Historically, economic crises have triggered the global policy of transferring the management of irrigation systems to water users associations. The impact of these transfers has been very complex and recent studies have shown that the outcomes vary from region to region, and are diverse even within a single country. The present study looks at 16 irrigation ditches in Colombia, where management was transferred from the Colombian government to water users associations. Some examples show an improvement in organizational stability, following the transfer of management, while others demonstrate a deterioration. A conceptual framework is presented, for the establishment of a sustainable management policy, based on an inter-relationship between the community, the environment and science and technology. For an effective implementation of the framework, the role of government, water users associations and farmers are considered to be the key elements, and it is believed that an effective integration of these players contributes to successful and sustainable management. The water users organization needs to follow an integral and participatory management approach, enlarging its span of action beyond mere operation activities, into the area of improvement of the standard of living of farmers. Encouraging the adoption of irrigated agriculture under criteria of sustainability, profitability, competitiveness, equity and multi-functionality is the way forward. The RUT Irrigation District is one of the most progressive irrigation districts in Colombia, and it is here that the conceptual framework has been intensively analyzed and evaluated.

This volume in the Fundamentals for the Water and Wastewater Main Operator series covers the basics of piping and valves in water and wastewater plants, including details on fittings, strainers, filters, traps and control systems. The book explains how pipes and valves are used to feed materials (e.g., chemicals) into influents and effluents and also siphon off unwanted liquid and gaseous byproduct. Also covered is how pipes are developed into systems and subsystems and coordinated into a plant-wide functioning unit.