 39). Sung-No Niggol Seo, Robert Mendelsohn and Mohan Munasinghe. Climate change and agriculture in Sri Lanka: a Ricardian valuation.

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