21.1 Introduction
21.2 Valuing the Benefits of Groundwater Protection with Contingent Valuation: A Review
21.2.1 Methodological Approaches for Valuing Groundwater Protection Benefits
21.2.2 The Integrative Capacity of Contingent Valuation Method
Reference | Yeara | Country | Location | Objective/issue | Average WTP (current currency value)b | Average WTP (PPP€2013)c |
---|---|---|---|---|---|---|
Edwards (1988) | 1986 | United States | Cape God, Community of Falmouth, Massachusetts | Benefits of reducing the probability of groundwater contamination | 286–1130 $1986/hh/year | 523–2065 €/hh/year |
Wright (1988) | 1987a | United States | Peninsula Township groundwater resources, Michigan | Benefits of protecting groundwater (nitrates) | 296–696 $1987/hh/year | 523–1230 €/hh/year |
Shultz and Lindsay (1990) | 1988 | United States | Dover Community, New Hampshire | Benefits of reducing the probability of groundwater contamination, individual community | 129 $1988/hh/year | 220 €/hh/year |
Sun et al. (1992) | 1989 | United States | Dougherty County, Georgia | Benefits to citizens of protecting groundwater supplies from agricultural chemical contamination | 641 $1989/hh/year | 1050 €/hh/year |
Powell et al. (1994) | 1989 | United States | 15 communities in Massachusetts, New York and Pennsylvania | Benefits of groundwater quality protection (agricultural chemicals, landfills, accidental spills and toxic chemicals) | 62 $1989/hh/year | 102 €/hh/year |
Caudill (1992) | 1990 | United States | Michigan state | Benefits of protecting groundwater (nitrate and pesticides contamination) | 34–69 $1990/hh/year | 53–108 €/hh/year |
Wattage (1993) | 1991 | United States | Bear Creek Watershed, Story and Hamilton counties, Iowa | Benefits of groundwater quality improvement (nitrates, pesticides) | 90 $1991/hh/year | 135 €/hh/year |
Lazo et al. (1992) | 1991a | United States | Denver, Colorado | Non-use benefits expected from groundwater quality improvement (domestic waste) | 34–42 $1991/hh/year (2,81–3,54 $1991/household/month) | 51–64 €/hh/year |
McClelland et al. (1992) | 1991 | United States | National assessment | National benefits of cleaning groundwater contaminated by landfills, contaminates not specified | 168 $1991/hh/year (14 $1991/household/month) | 253 €/hh/year |
Jordan and Elnagheeb (1993) | 1991 | United States | Entire state of Georgia, US | Benefits of improving drinking water quality | 121–149 $1991/hh/year | 182–224 €/hh/year |
Poe and Bishop (1993) | 1991–1992 | United States | Portage County, Wisconsin | Benefits of protecting groundwater such that nitrate contamination levels would be below USEPA health advisory standards for the entire state of Georgia | 225–685 $1991/hh/year | 339–1031 €/hh/year |
Stenger and Willinger (1998) | 1993 | France | 10 communities located on the Alsatian aquifer | Benefits of preserving groundwater quality (various types of contaminants) – water users | 617 FF1993/hh/year | 129 €/hh/year |
Bergstrom and Dorfman (1994) | 1993a | United States | Groundwater resource Dougherty County | Benefits of preserving groundwater quality (for domestic water supply) | 320–2360 $1993/hh/year | 455–3353 €/hh/year |
de Zoysa (1995) | 1994 | United States | Maumee and Erie Lake Basin, Ohio | Benefits of groundwater quality improvement | 53 $1994/hh/year | 73 €/hh/year |
Rozan et al. (1997) | 1995 | France | Two communities close to the Alsatian aquifer | Benefits of preserving groundwater quality (various types of contaminants) – non users | 340 FF1995/hh/year | 69 €/hh/year |
Lichtenberg and Zimmerman (1999) | 1995 | United States | Maryland, New York and Pennsylvania states, Mid-Atlantic region | Farmers’ WTP for groundwater protection (pesticide leaching prevention) | 1112–7078 $1995/farmer/year (17–35 $1995/acre/year) | 1495–9517 €/agriculteur/an |
Martin and Marceau (2001) | 1997 | Canada | Five districts North of Montréal | Benefits of groundwater status improvement (quality, quantity) | 48 $CAN1997/hh/year | 49 €/hh/year |
