Background
Lack of information for decision-making
Water problems around the world are increasing; however, information useful for decision-makers within the water sector and related to the water sector seems to be decreasing. Solving water problems requires information from many disciplines, and the physical accounts (describing sources and uses of water) are the most important foundation. The information has to be coherent and harmonized in order to provide an integrated picture useful for the assessment of the problems. The current hydrological data democracy does not provide all the required data necessary for proper water consumer communication, which hampers the development of good water stewardship.
Why water accounting?
There is a need to describe water resources in a standard context, using clear terminology and a standard data collection system with known quality standards. Vaporization of water from land into the atmosphere – as well as water in products – produces agro-ecological–economical services. These services should be understood and improved if we want to maintain current per capita water availabilities and water footprints. Water consumption and water pollution need to be regulated. Audited Water Accounts are the basis for evidence-based decision-making and establishing agreements with riparian partners, including those across international borders.
Data integration
Water accounting integrates hydrological processes with land use, managed water flows, and the services that result from water consumption in river basins. Its objective is to strive to achieve equitable and transparent water governance for all users and a sustainable water balance Users can provide value assessments of certain process, and more accurate data sets, that replaces the default data collected from open access sources that represent best estimates. Water accounting was developed originally by Dr. David Molden from the International Water Management Institute (IWMI). The Water Accounting Plus methodology (WA+) is applied to river basins, and utilizes open access (remote sensing) datasets. It is a multi-institutional effort from international knowledge centers (IWMI, IHE Delft, FAO, and WWAP) that are neither politically or geographically connected to a given river basin. WA+ provides independent estimates of water fluxes and stocks of water resources availability, consumption and derived services, that can be generated near real time.
