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waterlogged, where the groundwater table has risen to less than one meter below the soilsurface. Waterlogged areas are vulnerable to salinization, and the impact on surrounding areascan be quite severe, causing the loss of both wet and dry seasonal crops. Studies conductedprior to the Mahaweli irrigation project, have shown that about 5% of the paddy fields wereaffected due to salinity, mostly emerging from underground reserves (Sikurajapathy et al., 1983& Handawala, 1983). More resent results by Thiruchelvam and Pathmarajah (1999), indicatethat around 23% of the farmers were operating under high salinity conditions, and that theaffected land had increased to 7% of the total farming area. These farmers are experiencingcrop damage caused by salinization, and in certain areas the damage may accounts for asmuch as 25% of the yield. The high salinity levels can be ascribed to the dry climate, poordrainage practices, use of drainage water for irrigation and inefficient irrigation management(Thiruchelvam and Pathmarajah, 1999).In addition to crop loss, other potential negative impacts following salinization involve ecosystemdegradation, diminished surface water quality, and increased public health risk.Farmers owning affected fields have adopted mitigation methods, such as organic matterapplication, flushing, use of ameliorates, and increased drainage. The financial gain fromreduced salinity can be as high as Rs10 per kg of rice. Other studies have shown that the mostviable and cost effective approach to salinity control is adequate surface drainage,(Sumanaratne and Abegunarwardena, 1993 & Herath, 1985). Installing drainage systems willleach out soluble salts, is another solution. Per hectare, an adequate system would requireapproximately 8 plot drains (tertiary), 4 field drains (secondary) and 2 field drainage channels(Thiruchelvam and Pathmarajah, 1999).According to MASL, the drainage canals had originally been laid out between every two fields.Those were sufficient to drain the whole system of excess water. However, farmers reportedlyclear only the irrigation field canal, and not the drainage canal. Furthermore, MASL’s operationand maintenance activities have so far mainly focused on the irrigation canals. In some places,even the field drainage canals are being cultivated! As a result water logging and salinizationhave become problems in these areas.In Thiruchelvam and Pathmarajah (1999), it is expressed that there is considerable scope forgrowing trees and shrubs to deplete the groundwater table, and reduce the salt problem underirrigated conditions. Biological drainage using salt tolerant and fast growing tree species is lessexpensive than a capital-intensive technological solution. Farmers may justify tree planting oneconomic grounds. Therefore, income-generating trees such as banana, mango and fastgrowing fuel-wood species like Eucalyptis, Ipil Ipil, and Casuarina could be planted in tankbunds, canal areas and in other vacant irrigated areas.18The Value of Traditional Water Schemes:Small Tanks in the Kala Oya Basin, Sri Lanka
NATIONAL FRAMEWORKS:Legal and institutional context to waterresources planning and managementSince the creation of the Irrigation Department in 1900, and particularly since the 1930s, theanthropocentric use of water has been driven by national, centrally conceived plans, as incontrast to the village-level focus of indigenous water regimes, and early colonial strategies. Theengine driving this centralization was a growing desire to maximize food production, asmeasured in terms of national output. For such designs of large scale agriculture, investments invillage-level infrastructure were deemed inadequate, and planning was shifted towards the IDand away from the Government Agent who hitherto had been responsible for Provincial andvillage level planning.There are several laws and regulations that deal with water management• Mahaweli Authority of Sri Lanka Act, No. 23 of 1979• Irrigation Ordinance, No. 32 of 1946• Water Resources Board Act, No. 29 of 1964•National Water Supply and Drainage Board Act, No. 2 of 1974 1• Flood Protection Ordinance, No. 4 of 1924• National Environmental Act, No 56 of 1980 2• National Environmental (Procedure for approval of projects) Regulations, No. 1 of 1993• Gazette Extra-Ordinary No. 772/22 of 1993• Gazette Extra-Ordinary No. 1104/22 of 1999• Gazette Extra-Ordinary No. 859/14 of 1995• Gazette Extra-Ordinary No. 978/13 of 1997Several other laws provide for the direct conservation of wetlands as protected areas,3 butthese (apart from the National Environmental Act) will not be considered in this study, since thestudy’s focus is on how wetland conservation can be promoted, in legal frameworks of the nonconservationsectors.LegislationMahaweli Authority of Sri Lanka Act, No. 23 of 1979This was enacted to establish the MASL, (the Authority) for the purpose of implementing thelargest water management projects undertaken in Sri Lanka – the Mahaweli Development1 Amended by National Water Supply and Drainage Board (Amendment) Act, No. 13 of 19922 Amended by Acts Nos. 56 of 1988 and 53 of 20003 Fauna and Flora Protection Ordinance, No. 2 of 1937 (as amended by Acts Nos. 44 of 1964, 1 of 1970 and 49 of 1993); Fisheries andAquatic Resources Act, No. 2 of 1996; and the National Environmental Act, No 56 of 1980The Value of Traditional Water Schemes:Small Tanks in the Kala Oya Basin, Sri Lanka19
Page 1: The Value ofTraditional Water Schem
Page 5 and 6: EXECUTIVE SUMMARYSri Lanka has one
Page 7 and 8: TABLE OF CONTENTSBACKGROUND .......
Page 9: BACKGROUNDThe project “Integratin
Page 12 and 13: also used to set up the planning un
Page 15 and 16: THE SITE:Water, ecology andsocio-ec
Page 17 and 18: Bahu the 1st, the epic hero of the
Page 19 and 20: The Rajangana sub-catchment of the
Page 21 and 22: Table 3: Land use in the Kala Oya B
Page 23 and 24: out by MASL in year 2001 covering 2
Page 25: and tenants give an agreed portion
Page 29 and 30: ecosystems and other natural system
Page 31 and 32: the Ministry of Finance. Projects n
Page 33: nature of these features, seriously
Page 36 and 37: of benefits, is greater than the to
Page 38 and 39: needs, on the other.Pricing methods
Page 40 and 41: agricultural purposes, as water is
Page 43 and 44: DIRECT VALUES:Use of water and wetl
Page 45 and 46: when there is not enough water for
Page 47 and 48: Around 86 animals are on the tank r
Page 49: Summary of valuesTable 18: Economic
Page 52 and 53: Identifying and assessing the funct
Page 54 and 55: growth can hurt the ecosystem in tw
Page 56 and 57: water hyacinth, which is and alien
Page 58 and 59: ii)Raise the level of the spill in
Page 60 and 61: Impacts of alternative scenariosDom
Page 62 and 63: Table 23: Qualitative estimates of
Page 65 and 66: CascadesOTHER IMPORTANT BASIN VALUE
Page 67 and 68: 2-3km along the river towards inlan
Page 69 and 70: of 80 Kg/animal, and a recovery rat
Page 71 and 72: Monetary resources for tank rehabil
Page 73 and 74: BIBLIOGRAPHYBalasubramanian, R. and
Page 75 and 76: ANNEX:Assumptions used in scenario

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