Technical, socio economic and institutional context of small tanks in Sri Lanka

Abstract

Small tanks in Sri Lanka are those having an irrigated command area up to 80 ha ( I ha = 2.47 acres). They must be treated as single systems as most of these individual tanks meet irrigation water requirements of one village or one command area. Small tanks consist of a tank bund, sluice or sluices, a spillway and main field channels. There are 30000 small tanks in Sri Lanka and 48 percent are abandoned. 18 percent is covered by the command area under small tanks. Three-fold land use system is traditionally practiced in small tank villages. They are gangoda or home gardening, chena or shifting cultivation and paddy cultivation. Paddy is grown on land below the tank bund in the command area of the small tank. In small tank villages, smallholders produce paddy mainly for home consumption. Total annual household cash income from selling paddy was only 11 percent. There are two categories of land in the command area called puranawela (beginning of the land area) akkarawela (actual land area). Paddy cultivation in small tank villages is quite modernized. All the activities are mechanized and farmers use improved paddy varieties. Three major social groups live in small tank areas. Majority of them are Tamils and Muslims living in the northern and eastern provinces. In the other provinces the majority are Sinhalese. Karma meetings (growing season) are organized by farmers' associations. The kanna meeting is a mechanism through which the cultivator can reach a general consensus on fixing working dates, selecting paddy varieties, deciding on the extent of command area to be irrigated, preparing a calendar for cultivation, preparing an irrigation schedule for the issue of water, putting fences around the command area and putting up of watch huts and others. Land erosion and silt sedimentation in tank, vegetation cover on the tank, land fragmentation, insufficient water for growing two seasons and elephant attacks are the major problems in small tank villages.