Establishing what groundwater is and who owns it is just part of the task of groundwater law. Its main function is to manage groundwater quantity by setting limits on total extraction to achieve a variety of objectives, and by controlling extraction as between individual users, in many cases by assigning individual rights to extract. The first step towards doing that is to decide what level of government to entrust with those regulatory tasks. The experiences of Australia and the EU show varying degrees of supra-state (federal and EU, respectively) involvement and coordination in certain high-level aspects of groundwater policy and law, but allocating water to individual users remains uniformly the task of lower levels of government. In the western US, the federal government has almost no formal role.
3.1 Who Regulates Groundwater Quantity?
Different jurisdictions allocate responsibility for regulating groundwater differently as between local, state and federal governments. Broadly, the locus of responsibility for groundwater quantity regulation reflects the general degree of acceptance of centralised government in each region, with responsibility tending to lie higher in government hierarchies in the EU and Australia and lower in the western US.
Western US states are generally responsible for regulating groundwater quantity, though in some states (as in Nebraska and most regions of California), this role is assumed by local governments. The federal government is directly involved in groundwater quantity concerns to a much lesser degree, for example, through funding mechanisms (Leshy 2008b).
Until very recently, Australia approached groundwater quantity regulation in much the same way: states had carriage of water allocation
issues, and federal influence was felt mainly through funding mechanisms. However, after over a decade of federal water policy driven by economic incentives offered to the states, the federal
Water Act 2007
introduced a much more direct federal role. This is particularly so in the Murray-Darling Basin
, an agriculturally and ecologically critical basin the size of France and Spain combined. Under arrangements that are yet to come fully into effect, the federal government sets Basin-wide limits on surface water and groundwater extraction, while states continue to allocate water to individual users within those overall caps.
In contrast to western US states (among which there is no coordination on groundwater quantity administration) and Australian states (among which there is coordination in policy, through the National Water Initiative, but relevant overarching law only in the Murray-Darling Basin
), the EU’s Water Framework Directive more strongly coordinates the regulation of groundwater quantity among Member States by establishing goals and planning processes in supra-national law. Actual water allocation
is carried out by different authorities and agencies at different levels.
The issue of regulatory responsibility aside, the key substantive function of groundwater law is to manage groundwater extraction to achieve particular objectives. This can occur at both a macro- (i.e. basin-) scale, or at the level of individual rights to extract the resource. Though not discussed here, another focus of groundwater quantity law is requiring well spacing to control interactions between wells, and regulating well construction methods to prevent pollution.
3.2 Macro-Level Controls: Establishing Groundwater Withdrawal Limits Through Plans and Other Means
Jurisdictions use a variety of principles for establishing overall (e.g. basin-wide) withdrawal limits that restrict the allocation of groundwater rights—concepts like “safe yield
” (western US), “good groundwater status” (EU), and “environmentally sustainable diversion limits” (Australia). In some cases, these overall withdrawal limits are established by management plans—an approach strongly favoured in Australia and the EU.
In most western US states, there is a weaker focus on overall basin extraction limits than in Australia or the EU, perhaps because of the absence of a water planning tradition (Chapman et al. 2005), and reliance on a common law tradition of water allocation. A disadvantage of the western US common law approach in contrast to Australia’s water allocation planning approach is the relative difficulty of changing vital concepts like the principles that limit extraction, and how those principles are exercised in a particular year, to match changing water availability and also the modern recognition of the environmental water needs of groundwater-dependent ecosystems (Pilz 2010).
Walnut Creek Intensive Groundwater Use Control Area, Kansas
In the middle of Kansas, Cheyenne Bottoms lies on one of the busiest, globally significant shorebird migration paths. During their spring migration, about 45 % of North America’s shorebird population, up to 600,000 individuals, use these wetlands, which are the largest in the interior US. By 1989, groundwater pumping to support the agricultural economy surrounding the wetlands had depleted Walnut Creek, the source of a surface water right held by the Kansas Department of Wildlife and Parks to water the wetlands. They were completely dry during the height of spring migration (Hays 1990). In response to these effects, the Kansas water rights administrator, the State Engineer, took the unprecedented step of declaring an “intensive groundwater use control area” and establishing rules to ban new groundwater pumping, cut back on existing groundwater rights, and introduce a “cap and trade” system for irrigation water rights. At the time, farmers predicted that groundwater pumping restrictions would have devastating economic effects. However, a 2011 economic analysis suggests that the initially significant economic effects of these rules diminished rapidly, so that in the long-run, producers made the same amount of money from crops while using less water (Golden and Leatherman 2011).
