GeoICOLD, a georeferenced global dam and reservoir dataset based on the registry of the International Commission on Large Dams

Abstract:

Dams and reservoirs are ubiquitous across global river basins. Despite their social and environmental significance, our spatial inventory of global dams and reservoirs, even for the large ones, has been insufficient. One of the best available datasets, the World Register of Dams (WRD), was established by the International Commission on Large Dams (ICOLD). The most updated ICOLD-WRD documents more than 58,000 large dams, which are considered to be “complete” to the extent of contributions from willing nations and authorities. Although ICOLD-WRD provides more than 40 attributes (such as dam purpose, construction year, and reservoir storage capacity), the dam locations are, unfortunately, either not georeferenced or not yet accessible. Missing spatial coordinates has critically limited the application of ICOLD-WRD (such as in hydrological modelling and hydropower planning) despite the availability of other essential attributes. Here, by utilizing multi-source inventories and the Google Maps geocoding API, we present a new dataset GeoICOLD, which contains about 24,000 georeferenced large dams worldwide and their reservoir boundaries, each indexed by a unique identifier that also enables the retrieval of all 40+ proprietary attributes from ICOLD. GeoICOLD is essentially a georeferenced version of ICOLD-WRD, except that it was further supplemented by 1) GRanD for an improved inclusion of the largest dams and 2) high-resolution water maps for acquiring reservoir boundaries. For proprietary reasons, GeoICOLD does not release detailed ICOLD-WRD attributes; instead, it provides the ICOLD “international code” of each dam, through which users can acquire other attributes from the WRD website. Due to geocoding challenges, GeoICOLD located less than 50% of the ICOLD-WRD dams by number. However, these georeferenced locations were quality-assured, and after the supplementation from GRanD, GeoICOLD captures a total storage capacity of about 7500 km³ that is comparable to the full storage capacity of ICOLD-WRD.