Abstract:
In the dry zone of Sri Lanka, where agriculture is the main livelihood, both farmers and water
managers target the best use of water. System His an area that had been developed for irrigated agriculture
using diversions from the River Mahaweli. Study of water use practices was carried out in two irrigation
schemes where farmers cultivate the same crop in one-hectare allotments under the support and supervision
of the same regional authority. Records of water use and agriculture are not well maintained. Using field
visits, discussions with farmers, and meetings with officials were used to fill data gaps and three water issue
scenarios were compared. Results of each scheme varied because water release and rotation practices for
crop growth are quite different from each other, canal efficiency assumptions are different, land preparation,
water use and quantity are dissimilar, and water releases do not consider much about growth stages. The
study indicated that use of challenging water issues considering co-ordinated and rational grouping of
canals could lead to a saving of 10-30 em of water per unit area. A discussion of the need for a critical
evaluation of guidelines and the present practice of cultivation is included