New global database on dams and reservoirs could transform water management

A database developed by the Global Dam Watch (GDW) consortium is poised to transform the world’s understanding of dams and reservoirs.

Coordinated and led by members of a research laboratory at McGill University, the database integrates existing global datasets to provide the most comprehensive resource for large-scale analyzes to date. The research is published in the journal Scientific data.

River barriers, ranging from large dams to small locks, weirs or dams, play an essential role in water supply, flood control, hydroelectric power generation and navigation, but also have ecological consequences, including fragmentation of river ecosystems and disruption of sediment flow. Using the GDW database, researchers and policymakers can perform large-scale analyzes of these tradeoffs, leading to more sustainable and better-informed water management practices.

“The breadth and depth of the data will facilitate analyzes that were previously impossible, helping to strike a balance between exploiting water resources for human use and protecting the ecosystems that depend on these rivers,” said Bernhard Lehner, associate professor in the Department of Environmental Sciences at McGill. Geography, who has overseen the database project in his research laboratory for the past three years.

Of the 41,145 dams listed in the GDW database, 450 are in Canada, and more than a third of them are built primarily for hydroelectric power generation. Although these dams represent only one percent of the database’s records, they impound some of the world’s largest reservoirs and provide approximately 11 percent of the world’s total water storage capacity, highlighting the important role of Canada in the management of the planet’s fresh water.

“This database represents a major step forward towards a comprehensive and consistent global database on river barriers and reservoirs. A wide range of hydrological and water resources analyzes are now possible, with major implications for water management. water resources and conservation of freshwater systems – the lifeblood of humans and nature across the world,” said Michele Thieme, deputy director of freshwater at the World Wide Fund for Nature.

The 41,145 barrier locations in version 1.0 of the GDW database are associated with 35,295 reservoirs, creating a cumulative storage capacity of 7,420 km³ and a new surface water area of ​​304,600 km². Compiling data also allows researchers, policymakers and environmental advocates to assess the socio-economic and environmental costs and benefits of dams with unprecedented clarity.

“The Global Dam Watch (GDW) Database consolidates the world’s largest open-access global datasets into a unified, comprehensive resource with consistent information on dam attributes. Along with other tools available at www.globaldamwatch.org, its publication aims to enable the community to improve our understanding of the socio-economic and environmental costs and benefits of dams,” said Mark Mulligan, professor of physical and environmental geography. at King’s College London and co-leader of the GDW consortium.

The project allowed a diverse team of McGill undergraduate and graduate students to gain valuable hands-on experience. many students contributed significantly to the research and data collection processes.