Lunch talk by Guoping Zhang (Water Footprint Network)

Title: “Water Footprint Assessment for the South East Region North East Thames Area, Environment Agency, UK”

Abstract for the presentation:

The pressure on the water resources of the greater London (London Rivers) area is mounting as the environment (e.g. climate and land-use) and society (e.g. population and lifestyle) are changing. The way water abstraction is currently managed is not responsive or flexible enough to address these future pressures. The cost of abstraction licenses does not reflect the relative scarcity or abundance of water, and charges do not vary to reflect competing demands for water. As a response to these issues, the Government has therefore committed to reforming the abstraction management regime to improve the sustainability of water use and management. A Water Footprint Assessment (WFA) study for the South East Region North East Thames Area (SENET) was carried out to assist the Environmental Agency in better understanding the interconnection between water availability, water supply and water use and provide insight in the efficiency and sustainability of water use.

This is a pioneering project in the field of WFA on the catchment scale in a regulatory context. The study deals with a high level of complexity in terms of a number of aspects: 1) high spatial and temporal resolution (namely sub-catchment level and monthly time scale); 2) multiple water use sectors (industry, domestic and agriculture); 3) different sources of water (surface and groundwater) for human use; 4) different types of human pressure on water resources (consumption and pollution), and 5) integrated assessment of water use sustainability (water scarcity and water pollution level).

This study assessed the WF of 35 sub-catchments of Colne, Lee, Brent and Crane and Roding-Beam-Ingrebourne (RBI) catchments in the North-eastern part of the Thames River basin. The blue, green and grey water footprints on surface water and groundwater have been estimated for the domestic, industrial and agricultural sectors on a monthly basis for the baseline condition (average over 2002 – 2007). The sustainability of blue and grey WFs for these sub-catchments under the baseline condition was assessed using the blue water scarcity (BWS) and water pollution level (WPL) indicators. The blue, green and grey water footprints, and the BWS of each sub-catchment were projected to 2060 based on the climate change and water demand change scenarios. Recommendations for water footprint response strategies were put forward based on the baseline and projected WFA results.