TILL THE GROUND TO SEE THE CLOUDS: GOVERNANCE CHALLENGES AND GROUNDWATER DEMAND IN THE SAN PEDRO RIVER TRANSBOUNDARY AQUIFER AND THE AMERICAN SOUTHWEST by Robert Dan Agler BA, Kutztown University of Pennsylvania, 2015 Submitted to the Graduate Faculty of Department of Environmental and Occupational Health Graduate School of Public Health in partial fulfillment of the requirements for the degree of Master of Public Health University of Pittsburgh 2018 UNIVERSITY OF PITTSBURGH GRADUATE SCHOOL OF PUBLIC HEALTH This essay is submitted by Robert Dan Agler on August 9, 2018 and approved by Essay Advisor: James Peterson, PhD Associate Professor Department of Environmental and Occupational Health Graduate School of Public Health University of Pittsburgh Essay Reader: Brian Thomas, PhD _ Assistant Professor Department of Geology and Environmental Science The Kenneth P Dietrich School of Arts & Sciences University of Pittsburgh ii Copyright © by Robert Dan Agler 2018 iii James Peterson, PhD TILL THE GROUND TO SEE THE CLOUDS: GOVERNANCE CHALLENGES AND GROUNDWATER DEMAND IN THE SAN PEDRO RIVER TRANSBOUNDARY AQUIFER AND THE AMERICAN SOUTHWEST Robert Dan Agler, MPH University of Pittsburgh, 2018 ABSTRACT Groundwater is a concern of public health significance often not discussed in the United States (US), because it has yet to make it into news reports and capture national attention It is, however, a very real issue for populations living in already water-scarce environments like the American Southwest, which relies on aquifers for its freshwater supply This study evaluates the classification of the binational San Pedro River Transboundary Aquifer (SPRTA), which is partially located in the US state of Arizona (AZ) and the Mexican state of Chihuahua The evaluation includes a review of the literature related to international law and the transboundary nature of an aquifer, groundwater governance and management, and stakeholder engagement While the SPRTA is shared between the US and Mexico, this study mostly focuses on the American side of the SPRTA, because an English translation of most resources provided by the Mexican government was not available; the international nature of the SPRTA, however, is not ignored Criteria for determining a transboundary aquifer’s priority status for research was outlined under the Transboundary Aquifer Assessment Act (TAAA), which the US Congress passed in 2006 Broad analysis focuses on groundwater demand by county, county population, and geologic features, such as earth fissures and land subsidence, in the US states of AZ, New Mexico (NM), and Texas (TX) to help evaluate the utilization of and impact on groundwater resources Land subsidence and earth fissures in AZ are concentrated in Maricopa, Pinal, and iv Cochise Counties (Co.) In Cochise Co., farms overlay areas of land subsidence, which attributes groundwater overdraft to agricultural demand This study identifies counties with the largest groundwater demand in AZ, NM, and TX by providing a spatial analysis of groundwater demand by county Geologic features, like land subsidence and earth fissures, demonstrate groundwater overdraft in Cochise Co Results showed just one AZ county (Maricopa Co.) accounted for 2842% of total groundwater used per day in the state By contrast, TX counties seldom consumed more than 1.4% of total groundwater per day, which could be attributed to the large number of counties in the state The results of this study will help to promote better management practices of groundwater in the SPRTA and other transboundary aquifers in a top-down system, while considering satisfactory stakeholder engagement This study concludes by recommending the Mesilla aquifer as the next priority transboundary aquifer to be studied by the International Boundary & Water Commission (IBWC) and both the US and Mexican governments v TABLE OF CONTENTS ACKNOWLEDGEMENTS VIII 1.0 INTRODUCTION 2.0 LITERATURE REVIEW 2.1 INTERNATIONAL LAW & THE TRANSBOUNDARY NATURE OF AN AQUIFER 3.0 2.2 GROUNDWATER GOVERNANCE & MANAGEMENT 2.3 STAKEHOLDER ENGAGEMENT 15 2.4 ANALYSIS 17 CONCLUSION .25 APPENDIX: LISTED TRANSBOUNDARY AQUIFERS UNDER TAAA 29 BIBLIOGRAPHY 30 vi LIST OF FIGURES Figure 1: Percent consumption of groundwater by county per day relative to total county population 19 Figure 2: Groundwater demand by county, location of cities, and recorded land subsidence and earth fissures across the state .21 Figure 3: Location of farms relative to land subsidence in Cochise County .23 Figure 4: All priority transboundary aquifers identified under the Transboundary Aquifer Assessment Act .29 vii ACKNOWLEDGEMENTS I would like to thank my parents, Michael and Juliana Agler, for their enduring support and faith in my abilities I would also like to thank my readers, Dr James Peterson and Dr Brian Thomas, and the faculty of the Department of Environmental and Occupational