Page 9 - CIWA Water Data Revolution Overview Report

Water Data Revolution: Closing the data gap for transboundary water in Africa

sensing (RS) technology presents a valuable solution for addressing some of the key challenges
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associated with the limitations of in-situ data . RS can mitigate issues related to gaps in ground-
based observations by providing broad spatial coverage across regions, including areas where in-
situ data is limited or entirely absent. With continuous historical records, RS data offers consistent

time series, making it particularly useful for analyzing long-term trends in climate, hydrology, and
land use. Additionally, remote sensing data is often available at high spatial resolutions, which is
essential for detailed environmental monitoring and precise applications, such as water allocation
and disaster forecasting. Unlike in-situ data, RS datasets are also typically free or low-cost and are
not restricted by national boundaries, which allows for cohesive analysis at a basin, continental
or global scale.

RS enables the collection and estimation of essential data for effective transboundary water
resource management. The main data derived from RS relevant for water applications includes
precipitation, evapotranspiration, soil moisture, vegetation and land cover, groundwater, surface
water, snow and ice, and water quality. In the context of Africa, data from all these variables,
except for snow and ice, are crucial for managing water resources. In addition to supporting
applications such as flood and drought hazard mapping, RS data can assist tracking changes in
land use and land cover, analyzing vegetation indices, and assessing agricultural water
productivity5. Furthermore, RS plays a vital role in basin-scale water accounting, offering
consistent and reliable data for evaluating water availability, usage, and sustainability, while also
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contributing to broader climate and environmental assessments .

Furthermore, RS data brings strategic value in the political context by enabling open data-
sharing practices and fostering trust and collaboration among countries. RS data allows riparian
countries to address transboundary water problems, such as drought and flood forecasting on
transnational rivers, and facilitates broader discussion on sharing of water resources. Recent
advances in cloud storage and computing power have also made RS data more accessible,
allowing it to be stored and analyzed in real-time on a global scale, often at low cost. Publicly
available RS data and data products enhances transparency and equity in transboundary water

governance by providing unrestricted access to consistent hydrological information across
national borders. This accessibility improves collaboration among riparian countries, reduces data
ownership disputes, and supports evidence-based decision-making for sustainable
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management .

6 García, L.E., Rodríguez, D.J., Wijnen, M., & Pakulski, I. (Eds.). (2016). Earth observation for water resources management: Current use and
future opportunities for the water sector. Washington, DC: World Bank Group.
7 Bastiaanssen, W.G.M., Molden, D.J., & Makin, I.W. (2000). Remote sensing for irrigated agriculture: Examples from research and possible
applications. Agricultural Water Management, 46(2), 137–155.
8 Christina Leb, “Data Innovations for Transboundary Freshwater Resources Management: Are Obligations Related to Information
Exchange Still Needed?” in Data Innovations for Transboundary Freshwater Resources Management (2020): 3–78,
https://doi.org/10.1163/9789004429000_002.
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