The Integrative Dam Assessment Modeling tool, or IDAM, uses an interdisciplinary approach to simultaneously evaluate the distribution of biophysical, socio-economic and geopolitical impacts of dams, according to one of the model’s creators, Bryan Tilt, an associate professor of anthropology at Oregon State University.

The model was designed as a decision-support tool that policy makers can use to understand holistically the impacts, costs and benefits of building a dam in any area. On 27 July researchers at Oregon State University who developed the model will present the tool in Washington, DC, to a group of policy-makers, government agencies and environmental organizations from the US, China and Southeast Asia.

The dam assessment tool measures the costs associated with a proposed dam development project and also measures the possible benefits. Each of the diagrams in the tool consists of 27 individual indicators of the effects of dam construction, divided into socioeconomic, geopolitical and biophysical themes. For example, factors such as habitat restoration costs can be weighed, along with loss of income to local people and access to clean drinking water.

“When you put up a dam, it affects whole ecosystems and whole communities,” Tilt said. “No other measurement tool can allow for so many variables, and allow the user to weigh what factors they view as most important.”

Tilt said the impetus for this dam modeling project followed the publication of the World Commission on Dams in 2000, which called for more equitable and sustainable decision-making with respect to large dams. In 2007, the National Science Foundation funded the research by OSU and its collaborators to develop and test this dam assessment tool.

Numerous studies modeling real dams in China helped the researchers refine the tool, which they believe will help policy-makers make more informed decisions about building dams.