Health for their guidance throughout the MPH program and essay Lastly, I would like to thank my partner, Arren Dawinan, for his endless patience and support, as I pursued my dreams in obtaining a Master of Public Health viii 1.0 INTRODUCTION As average global temperatures continue to rise, governments will increasingly rely on groundwater as a meaningful source to sustain their populations and meet society’s water demands during tumultuous periods as in times of drought or natural disaster (Famiglietti et al., 2014) In fact, climate change is projected to affect the recharge rates of both groundwater and surface waters in the American Southwest (SW) especially, which would make water resources a more valuable commodity in the future than governments and their populations realize, and this, along with other considerations, threatens peace and prosperity among and between neighboring countries (Ajami, et al., 2017) In their study, researchers found the SW would suffer the lowest recharge rate (27 mm per year) of any region in the US (Ajami et al, 2017) Another study demonstrates the fragility of groundwater resources in the SW, where precipitation events greatly impact groundwater recharge, but whether recharge dependence on precipitation is due to climate change or climate-scale variability remains unknown (Behrangi, Famiglietti, Thomas, 2016) With this in mind, the need to survey and evaluate groundwater resources in the SW is doubly important, since it is such a critical resource In its Draft articles on the Law of Transboundary Aquifers, the United nations (UN) defines “aquifer” as “a permeable water-bearing geological formation underlain by a less permeable layer and the water contained in the saturated zone of the formation,” and a “transboundary aquifer” is “an aquifer or aquifer system, parts of which are situated in different States,” or nations (United Nations, 2008) Of the multitudinous transboundary aquifers identified—estimated in the hundreds—fewer than 10 are governed by a management agreement between participating states or nations (Walton, 2016) The SPRTA is a recently studied aquifer thanks to its priority status under the Transboundary Aquifer Assessment Act (TAAA), and it is located in the SW region (Appendix), where recharge under differential levels of precipitation and other shifting climatic conditions poses a risk in the future The International Boundary and Water Commission (IBWC) published the San Pedro River Aquifer Binational Report in early 2016, a collaborative effort between the US and Mexican federal governments that studied the SPRTA In addition to the significance this report means for groundwater research in the SW, it is also an exercise in international cooperation of non-navigable waters between neighboring countries Groundwater in the SPRTA is shared between Cochise Co in the US state of AZ and the Mexican municipalities of Naco and Cananea in the state of Sonora Cities located within Cochise Co and Sonora utilize groundwater for different purposes According to groundwater use data from the US Geological Survey (USGS) from 2010, about 90.07% of daily groundwater withdrawal in Cochise Co is used for irrigation purposes, while most groundwater withdrawal in Sonora is for “industrial (the Cananea mine), and public-urban” supplies to communities throughout the Mexican state (Callegary, et al., 2016) The use of groundwater for industrial purposes has the potential to contaminate the aquifer and also cause an overdraft of the aquifer, and this could adversely impact populations in both countries The binational report revealed discrepancies in database management between the US and Mexican researchers and water managers as well as a lack of understanding of an aquifer system by the UN.Is the priority status of the SPRTA under the TAAA a meaningful designation, or would other aquifers serving larger populations benefit from priority status? It merits the Figure 1: Percent consumption of groundwater by county per day relative to total county population The map shows percentage of domestic supply of groundwater use and total population by county for the three US states implicated in the Transboundary Aquifer Assessment Act passed by Congress in 2006 This reveals parts of states where populations rely more on groundwater than other counties In TX, for example, there are some counties northwest in the state who rely on groundwater, but the vast majority of the state does not rely a great deal (0-1%) on groundwater By contrast, counties in New Mexico demonstrate greater dependence on groundwater, and those counties are clustered in the center and southeast of the state In AZ, Maricopa Co is responsible for 28-42% of total groundwater use The figure also shows reliance on groundwater for counties bordering Mexico This could be useful to counties that host large 19 metros like