The Nile river basin is enormous.
Shared by 11 countries and with a drainage area that covers over 3 million square kilometers, management of the basin has necessarily spawned national and regional bodies (like the Nile Basin Initiative [NBI]). It would be great to know how much water is flowing into and out of such a large area, and to have information on how it was being used, processed, and captured in order to better manage it. But access to the data collected by national hydrological monitoring networks is limited. Historically, it has been difficult to comprehensively measure basin-wide flows.
That is where the Water Accounting+ (WA+) framework enters the equation.
In December, I joined a roundtable meeting in Addis Ababa, Ethiopia where regional water professionals from East Africa were asked to provide feedback on the WA+ sheets for the Nile. These sheets were made using public domain remote sensing data and global hydrological models, bringing all of it together in an easy to understand and visually pleasing way.
What is WA+?
Very well explained in the Thrive post Information wants to be free, WA+ is trying to account for all of the water in a system, such as a river basin. The framework takes this information, puts them into tables, and translates them into thematic sheets, which present the raw data in a topically coherent way. The data tables and thematic sheets are then made available and regularly updated on the platform website.
What is unique about WA+ is that it primarily uses publicly accessible remote sensing data. In the past, water accounts were balanced based on what information was available on the ground. However, this data is often spotty and inconsistent, especially in the developing world. In addition, nation states and government ministries have sometimes been cagy about releasing their data, especially if actions in one country or sector have the potential to negatively affect the water resources in, or availability for, another.
So what came out of the meeting in Addis?
Some of the members of the roundtable were concerned that the numbers that the WA+ team were getting from remote sensing sources diverged from the numbers that were being coming from ground studies or that were commonly used by national governments. The team recognized the critical need for validation by independent experts, and where available, on the ground data. However, it was also widely recognized by participants in the room that national level datasets are often not up-to-date, especially in comparison to remote sensing data that are both independent and timely.
“Our hope is that the information we get from satellites, by making the data more public, can then be paired with local knowledge and data to create a more complete and accurate picture,” said Wim Bastiaanssen, who is a member of the project from UNESCO-IHE.
“By having more complete information and providing up-to-date, transparent and politically independent data, we hope to help governments and river basin authorities to make better and more informed decisions. This is the ultimate objective of the open access WA+ platform,” concluded Lisa-Maria Rebelo, IWMI researcher and remote sensing specialist.
What are some practical uses of WA+ for better basin management?
WA+ provides a method to regularly report on the water resources situation within a basin and its subbasins. This information is critical to understand which flows can be manipulated by means of retention, withdrawals and land-use change, and where are the options to increase the efficiency of water use for different purposes.
As the approach is based on land use classes, WA+ has the potential to show how changes in land use over time impact the flow of water across a basin. This kind of information can lead to better long-term planning for governments and investors.
In irrigated crop systems, the WA+ sheets for the Nile showed some non-consumed water flowing out as run-off from fields, which is functionally a waste of water. In addition, some of the water in the basin that was categorized as ‘non-beneficial’ is because of evaporation from wet soils due to over irrigation. WA+ can be used to identify where efforts to make irrigation more efficient would be best placed.
Finally, there are plans to expand the WA+ sheets to look at hydrological ecosystem services, which would help to place value on these services and lead to increased agricultural productivity and ensure a sustainable water balance.
Effectively, the project is looking first at basins like the Nile where there is already some data in order to test the methodology and to set up a verification and review protocol. WA+ can then be expanded into other basins where there isn’t as much data in order to help fill these more pronounced information gaps and contribute to better informed and holistic policy planning and implementation.
The feedback given at the roundtable highlighted one of the big challenges that the project still faces: how to get buy-in from national governments when the sheets are at the basin scale. Suggestions from participants included involving ministries in ground truthing the numbers so they feel invested in the project, or looking for ways the tool can provide solutions to some key national issues. Another recommendation was to use WA+ to help nation-states improve their water use efficiencies according to what they already committed to for the UN Sustainable Development Goals (SDGs).
“You should show that water can be a linking force,” one of the participants said. “There is a lot of suffering when there is too much or too little water, so WA+ is useful if it can show the connectivity in the basin and provide relief for those who suffer.”