The cumulative effect of unconventional exploitation on water stress and demand on local water resources

Bertram, Douglas and Shipton, Zoe (2017) The cumulative effect of unconventional exploitation on water stress and demand on local water resources. In: Transatlantic Knowledge Sharing Conference on Unconventional Hydrocarbons, 2017-06-21 - 2017-06-22, De Bazel Conference Centre Vijzelstraat.

Full text not available in this repository.Request a copy from the Strathclyde author

Abstract

One of the most discussed aspects of unconventional gas extraction (UGE) is the effect on water resources, yet recent research focuses on water contamination (water quality) and has not considered water stress (water quantity). UGE is a water intensive industry; water consumption of 3 million gallons per shale gas well have been reported as typical in the USA. Such water needs may challenge supplies and infrastructure: a similar UGE water demand for the UK shale resource could be as much as three times the annual Scottish whisky industry water requirement (~16 billion gal total water; both cooling water and whisky product). Thus a nation-wide programme of UGE is likely to place extra demands on existing water resources. CERES’ USA-wide study notes “nearly half of the wells hydraulically fractured since 2011 were in regions with high or extremely high water stress, and over 55 per cent were in areas experiencing drought.” UK shale resource areas all lie within, or close to, regions that are either prone to drought now, or are drought forecast in 50-70 year projections. If a similar US water demand model were employed in the UK, the growth of UGE could place additional stress on existing water resources. A significant challenge is securing a sustainable water supply while protecting existing water resources. Use of potable water places stress on domestic supplies and water use by other industries already in place. This is particularly relevant to cumulative effects of an up-scaled, nation-wide industry. The trade-offs and interdependencies between treatment requirements, environmental impacts, and social/economic impacts of different water supplies must be considered to get the most benefit from UGE. This paper uses the Scottish shale gas resource as a case study to assesses the potential for water stress associated with UGE and examines the longer-term environmental sustainability of cumulative UGE water demands with existing and future water resources. Combining recent water resource planning with UK climate change projection scenarios (UKCP09) and rainfall data for Scotland, an appraisal using GIS-based mapping and analysis, is made of likely water demands and available resources for specific zones in Scotland and assessed to determine potential water stress. Initial studies show that while UGE is unlikely to have a significant impact on the long-term availability of water in Scotland. If 10% of the total wells required were to be fractured within one three month summer period around 2080, then the water demands of UGE would account for 4% of the total potable water available. The study highlights the need for appropriate measures ensuring that to protect regional water resources and ensure future water supply availability a UGE schedule must be managed and exploited. The lessons learned from this study can be further developed for the rest of the UK and European contexts.