Maricopa Co does the city of Phoenix Observations of Figure underlines that certain counties—and sometimes groups of counties across states (e.g., border counties between NM and TX)—rely more on groundwater than others The preponderance of fragmented authority fits the US, since it enables local municipalities to establish their own policies on groundwater, but the increase of legal frameworks as a result ignore the impact that groundwater overdraft has on the environment Some consequences of groundwater overdraft include land subsidence and earth fissures The United States Geological Survey (USGS) defines land subsidence as a “gradual settling or sudden sinking of the Earth’s surface owing to subsurface movement of earth materials” (United States Geological Survey Office of Groundwater, 2017) In his 1975 landmark study on the subject, Joseph Poland identified four causes of land subsidence, which are: due to declining water levels, hydrocompaction of soils lacking moisture, extractions from oil and gas fields, and tectonic settling (Ireland, Lofgren, Poland & Pugh, 1975) Researchers established an association between groundwater overdraft and the occurrence of land subsidence, but this sinking of the planet’s surface can grow more extreme to form earth fissures These are “small hairline cracks in the subsurface” either along a basin’s edge or near shallow bedrock (Conway, 2016) Besides earth fissures, land subsidence can also influence natural drainage patterns and floodplains, and it also affects the matrix packing alignment, which affects hydrogeologic characteristics and results in reduced permeability and hydraulic conductivity Compressing space within aquifers, where groundwater flows, could lead to permanent loss of groundwater storage (Conway, 2016) The occurrence of land subsidence and earth fissures coincide with counties in AZ that rely on groundwater more than others, and this could result in damaged infrastructure (subterranean pipes for water/gas) and property damage whose price is a costly exercise in mitigation 20 Figure 2: Groundwater demand by county, location of cities, and recorded land subsidence and earth fissures across the state For example, the majority of fracturing of the earth’s surface in AZ is spread across Maricopa, Pinal, and Cochise Cos., where massive amounts of groundwater are especially utilized in Maricopa Co The occurrence of both land subsidence and earth fissures in Cochise Co are observed in the north central and northeast portions between Cochise and Graham Cos., where the Willcox groundwater basin is located Conway makes no mention of the SPRTA in his study While overdraft of the Willcox groundwater basin possibly contributed to land subsidence, what is the hydrologic relationship between this basin and the SPRTA, if any? The issue, then, is not only the lack of concern for groundwater-environment interactions but also the flow of groundwater across (and possibly between) adjoining aquifers A group of researchers created the 21 Environmental Water Demands database for AZ in order to fill this gap in knowledge on environmental flow needs and responses as they relate to different ecosystems with varying degrees of reliance on groundwater (Lacroix, Xiu, Nadeau, Megdal, 2016) The database seeks to aid management decisions by informing them of interactions previously mentioned, which could in turn help managers understand future impacts of present decisions However, these issues and their proposed solutions fail to reach the context of binational cooperation, where a greater degree of nuance exists for counties that border Mexico and share an aquifer with a neighboring state in Mexico The need to understand groundwater use in a binational context between the US and Mexico cuts across all disciplines studying groundwater governance and use If a relationship between the Willcox groundwater basin and the SPRTA exists, it could add greater context for land subsidence and earth fissures reported in Cochise and Graham Cos The transboundary nature of the SPRTA serves as a point of contention, because studies of the aquifer consistently fail to incorporate data and research of the SPRTA by Mexican institutions and researchers In fact, the lack of synthesized data and research of the SPRTA from both American and Mexican sources was listed as a limitation in the binational report on the SPRTA (Callegary, et al., 2016) Creators of the Environmental Water Demands database envision the database as a resource crucial to water management, because it would serve as a “one stop shop for identifying critical geographic and topical knowledge gaps” (Lacroix, Xiu, Nadeau, Megdal, 2016) These gaps in knowledge, however, are attributed to environmental flow rates of groundwater This database is an important development, but it would be more beneficial to managers and researchers if the database