The Human Impacts Database

A collection of useful numbers for quantifying the impacts of the human presence on Earth.


Volume of water in rivers that are not free-flowing

WaterFlowing Water Fragmentation

This quantity is a single measurement of the quantity at a given point in time (None).

Value: ≈ 5.64 × 1011 m3
HuID: 61661
Summary: This value corresponds to the global river water volume that is contained in rivers that fall below the connectivity threshold required to classify them as free-flowing. The total volume of water contained in rivers indexed in this study is ≈ 1.17 x 1012 m3.
Method: The source dataset is comprised of a geometric network of river, their associated attributes, and connectivity metrics. The dataset considers only global rivers with upstream catchment areas greater than 10 km2 or discharge volumes greater than 0.1 m3 per second. Disruption factors indexed in this dataset are fragmentation, flow regulation, sediment trapping, water consumption, and infrastructure development. Shown here is the sum of river volume contained in ocean-connected rivers that fall above the connectivity threshold required to classify them as free-flowing. An assessment of uncertainty is not made but the exact value depends on the cutoff used to define a “free-flowing” river. See the source publication, dataset, and dataset documentation for details.
Source: Grill, G., Lehner, B., Thieme, M. et al. Mapping the world's free-flowing rivers. Nature (2019)
Dataset: Summary of the volume, length, and discharge of free-flowing and non-free-flowing rivers (Grill_et_al_river_fragmentation_summary.csv)
global resolution
regional resolution
Original Data License: Nature Reuse and Permissions Policy
Added By: nsarai