Belloumi and Matoussi (2002) | 1997 | Tunisia | Oued Kheirate groundwater | Benefits of preserving groundwater quality (saline intrusion) | 20 dinars2002/hh/year | 41 €/hh/year |
Grappey (1999) | 1997–1998 | France | Bièvre-Liers plain aquifer, Isère | Benefits of preserving groundwater quality (nitrates) | 251–402 FF1997/hh/year | 49–79 €/hh/year |
White et al. (2001) | 1999 | New Zealand | Waimea plain (seven aquifers) | Benefits of improving the quantitative status of groundwater | 183 $1999/hh/year | 152 €/hh/year |
Wei et al. (2007) | 2004 |
China
| Fengqiu County, Henan Province, North China Plain | Benefits of protection and restoration of groundwater (overexploitation) | 1.26 Yuan2004/hh/year | 0.39 €/hh/year |
Hasler et al. (2005) | 2004 | Denmark | National assessment | National benefits associated with increased protection of the groundwater resource (nitrates, pesticides) | 711 DKK2004/hh/year | 87 €/hh/year |
Rinaudo and Aulong (2014) | 2006 | France | Upper Rhine valley quaternary aquifer, France | Benefits of protecting and improving groundwater quality (chlorinated solvents) | 42–76 €2006/hh/year | 47–85 €/hh/year |
Brouwer et al. (2006) | 2006 | The Netherlands | Scheldt basin | Benefits of protecting and improving groundwater quality | 31–72 €2006/hh/year | 36–84 €/hh/year |
Miraldo Ordens et al. (2006) | 2006 | Portugal | Aveiro Quaternary aquifer | Benefits of protecting groundwater quality | 38 €2006/hh/year | 54 €/hh/year |
Pakalniete et al. (2006) | 2006 | Latvia | Shallow part of the groundwater body under Riga | Benefits of groundwater quality improvement | 25 €2006/hh/year | 71 €/hh/year |
Strosser and Bouscasse (2006) | 2006 | Slovenia | Krska kotlina aquifer | Benefits of protecting groundwater quality | 1346–2493 SlT2006/hh/year | 120–222 €/hh/year |
Chegrani (2009) | 2006 | France | Artois chalk and Lys valley aquifer | Benefits of improving groundwater quality (nitrates and pesticides) | 24 €2006/hh/year | 27 €/hh/year |
El Chami et al. (2008) | 2007d | Lebanon | Byblos district | Benefits of the improvement of groundwater quality for irrigation (seawater intrusion) | 102–167 $2007/irrigating farmer/year | 104–170 €/hh/year |
Rinaudo (2008) | 2008 | France | Lower Triassic Sandstone aquifer | Benefits of stopping the over exploitation of the aquifer | 40€2008/hh/year | 43 €/hh/year |
Tentes and Damigos (2012) | 2009 | Greece | Four towns located on the Asopos river basin aquifer | Industrial pollution, especially by Cr(VI) Benefits for restoring groundwater quality | 180–239 €2009/hh/year (15–20 €2009/household/month) | 227–301 €/hh/year |
Hérivaux (2011) | 2010 | Belgium | Meuse alluvial aquifer near Liège | Benefits of restoring groundwater quality | 40 €2010/hh/year | 42 €/hh/year |
Martinez-Paz and Perni (2011) | 2010 | Spain | Gavilan aquifer, Segura basin | Benefits of improving water quality and quantity of the associated wetland | 24 €2010/hh/year | 29 €/hh/year |
21.2.3 The Limits of CV for Groundwater Economic Valuation
21.3 Empirical Case Studies: Objectives and Methodology
21.3.1 Context and Motivation for Conducting Two Additional Case Studies
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Is contingent valuation an appropriate method for monetary valuation of benefits associated with groundwater protection and restoration, in locations where (1) people do not directly use groundwater through wells, and (2) where they have a very limited knowledge of groundwater resources?
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If appropriate, what type of information should be provided to respondents to make sure that they properly understand the multidimensional nature of the benefits associated with groundwater protection and restoration?
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Finally, what are people’s stated preferences for the different components of groundwater protection and restoration benefits? Do they integrate use and non-use benefits, short and long term benefits?
