Integrating groundwater stress in life-cycle assessments – An evaluation of water abstraction

Abstract

Understanding groundwater abstraction effects is vital for holistic impact assessments in areas depending on groundwater resources. The objective of our study was to modify the state-of-the-art AWaRe (available water remaining), freshwater impact assessment specifically for use in LCAs in areas dependent on groundwater resources. The new method, called "AGWaRe" (available groundwater remaining), reflects groundwater availability, based on a fraction of available groundwater remaining locally relative to a reference. Furthermore, our method increases spatial resolution beyond 1770 km grid cells and adjusts demarcations in order to improve the representation of the heterogeneity of groundwater catchments. The applicability of AGWaRe was demonstrated on three groundwater systems producing 5 million m water for the city of Copenhagen, namely Advanced Treatment of Groundwater, Simple Treatment of Groundwater and Infiltration of Reclaimed water. Results were normalised to compare with other effects of supplying water to an average Danish person. The normalised impacts for drinking water for one person ranged between 0.1 and 39 PE (person equivalent) for the three systems, which indicates that effects on groundwater resources differ substantially between systems. A comparative LCA of these groundwater systems shows that other impact categories range between 0 and 1 PE/person. Advanced Treatment of Groundwater generally has the lowest effect, for example <50% of the other groundwater systems in Global Warming Potential. The AGWaRe results indicate that freshwater impacts from Simple Treatment of Groundwater are up to 100 times greater than for Infiltration of Reclaimed water. Furthermore, AGWaRe exposes differences between the groundwater systems that AWaRe cannot evaluate, because one AWaRe cell covers two of the systems in question. These improvements are crucial for groundwater managers looking to include sustainability considerations in their analysis and decision-making.

An eco-efficiency evaluation of community-scale rainwater and stormwater harvesting in Aarhus, Denmark

“…The impacts were calculated according to the International Reference Life Cycle Data System (ILCD) (EC-JRC, 2010) for the following categories: reserve base resource depletion (RD-reserve), fossil resource depletion (RD-fossil), climate change (CC), ecotoxicity (E-TOX) and particulate matter (PM). Freshwater depletion (FD) was calculated as suggested for GW-based water supplies (Gejl et al, 2018). Calculations are provided in Appendix B in the Supplementary Material.…”

Relating wellfield drawdown and water quality to aquifer sustainability – A method for assessing safe groundwater abstraction

“…global and regional, aquifers (Gleeson et al, 2012) with an average area of 50 000 km 2 and therefore give little consideration to local water abstraction challenges in smaller groundwater catchments (Hybel et al, 2015). The indicators mentioned above generally focus on surface water, which can result in misrepresentations of the groundwater impact (Gejl et al, 2018). Throughout Europe, 50% of drinking water supplies relies on groundwater (Völker and Borchardt, 2019), and it is a significant resource for industrial and agricultural water demands (Jones and Anthony, 2011).…”

Understanding the impacts of groundwater abstraction through long-term trends in water quality

“…Groundwater is an important resource around the world (Gleeson et al, 2012;Margat and van der Gun, 2013), and some countries are entirely dependent on it for their water supply, for example Denmark. In spite of an increasing focus on the assessment of groundwater resources (Gejl et al, 2018;Gleeson et al, 2012), there is still potential for better representation of aquifer deterioration in terms of both groundwater levels and water quality. Such a quantification could ensure the efficient use of this vital resource and the management of future water availability (Li and Qian, 2018).…”

“…Moreover, they are useful for screening purposes, given that they are based on precautionary principles; however, they are at the midpoint level for identifying environmental mechanisms (Bare et al, 2000) and do not deal with actual impacts or deterioration of the water resource itself. Some evaluations consider surface and groundwater as one resource, resulting in misleading effects for the latter's withdrawal (Gejl et al, 2018). Furthermore, the above-mentioned indicators are scoped mainly towards global or regional issues and they give little assistance to local challenges.…”

“…Furthermore, the above-mentioned indicators are scoped mainly towards global or regional issues and they give little assistance to local challenges. We previously proposed a generic indicator aimed specifically at the local impacts of groundwater abstraction, which was applied to groundwater supply systems in Denmark (Gejl et al, 2018), but this indicator is also limited by the use of generic and globally utilized definitions of the water balance. In the following, we investigate the long-term effects of water abstraction on aquifer deterioration, by studying the relationships between abstraction, groundwater level and groundwater quality based on groundwater monitoring data for 28 well fields providing water to Copenhagen, Denmark, which have been influenced by abstraction for decades.…”