Where they exist, water plans in the western US tend to be used as water supply planning tools “designed to insure that adequate water is available for certain kinds of uses” (Wadley and Davenport 2013) rather than tools for setting basin-scale limits on water allocation.
California provides an example of this approach: the California Water Code provides for various kinds of water management plans, including groundwater management plans, but these generally do not affect groundwater allocation (Nelson 2011b). Some western US states that have made recent changes to their groundwater management regimes have introduced the concept of water plans that are capable of constraining groundwater allocation to within cumulative caps (as in groundwater planning processes that aim to achieve “desired future conditions” in Texas (Witherspoon 2010)). Some other western states have water plans that affect groundwater allocation in a few designated groundwater areas that are recognised to require special management (e.g. Intensive Groundwater Use Control Areas in Kansas (Sophocleous 2012; and see text box)). In some eyes, a water planning approach is highly controversial, interpreted as an attack on a “pure” prior appropriation system, where seniority and “beneficial use” are the major determinants in allocating water (Wilkinson 1991).
Rather than using a planning mechanism, western US states tend to express overall extraction limits through state statutes and sometimes through judicial precedent, though on occasion neither is particularly clear. Some western US state statutes explicitly limit extraction to “safe yield
”—roughly, constraining groundwater extraction to the level of natural and artificial recharge (e.g. Arizona Revised Statutes section 45-561(12), 45–562)—or some variation of that concept. However, as a technical concept, safe yield has been discredited as a management tool capable only of protecting against groundwater over-exploitation, since it ignores discharge points at surface water bodies and ecological users of groundwater (Alley et al. 1999). Some states increase or decrease the allowable extraction above or below the level of recharge by qualifying the concept of safe yield to include other aspects, for example, those related to economics and water quality impacts. In Washington, safe yield prohibits the state from granting appropriative rights beyond the basin’s capacity to yield water within a reasonable or feasible pumping lift in case of pumping developments, or within a reasonable or feasible reduction of pressure in the case of artesian developments (Revised Code of Washington § 90.44.070). In Utah, safe yield means extracting the amount of groundwater that can be withdrawn from a basin over a period of time without exceeding the long-term recharge of the basin or unreasonably affecting the basin’s physical and chemical integrity (Utah Code Annotated § 73-5-15). Generally speaking, however, environmental considerations in relation to groundwater quantity (i.e. seeking to maintain some portion of natural basin discharge that supports ecosystems) have not yet become a prominent consideration in setting basin-scale limits on extraction in the western US.
In Australia, macro-scale extraction limits are set by statute, usually through legislatively prescribed water planning processes. Broadly, two major goals of national water policy are “to increase the productivity and efficiency of Australia’s water use … and to ensure the health of river and groundwater systems by establishing clear pathways to return all systems to environmentally sustainable levels of extraction.” (Preamble, Intergovernmental Agreement on a
National Water Initiative
). National assessments of the progress of states in achieving these goals have repeatedly found shortcomings in relation to groundwater, however (e.g. National Water Commission 2009, National Water Commission 2011).