21.3.2 Case Studies
Characteristics | Meuse alluvial aquifer (MAA) Liège region, Belgium | Lower Triassic Sandstone (LTS) Lorraine region, France |
---|---|---|
Aquifer type and scale | Shallow alluvial aquifer (15 m depth) Local resource | Deep confined aquifer (0–800 m depth) Regional resource |
Type of territory | Densely populated urban area | Rural area |
Management problem | Industrial pollution (brownfield) |
Overexploitation
|
Groundwater
use
| Industrial Drinking water wells abandoned due to pollution Very few private wells | Main resource for municipal supply, food and beverage industry, industrial water bottling and cattle farms |
Expected benefits | Ecological improvement of dependent ecosystems (indirect benefit) Improvement of natural heritage (bequest value) and potential future use (option value) | Continued long term access to groundwater implying continuation of cheap municipal supply in the future; and reduced risk in case of drought or contamination of superficial water resources |
21.3.3 Overview of the Common Methodology Deployed in the Case Studies
21.3.4 Sending Clear Messages About the Benefits of Groundwater Protection
21.4 Empirical Results
21.4.1 The Impact of Prior Knowledge and Information Supply on WTP
21.4.2 Motivations Underlying WTP
Meuse Alluvial Aquifer | Lower Triassic Sandstone aquifer | |||
---|---|---|---|---|
Willingness to pay
% accepting to pay Average WTP/year/household | 66 % 40 € |
Willingness to pay
% accepting to pay Average WTP/year/household | 67 % 39 € | |
Main motivation for paying
|
Main motivation for paying
| |||
Bequest
value
| To pass on to future generation groundwater of better quality | 49 % | Groundwater is what my grandchildren will drink in 40 years | 52 % |
Indirect use
value
| To improve the quality of dependent ecosystems (fauna, flora) in the Meuse valley | 22 % | ||
Option
value
| To make possible future use of the aquifer for the city of Liège if needed | 22 % | I prefer to pay now for groundwater protection than later to bring water from far away | 19 % |
Direct use
value
| To keep the possibility of using groundwater through a private well | 3 % | I accept to pay because I use this aquifer/my drinking water supply depends on it Depleting this aquifer would represent a handicap for the local economy | 20 % 9 % |
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In the first group, the concern for future generations is the main motivation for paying (respectively 49 % and 52 % of the MAA and LTS samples). Groundwater is clearly perceived as a natural heritage which should be preserved to guarantee future generations wellbeing, either as a clean, cheap and protected drinking water source or as a support of the local economy. For these respondents, higher WTP may reflect a feeling of moral responsibility for contributing to the protection of groundwater for future generations. WTP reflects altruism more than economic self-interest. In the LTS, the econometric analysis shows that respondents ranking by future generation as a first motivation have an 11 % higher WTP (variable “futgen” significant at the 1 % level, see Appendix).
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The second group comprises respondents whose main motivation is protecting (LTS) or restoring (MAA) the groundwater resource which they could personally be using in the future. WTP stated by these respondents thus reflects the option value of groundwater, defined as the benefits that could be derived from potential future use. Their WTP is not statistically different from the average.
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The third group is mainly motivated by the protection of a resource which they already use, either directly through a private well, or indirectly when their municipal water supply depends on groundwater. They represent approximately 20 % of respondents in the LTS, but only 3 % in the MAA where the aquifer is not usable in its current status. In LTS, these respondents have a statistically lower WTP than the sample average.
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The fourth groups say their main motivation is to contribute to the environmental improvement of dependent ecosystems. They represent 22 % of the MAA sample. This motivation is not expressed in the LTS due to the confined nature of the aquifer, and the absence of an impact on surface dependent ecosystems.
21.4.3 Mental Models and Embedding Effects
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Due to insufficient knowledge, some respondents perceive groundwater as a ubiquitous and uniformly distributed resource, rather than a collection of well-defined and spatially delineated reservoirs. These respondents are thus not able to make a clear distinction between protecting groundwater in a broad sense on the one hand, and protecting a specific aquifer on the other hand. This remains true even if maps and schemes are provided in the survey. The existence of such an embedding effect is supported by much evidence in our two case studies: in the MAA, we asked respondents who accepted to contribute if they would be willing to contribute for any other groundwater body. The answer was positive for 71 %, with 41 % declaring the same WTP. In the LTS, 44 % of the respondents declared they would consent to pay a similar amount for the protection of any other aquifer in France. Such results cast doubts on the meaning of elicited WTP values, which could be considered as the WTP to protect groundwater resources in general (and not specifically the groundwater body under study).
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The second embedding effect is more specifically linked to situations where groundwater protection or restoration programs generate a wide range of environmental benefits. This effect is observed mainly in the MAA case study where some respondents faced difficulties in clearly disentangling those benefits derived from groundwater quality improvement from those of other environmental benefits. Especially in the context of orphan brownfields management, it is clear that actions aiming at improving groundwater quality will also bring other types of benefits to the population (positive landscape amenities, improvement of soil quality, etc.). Even if a survey clearly focuses on groundwater resources we cannot be sure that all respondents accept the implicit mental model used by the researcher in designing the survey. Results provide evidence of this risk: respondents who declare being concerned by a high number of environmental problems have a higher probability of accepting to pay, and a greater WTP. This reflects a difficulty for respondents to disconnect groundwater resources from other environmental compartments (air, soil, surface water, etc.). The survey may have influenced them in that direction by explaining the link between contaminated soil and groundwater quality on the one hand, and groundwater quality and surface ecosystems on the other hand. Such a result raises doubts as to the meaning of the WTP value, which could be considered as their WTP to improve the environment quality in general in their community (and not specifically the groundwater resource).