The System of Environmental-Economic Accounting (SEEA) presents a method for compiling and analyzing environmental data for economic analysis and evaluation. The SEEA-Water provides such an approach especially for compiling water accounts and for assessing the economic value of water resources. A concise methodology has been developped and adopted as an interim international statistical standard by the United Nations Statistical Commission (UNSC).

“SEEA-Water is fully coherent with the broader SEEA. It elaborates and expands the guidance on accounting in the International Recommendations for Water Statistics (IRWS). UNSD coordinated the preparation of SEEA-Water in collaboration with the London Group on Environmental Accounting.” (UNSTATS)

The report with a detailed methodology, definitions and tables for compiling SEEA-Water Accounts is published on the UNSTATS web-page.

There are several case studies for SEEA-Water Accounts. A regional case study is presented for the Namibian part of the Okavango River Basin that has then been integrated into a study on water accounts for the entire Cubango Okavango River System. A previous attempt to develop water accounts for Namibia in a pilot study has been presented.

Australia prepares National water accounts and has prepared a good documentation of how these accounts are being compiled. Water accounts are prepared per annum. SADC has prepared a description of methodology for the SADC region .

The SADC region has prepared a quite comprehensive documentation for establishing water accounts. It includes also training material, lessons learnt and background information.

The water footpring approach is not that different. An introduction to this concept and a global appreciation of results is provided by Hoekstra et al. (2011). Appendices contain details on the methodology. See also Mekonnen & Hoekstra (2011).

The Netherlands have worked on national water accounts and provide an interesting perspective on water accounts and on the water framework directive. The work was done by the water footpring group.

Finally, Spain provides a basin-based approach to water accounts for a transnational basin.

An even broader approach is presented by the Wavespartnership including ecosystem services.

Putting together water accounts requires an in-depth hydrological and hydrogeological knowledge. Water Accounts are well defined in terms of definitions, scope and purpose. The practical task of putting these accounts together, however, requires knowledge about meteorology, hydrology, hydrogeology and the respective data sources, data processing and institutions of each specific country.

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Teaching SEEAW requires an introduction to the economic, environmental and hydrological concepts and techniques. The practical application further requires knowledge of the institutional arrangements and data policies. Furthermore, SEEAW requires some aggregation, disaggregation, re-formating and transformation of data. Some of the variables need to be derived based on estimation equations.

For the estimation of groundwater stocks it is relevant to know the depth to groundwater, porosity and the change of porosity with depth (usually there is an exponential decline with a specific decay constant k down to a depth, where groundwater is typically not found anymore because of the high pressure exerted by the overburden).

The total amount of groundwater available at a certain point in time can be derived from GRACE data (Link to Grace data).