Australian water statutes generally cite both environmental and socio-economic objectives (e.g. section 3, New South Wales Water
Act 2000). They limit extraction in a basin to a level that reflects a combination of environmental and economic principles, with the balance between the two varying depending on the jurisdiction. The federal
Water Act 2007
gives an example of an environment-led limit: under that legislation, a legally binding federal management plan for the Murray-Darling Basin
requires states to ensure that aggregate groundwater pumping does not exceed “sustainable diversion limits” set to reflect “an environmentally sustainable level of take” (section 23). Key elements of that term, however, remain undefined in the legislation, and have been the subject of contestation. By contrast, the state of Victoria provides for “permissible consumptive volumes” to be set for groundwater administrative units without detailing the criteria to be applied to set these limits (section 22A, Water Act 1989), and they have not traditionally been set with regard to ecological water requirements. While Australian jurisdictions strongly emphasise the value of pre-planning acceptable extraction volumes, and constraining allocation through licences accordingly, some states do not impose allocation plans and general controls on groundwater extraction in basins that are only lightly exploited, preferring to wait until more intensive exploitation occurs before undertaking the technical work necessary to nominate extraction limits (e.g. prescribed water resources in South Australia: sections 76, 125, Natural Resources Management Act 2004).
In the EU, the Water Framework Directive sets a groundwater quantity goal of achieving “good quantitative status” for all water bodies by 2015. This will be achieved if the long-term annual average rate of abstraction is compensated by the aquifer recharge
. This definition is complemented by principles that go beyond traditional “safe yield
” concepts. The status definition also implies that the abstraction should not lead to alterations in flow directions which would result in saltwater or other intrusion. In addition, the level of groundwater should not be subject to anthropogenic alterations such that it would result in failure to achieve the environmental objectives (good chemical and ecological status) for associated surface waters, any significant diminution in the status of such waters, and any damage to terrestrial ecosystems which depend directly on the groundwater body. The policy framework opens the possibility for the Member States to use artificial recharge, providing that this does not jeopardise the quality of the groundwater.
As a general observation, to a greater or lesser degree, depending on the state, there seems to be a general movement towards basin-wide withdrawal limits that take some account of the impacts of extracting groundwater on the environment. This is quite a historical shift, which has generally mirrored the inclusion of such considerations in earlier surface water frameworks, or in a few cases occurred alongside it. This shift is proving much more advanced in Australia and the EU, at least on paper, than is the case in the western US, where often highly developed environmental protections for surface water are not replicated in relation to groundwater. The ease of modifying overarching principles through statute- and water plan-based processes may be one factor explaining this. Another might be the political difficulty of constraining economically important and water-intensive agricultural sectors in the western US, which have a much greater dependence on groundwater than does agriculture in most European countries or Australia (van der Gun 2013).
3.3 Micro Level Controls: Rights, Entitlements and Licences
Other than through basin-scale limits on extraction, the other major way in which groundwater law controls groundwater pumping is through rights, entitlements and licences at the scale of the individual groundwater user. Most jurisdictions within our focus regions require a person to obtain a right or entitlement to extract groundwater for particular end uses in all or many geographic areas. Notable exceptions to this are California and Texas in the western US, which do not generally require that a person obtain a permit to use groundwater, even for very large uses, except in small geographic areas. The requirements to obtain a permit or licence to use groundwater, and the processes involved, vary quite dramatically among our three focus regions, as well as within them (Patrick and Archer 1994; Bryner and Purcell 2003; Chapman et al. 2005; Gardner et al. 2009).
Western US groundwater allocation regimes tend to focus on a relatively narrow range of considerations that emphasise the human, rather than the environmental impacts of extracting groundwater. When considering an application for a permit, western US decision-makers commonly must consider: whether water is available for appropriation, the possibility of impairing existing rights, the applicant’s ability to put the water to immediate beneficial use, public interest considerations, which are often undefined, and water conservation considerations (e.g. Idaho Code § 42-203A). A third party usually has strong rights of review; often, they not only have the right to protest a licensing decision, but in doing so, trigger a public hearing on the matter (e.g. Idaho Code § 42-203A, Montana Code Annotated §§ 85-2-308, 85-2-309). However, mirroring arrangements in relation to basin-scale extraction limits, in very few jurisdictions are environmental matters explicitly mentioned as a groundwater permitting consideration (e.g. Montana Code Annotated § 85-2-311(3)(b)(vi), Idaho Administrative Code § 37.03.08.045(e)(ii); North Dakota Century Code, § 61-04-06(4)(c)), and in any case, it appears that these matters are rarely considered with great rigour in practice.
