2.1 Balance multiple uses through Integrated Water Resource Management

Key organisations :
International Commission on Irrigation and Drainage/French National Committee - Société du Canal de Provence, Food and Agriculture Organisation, International Water Resource Association, ICIWaRM, Murray Darling Basin Association, Global Water Partnership, US Army Corps of Engineers

The need to balance water uses arises when water resources do not meet the needs of all uses, including both human and environmental. This is the case, of course, where and when water is scarce. But the same need arises when the overall resource is abundant but subject to competition due for instance to quality or accessibility reasons. This situation may have several origins such as: increasing variability in surface water flows, declining groundwater quantity and/or quality, population growth and subsequent increase of the demand, inefficient hydraulic systems, governance and stakeholder issues, increasing recognition of ecosystem services water requirements and inequitable access to the resources, etc. In addition to physical water scarcity, economic water shortages occur where poverty limits planning and water distribution, as efforts necessary to control and withdraw the water, then to transport and store it, are wide-ranging in terms of investment, labor and energy, thus in cost.

The uses of water and the purposes of use are themselves very diverse, and the needs as regards to quantity and the quality are very different. It has also to be pointed out that the water withdrawn from lakes, rivers or aquifers returns totally or partly either to the atmospheric hydrological cycle or to the watershed, where it becomes again available to other users, but affected in time or in quality. In this complex context of growing competition for scarce water resources there is an absolute need for integrated management of these resources. This implies, in particular, identifying and recognizing decision criteria for the quantity and quality of water needed for each use and the value of water in each use.

Well managing water resources involves multiple level challenges that require dealing with a range of policy, institutional, and technical issues. Integrated Water Resource Management (IWRM) aims at considering together all the different uses of all water resources. Water allocations and management decisions consider the effects of each use on the others, and take in account overall social and economic goals, including the achievement of sustainable development. The essential purpose of IWRM is to manage water more efficiently (use less water, more value per drop, conserve) and effectively (delivery of reliable services, improved performance in each sector). Balancing Multiple Uses of Water (BMUW) is one of the key outcomes of IWRM, which focuses on solutions how to cope with the rising competition for water between multiple kinds of users and allocate water in ways that are equitable, efficient, and sustainable.

“Integrated Water Resources Management (IWRM) is a process that promotes the coordinated development and management of water, land and related resources in order to maximize economic and social welfare without compromising the sustainability of ecosystems and the environment” (GWP 2000 and 2004).

The challenge is to put forward concrete developments in terms of methods, tools and implementation. Completion of the PFA 2.1 Targets and Solutions including – governance and planning adoption of IWRM processes, development of international water use quantity, quantity and value frames of reference, validation of IWRM models and other tools, development of international recommendations for reliable water resources measurement and accounting and integration of all water uses and sources – will greatly improve management of water and other resources and contribute to economic development and other goals.