Challenge 1:
Historical Impact
Discovering past hydraulic infrastructure management and its impact on river discharge.
There is currently no single dataset that provides both the technical specifications of hydraulic infrastructure (e.g., dams, wells, water diversions) and information on its daily-to-monthly operations. As a result, human actions remain poorly represented in global hydrologic models (GHMs), limiting our ability to quantify their impact on river discharge.
To address this gap, Challenge 1 will reconstruct a time series dataset of operational decisions for all large hydraulic infrastructure, globally. These data will then be processed by a GHM to quantify the differential impact of human actions on rivers. The analysis is executed over the period 1950-2025.
Challenge 2:
Riverine Ecosystem Indicators
Linking HI management, hydrologic alterations, and the status of riverine ecosystems.
The impact of hydraulic infrastructure on river systems is not currently well understood. Challenge 2 will develop a model framework (REAMS-River Ecosystem Assessment Models) to compute five indicators of river health and biodiversity: hydrologic alteration, river fragmentation, sediment load, river temperature, and fish biodiversity.
This model framework will be used to derive a dynamic multi-criteria dataset of changing biophysical processes in the world’s rivers from 1950-2025. This dataset will provide a global overview of how changes in water and land use impacted river processes day-to-day and year-to-year.
Each of the five REAMS indicators will compute a naturalized baseline, modeled without the presence of hydraulic infrastructure, land use, and climate change; as well as for a historic scenario with the presence of these pressure factors. This will allow the Challenge to estimate where and how much current conditions in rivers deviate from natural conditions vs hydraulic infrastructure impacts.
Challenge 3
Exploring Uncertainty
Uncertainty characterization of DARE models and data products.
The development of DARE involves uncertainties including input datasets, model parameterizations, and the spatial and temporal limitations of observational data. To characterize these uncertainties, we will first validate our data and models against observed records and existing reanalysis datasets, following established best practices in uncertainty analysis. Building on this foundation, we will advance the methodological frontier in global hydrological modeling by quantifying uncertainty bounds to incorporate the limitations and gaps in observational data.
Challenge 4
Policy Impacts
Policy impacts through engagement.
To maximize the impact of this science and to improve its utility to decision
makers, managers and scientists, DARE’s team includes the World Wildlife Fund (WWF-US), an international NGO that has the ability to convene and engage directly with government, communities, corporations, scientists and financial institutions at national, regional, and global scales. This challenge will host stakeholder engagement meetings to gather input on refining DARE for applications at different scales and for different uses.
DARE’s chief output will be the Atlas.
The Atlas will house vectorized data (e.g., river reaches, infrastructure locations) and time series data (e.g., river discharge, dam operations). The core components of the atlas will consist of:
(1) a global dataset of hydraulic infrastructure management from 1950 to 2025 with daily-to-monthly resolution;
(2) daily river discharge for the period 1950-2025 with and without human influence;
(3) conditions of ecosystem indicators with daily (discharge alteration, temperature), monthly (sediment transport), and yearly (fish biodiversity, fragmentation) resolution;
(4) quantified uncertainty expressed through hundreds of scenario realizations that reflect uncertainty in both input data (e.g., land use change, climate forcings) and derived outputs (e.g., discharge, ecological indicators).
From these, a subset of scenarios will be selected to support communication and stakeholder engagement. By systematically capturing where, when, and what changes have occurred in river discharge and hydraulic infrastructure operations, DARE will establish a foundation for assessing the role of human interventions in shaping rivers. The atlas will also identify who the key actors are in driving these transformations and quantify their ecological consequences.
Finally, by uncovering how different human actions contributed to observed changes, it will offer critical insights into river ecosystem responses to socio-environmental pressures. Conceptually, DARE is a five-dimensional dataset: it combines three spatial dimensions with one historical temporal dimension (1950–2025) and one uncertainty dimension, representing confidence bounds around key variables and capturing the range of plausible past conditions across hundreds of scenarios.
DARE Project 