By contrast, Australian legislation tends to produce long lists of matters that a decision-maker must consider in determining whether to grant a licence, with a heavier focus on environmental impacts. A key consideration is whether granting the licence would be consistent with any applicable overall consumptive limit for the area or applicable management plan (e.g. section 147, Natural Resources
Act 2004 (South Australia); section 40, Water Act 1989 (Victoria)), which may itself contain further location-specific considerations relevant to licensing. Additional statutory considerations relate to the impacts on third parties of granting the proposed right to extract, and impacts on elements of the environment, such as water quality; water conservation policies; impacts on the aquifer structure (e.g. sections 40, 53, Water Act 1989 (Victoria)); and impacts on connected resources, discussed further below. Opportunities for the public to be involved in the issuing of groundwater licences—and the emphasis that agencies place on this form of participation—are often relatively limited, with most of the focus of public participation being at the water planning stage (Nelson 2013). This may be problematic where the effects of extracting groundwater—particularly ecological effects—are very localised, and likely able to be anticipated only by locals. Local-scale groundwater-dependent ecosystems (GDEs) are unlikely to have been captured in macro-scale planning processes, and are not guaranteed to be addressed by centralised decision-making (Nelson 2013). Recent efforts to map GDEs at a fine scale (Bureau of Meteorology (Australia) 2013) may go some way towards addressing this danger by making this information easily available to decision-makers and the public.
The relative paucity of western US legal arrangements in relation to water planning, basin-scale caps, and even the brevity of permitting considerations can be explained in part by its very different conception of the role of time, compared with Australia. Rather than focusing heavily on prospective caps or groundwater permitting considerations, western US groundwater law deriving from prior appropriation principles controls the impacts of groundwater extraction primarily by looking backwards. That is, it seeks to avoid over-pumping by curtailing the exercise of a groundwater right that has been found to impair an earlier water right. Dangers with this approach lie in the political difficulty of reducing established uses, and dealing with the time lags that can separate ceasing to pump groundwater and the remediation of adverse impacts.
In the EU, authority to pump groundwater is generally given through permits that refer to the quantity of water abstracted and/or pumping capacity. The permits are closely linked to the risks of not achieving the Water Framework Directive’s goal of “good quantitative status”, i.e. implying that the level of groundwater in the groundwater bodies is such that the available groundwater resource is not exceeded by the long-term average rate of abstraction. This implies that issued exploitation licences are operated in such a way that they comply with the good status objectives (i.e. restrictions may be imposed in case of water scarcity).
3.4 The Challenge of Exempt Uses
Permit or licence-exempt groundwater uses can be a significant governance issue, in that they escape many standard legal controls, and may pose a cumulatively significant draw on the resource. Dealing with the potential impacts of such uses has been a particular issue in the western US and Australia (Bracken 2010; Sinclair Knight Merz et al. 2010). The particular end uses that are exempt from the general requirement to obtain a permit or licence vary from place to place. Uses of groundwater for domestic use and livestock watering are an important use category that rarely requires a permit in Australia and the western US (Bracken 2010; Sinclair Knight Merz et al. 2010).
In addition to the problem of many small exempt uses, sometimes even large individual uses of groundwater are exempt from regular groundwater licensing or permitting processes. An important example is groundwater produced as a by-product of extracting coal seam gas, or CSG (also known as coalbed methane). CSG production has raised concerns in relation to its groundwater impacts in both the western US and Australia (National Research Council (U.S.). Committee on Management and Effects of Coalbed Methane Development and Produced Water in the Western United States 2010; Nelson 2012b). Petroleum and gas legislation in the Australian state of Queensland, where much of Australia’s CSG production occurs, explicitly enables CSG producers to withdraw an unlimited amount of groundwater as part of their CSG activities, without requiring a water entitlement (section 185(3), Petroleum and Gas (Production and Safety) Act 2004). The same position was recently reversed in Colorado after a state Supreme Court decision (Vance v. Wolfe, 205 P.3d 1165 (Colorado 2009)). Similar issues have arisen in other western states (Klahn and Tuholske 2010; Valorz 2010).
