Integrated Water Management (IWRM) is the practice of making decisions and taking actions while considering multiple viewpoints of how water should be managed (www.waterencyclopedia.com, 2010). IWRM has been defined by the Technical Committee of the Global Water Partnership (GWP) as "a process which promotes the coordinated development and management of water, land and related resources, in order to maximize the resultant economic and social welfare in an equitable manner without compromising the sustainability of vital ecosystems.
IWRM is a systematic process for the sustainable development, allocation and monitoring of water resource use in the context of social, economic and environmental objectives. IWRM is based on the understanding that water resources are an integral component of the ecosystem, a natural resource, and a social and economic good. Typical components of this framework are shown in the figure below.
IWRM is a way to plan for and manage water resources with more than the single water supplier in mind but instead the view of cause and effect relationships throughout a region. IBM assisted Northern California with an Integrated Water Resources Management Plan and provided the following graphic on their webpage as a way to demonstrate possible components of a regional water system.
An example of a typical IWRM project is depicted in the following figure, which is based on real world modeling examples. In this example, surface water supplies are exported from a natural river system which happens to be affected by external human influences and the natural elements. Actions taken by the system can also impact external human actions outside the system. Each structural component is coupled with aspects of viewpoints, policy, and economics. Other influences such as recreation and the environment could also play a significant role within the system simulation.
IWRM should be viewed as a process rather a one-shot approach -one that is long-term and forward-moving but iterative rather than linear in nature. This iterative approach requires a tool that is easy to customize and refine based on changing needs. The following flow diagram shows a possible modeling scenario using this type of process.
