He addresses only the seasonal and annual performance of the water delivery system in this paper. Variability indicators examine the uniformity of flow and intensity and the reliability of the flow. The third set of indicators looks at operational efficiency. The findings of the study underline the importance of setting clear targets for each season. The annual volume of water farmers expect to be delivered is not realistic.
Insufficient water is available in the reservoir to meet all of the targets.
Realized supply is 80 percent of targeted supply, but supply fluctuates considerably over the year. This figure sounds good until one realizes that distribution is extremely inequitable. A large part of the area is irrigated twice when it is only supposed to be irrigated once, while half of the area receives no irrigation water at all. Jurriens concludes that farmers' wishes and practices are often in conflict with the design of the system and its capabilities. Carrying out the performance analysis seems to be a useful exercise for understanding scheme characteristics and management problems.