3.5 The Challenge of a Human Right to Water
Whereas exempt groundwater uses can challenge groundwater governance
by evading regular controls, nascent concepts of a human right to water could add further complexity to groundwater administration by conferring a different sort of special status on select groundwater uses. There are many areas of uncertainty in the meaning and practical implementation of a human right to water, in general (Good 2011). Regardless of the jurisdiction, key issues in relation to operationalising a human right to water will be its possible fiscal implications, the precise obligations that it creates, on whom, and how the right would be enforced (Thor 2013). A human right to water seems likely to attach to relatively small uses, like direct consumption and sanitation, which likely already benefit from permit-exempt status in many areas. Accordingly, new governance issues associated with the right seem more likely to be associated with groundwater quality
, than groundwater quantity. An exception to this might be situations in which large-scale groundwater pumping for other uses affects the availability of water sources that are used to satisfy the human right to water. In any case, a human right to water is an emerging issue which each of the focus regions will likely need to address in the future.
Internationally, various political statements acknowledge a “right to water”, including a resolution by the UN General Assembly (Thor 2013). Our focus regions take different approaches to this issue. There is no explicit reference to a human right to water in EU law but the first recital to the Water Framework Directive says “Water is not a commercial product like any other but, rather, a heritage which must be protected, defended and treated as such”, which is an implicit reference to human rights and principles of sustainability. Similarly, in Australia, a human right to water is not thought to be recognised at the federal level, but it has been argued that it could include principles of sustainability that would have a bearing on groundwater management, were it recognised (Good 2011).
California law has been more explicit. The state recently recognised a right to water in statute (Assembly Bill 685, codified as California Water Code § 106.3), though its formulation is relatively weak. AB 685 declares that it is state policy that every human being has the right to clean, affordable, and accessible water for human consumption, cooking, and sanitary purposes. However, the only duty that AB 685 imposes is a duty of “relevant” state agencies to “consider” the state policy on the human right to water when revising, adopting, or establishing policies, regulations, and grant criteria. It does not expand any state obligation to provide water, require the development of additional water infrastructure, or create an enforceable right for water system customers to demand immediate access to safe and affordable water. Though the precise legal implications of the law are not yet clear, recent focus on the lack of access to clean water of many disadvantaged communities in California, who rely on contaminated groundwater (Salceda et al. 2013), promises that it will be an important area of future legal development.
3.6 The Challenge of Connecting Groundwater Abstraction to Surface Water and Ecosystems
Integrating different elements of the environment, institutions, and actors is a noted challenge in water and environmental law (Klein 2005; Godden and Peel 2010; Thompson 2011). A particular challenge for groundwater law is how to deal with the relationship between groundwater and surface water—specifically, how abstraction of one should be controlled due to impacts on the other—particularly where these connections are affected by significant technical uncertainty. In general, the key issue is how groundwater pumping impacts rivers (though withdrawing surface water may also affect groundwater systems). A major related challenge is making legal provision for integrating groundwater with its environment, that is, making legal provision for ecological water requirements, thereby extending the now well-established concept of protected in-stream flows to groundwater. In most jurisdictions, this is an emerging and unsettled area of law, which seeks to address the water requirements of species and ecosystems that depend entirely on groundwater, as well as those that are associated with streams that receive water from groundwater-derived baseflow. The experiences of our focus jurisdictions demonstrate that key issues in determining a regulatory response to integrating groundwater, surface water and ecosystems will be determining trade-offs between using a complex, accurate, relatively certain, but administrative expensive mechanism (as in some states of the western US); and using broader, simpler, cheaper mechanisms, which offer arguably less certain results (as in Australia).
Western US mechanisms for integrating groundwater and surface water are arguably the most developed of the focus regions. They are also probably the most expensive to administer, since they require case-by-case technical assessments. Many western US states establish a threshold for the maximum proportion of the water withdrawn by a well that is predicted to be captured from a river over a certain period of time. States differ radically in the degree to which they will permit groundwater pumping to “impair” surface water rights. The relevant proportion in Colorado, for example, is 0.1 % of the annual pumped volume within 100 years of continuous withdrawal (Hobbs Jr 2010). Oregon, on the other hand, adopts a default threshold assumption that a well would usually cause substantial interference with a river if it is located less than a mile from the river, and derives 25 % of the withdrawal from the river within 30 days (Oregon Administrative Rules § 690-009-0040). States that have low regulatory thresholds for acceptable impairment of surface water rights tend to use flexible market-type mechanisms to enable groundwater pumpers to offset these impacts, and thereby meet the regulatory requirements for having their development proceed.
By contrast with protections for surface water rights, protections for (GDEs)
are at a very early stage of development in the western US. They are achieved chiefly by way of principle-based thresholds for impairment, such as a “public interest” test for granting a groundwater permit that can include protections for fish and wildlife (e.g. Idaho Administrative Code § 37.03.08.045(e)(ii), North Dakota Century Code § 61-04-06(4)(c)). With more development, the public trust doctrine—which in most states applies only to certain surface waters, rather than groundwater—could provide a promising route to protecting GDEs (Craig 2010; Spiegel 2010).
Protections for GDEs in the Blue Mountains, New South Wales
Not far from the suburban sprawl of Sydney, Australia, lie the Blue Mountains, which have attained World Heritage status on account of their biodiversity values, cultural values, geodiversity, water production, and wilderness values. A key threat to the area’s GDEs, particularly hanging swamps, comes in the form of new groundwater wells. The sensitivity of the ecosystems have warranted not only a ban on commercial wells in the Blue Mountains Sandstone Groundwater Management Area in 2007, but also short-term restrictions on the use of existing wells (NSW Office of Water 2011). Most significantly, given the generally high degree of reverence for domestic use of groundwater (see ‘The challenge of exempt uses’), the Water Sharing Plan for the Greater Metropolitan Region Groundwater Sources (Sydney Basin Blue Mountains Groundwater Source) bans the granting or amending of bore approvals within 100 m of listed, high priority GDEs in the case of “bores used solely for extracting basic landholder rights”, and 200 m for other uses; generally within 40 m from streams; and within 100 m from the top of an escarpment (clause 41).
Australian jurisdictions tend to use simpler volumetric or spatial thresholds to protect GDEs, such as clear drawdown limits or no-go zones for new wells around high-priority GDEs (see text box); or volumetric limits on groundwater pumping in a basin, where the limit is calculated to take into account acceptable impacts on rivers or other GDEs (Tomlinson 2011; Nelson 2013). In rare cases, caps on consumptive water use or rules that prevent extraction in response to water level triggers may cover both surface water and groundwater, where interaction effects happen over relatively short time-frames (e.g. Government of New South Wales 2010; Goulburn-Murray Water 2011). A further form of protection is offered by broad statutory considerations, such as requirements to have regard to environmental impacts when a decision-maker is considering a licence application (Nelson 2013). These approaches tend to require less case-by-case technical analysis than in the western US, but may offer less certain local protections, either because they apply at a macro level (e.g. large-scale volumetric limits), or because their requirements are not specified in detail (e.g. broad statutory considerations).
The EU’s Water Framework Directive addresses groundwater-surface water interactions by incorporating connections in its key goal: achieving “good quantitative status” implies that impacts of pumping groundwater should not result in alteration of status of associated surface waters or in any damage in groundwater-dependent terrestrial ecosystems. This regulatory mechanism is, in principle, well established. The extent to which it has been achieved will be evaluated in 2015 in consideration of these possible impacts.
3.7 The Challenge of Connecting Groundwater Abstraction Across Boundaries
In addition to integrating different water sources and users, groundwater
law frameworks also face the significant challenge of dealing with groundwater management in the cross-boundary context. This manifests, first, as rules for sharing cross-boundary aquifers; and second, as an allocation of responsibility for surface water depletions experienced in one jurisdiction, caused by upstream pumping of connected groundwater in another jurisdiction. Our focus regions illuminate several regulatory options for making these connections: proactive formal legal arrangements designed to prevent conflict, which may or may not involve creating a new regional institution; litigation to resolve conflicts; or, in some cases, a lack of coordinated management.
In the western US, litigation-based solutions to cross-boundary groundwater
issues tend to be relatively common, and pro-active formal legal arrangements, at least at the interstate level, fairly rare. In particular, the impact of pumping groundwater on interstate rivers has been a key issue subject to significant litigation. Lengthy litigation has dealt with how groundwater pumping affects surface water delivery obligations under multiple interstate agreements, which do not explicitly deal with groundwater (Hathaway 2011; Thompson 2011). In some cases, this litigation has resulted in multi-million dollar damages being paid by upstream groundwater pumping states to downstream states. Such litigation in some cases has been followed by comprehensive management arrangements that seek to avoid similar problems recurring, including integrated surface water-groundwater technical models and monitoring programs. This litigation has proven to be a key driver of intrastate efforts to integrate the management of groundwater and surface water (Nelson 2012a).
Although litigation-based management of transboundary groundwater-surface water resources has proven the norm in the western US, the recent agreement between eight US states and two Canadian provinces governing management of the Great Lakes, and connected groundwater and tributaries takes a promising, different approach (Great Lakes-St. Lawrence River
Water Resources Compact, effective 2008). The Compact applies to “Waters of the Basin”, which are defined to include tributary groundwater (Article 103). The Compact establishes a central authority for management and implementation, and applies a common “decision-making standard” in relation to signatories regulating water uses within their territories (Article 203), but at the same time, grants them a relatively high degree of autonomy (Hall 2006).
In shared groundwater basins in the western US, which lack the complexity of highly connected surface water, “divided administration is the status quo” (Davenport 2008). Major interstate aquifers, like the High Plains Aquifer System (which includes the Ogallala Aquifer) underlying parts of South Dakota, Nebraska, Wyoming, Colorado, Kansas, Oklahoma, New Mexico, and Texas, are administered by each state under separate arrangements. There is no formal coordination of the sort found in interstate river basin commissions or compact arrangements (Sophocleous 2010; Hathaway 2011), and no Supreme Court litigation to apportion the groundwater (Leshy 2008a). Rather, a situation of “de facto groundwater allocation” through “a combination of unilateral actions and lack of action” occurs in many basins, for example the Hueco Bolson Basin underlying New Mexico, Texas and Mexico; in others, some mechanisms like data sharing exist, but cooperation is notably lacking (Hathaway 2011, p. 106). Commentators have noted that interstate groundwater conflicts are developing, particularly where groundwater use is growing (Hathaway 2011).
Australia’s management challenges in relation to transboundary aquifers are relatively simple, since it lacks international groundwater boundaries and has relatively few states. The most significant aquifer that crosses interstate boundaries is the Great Artesian Basin, the world’s largest artesian basin (Mackay 2007). Coordinated management of the basin occurs under the Great Artesian Basin Coordinating Committee, which has a largely advisory role, rather than regulatory functions. Its main focus has been a scheme to fund the capping of artesian wells that previously were allowed to run freely, causing a loss in aquifer pressure (Mackay 2007). At a smaller scale, a groundwater border agreement between the states of Victoria and South Australia, for example, controls depletion of a non-recharged aquifer by bores other than stock and domestic bores by setting zone-based caps on extraction and drawdown (Schedule 1,
(Border Agreement) Act 1985 (Victoria)). It takes effect through state-level licensing decisions within a 40 km-wide cross-border area of the aquifer, which must be made consistent with the Agreement.
The EU Water Framework Directive deals with interjurisdictional groundwater issues in a notably more proactive and structured way than has been the case in either Australia or the western US. It requires Member States to establish international river basin districts, thus requiring cross-boundary cooperation for overall water management, including groundwater (article 13, items 2). It also recommends Member States to establish appropriate coordination with non-EU countries in river basins crossing the boundaries of the EU (this is however not as strict as the first regulation, as the article says: the Member States “shall endeavour to establish cooperation”) (article 13, item 3). This is the only reference to cross-boundary aquifer situations concerning quantity aspects. In addition to this, the Groundwater Directive (daughter directive to the WFD) requests Member States to coordinate the establishment of threshold values (groundwater quality
standards) in bodies of groundwater within which groundwater flows across a Member State’s boundary. Similarly to the WFD, it also recommends (“shall endeavour”) coordination with non-EU countries sharing a transboundary aquifer for the establishment of groundwater quality standards (threshold values).