included a reference tool to identify stakeholder preferences and different legislation governing each aquifer This is in line with the knowledge generation and dissemination 22 component of the groundwater sustainability index generated by a group of researchers; this generation and dissemination “helps build mutual trust among the stakeholders to achieve the goal of sustainability” (Pandey, Shrestha, Chapagain, & Kazama, 2011) Adding these could aid informed decision-making by showing all the legislation governing a single aquifer or basin, and this, in turn, could hopefully prevent the formation or worsening of land subsidence Figure 3: Location of farms relative to land subsidence in Cochise County Based on data from the USGS Estimated Use of Water in the United States County-Level Data, groundwater in Cochise Co is mostly used for irrigation (about 215 Mgal/day), public supply (about 16 million Mgal/day), and thermoelectric power (about Mgal/day) The state of Sonora, Mexico relies on groundwater largely for industrial purposes (Callegary, et al., 2016) Given the majority use of the SPRTA for agricultural and industrial purposes, is it likely this 23 elastic response is likely to continue, until it becomes inelastic and land subsidence begins to occur in this densely populated part of Cochise Co.? Despite observations of land subsidence, Figure shows more counties (11) in NM rely on groundwater (2-14%) as opposed to AZ, where all but one county utilizes 1-14% of total gallons of groundwater used per day This information is important to help evaluate the criteria used by the US Congress for classifying a transboundary aquifer as “priority” for research in the TAAA The second criterion on the extent of use of a transboundary aquifer fits the Mesilla Aquifer, since it underlies groupings of NM counties with moderate to high use of groundwater relative to other counties in the state (United States Congress, 2006) It is difficult to fully understand the transboundary nature of aquifers considering the large number of dependent factors, like groundwater use and infrastructure, total population, aquifer boundaries, etc The classification of and binational study on the SPRTA is sensible, since industrial activities in Sonora could affect water quality on the US side of the aquifer Potential land subsidence near the San Pedro River, where a number of farms are located, serves as another good reason to study the SPRTA A larger number of NM counties may rely on the Mesilla Aquifer As a result, large numbers of legal frameworks could have emerged on groundwater governance of the Mesilla Aquifer, which underlies a cluster of moderately to highly populated counties It thus fulfills the first criterion for identifying priority transboundary aquifers, which is the aquifer’s proximity to areas of high population density (United States Congress, 2006) However, it is unclear to which activities groundwater contributes more among NM counties, and commentary here on the aquifer’s susceptibility to contamination, the third criterion, would amount to conjecture 24 3.0 CONCLUSION Groundwater is an invisible resource that southwestern states in the US increasingly rely on to meet all water demands However, it eludes some portions of the Southwest, and interest in transboundary groundwater is especially neglected, considering few binational agreements managing transboundary aquifers exist The transboundary nature of the SPRTA takes into consideration physical (extent and properties) and socio-cultural (social, economic, etc.) information, and this follows the decentralized nature of groundwater management across the US Groundwater in Cochise Co., which is situated above the SPRTA, is used mostly to serve the Fort Huachuca military base and also for domestic and agricultural purposes Some instances of land subsidence and earth fissures have been documented in the central and northern parts of the county and are displayed in Figures and The transboundary nature of aquifers, especially the SPRTA, is inextricably tied to groundwater governance and management Governance of these resources is characterized by fragmented authority across the US, for which decentralized management is a feature This fragmentation was demonstrated from the literature review, where Megdal and others characterized groundwater governance across the US as fragmented (Megdal, Gerlak, Huang, & Varady, 2014) Other researchers have also classified boundary organizations that govern groundwater as resembling fragmented authority (Larson, White, Gober, & Wutich, 2015) In the 25 analysis section, fragmented authority governing groundwater was shown to be beneficial to local municipalities, when setting their own water agendas However, this characterization results in multiple legal frameworks and challenges binational cooperation Additional studies (e.g Megdal et al., 2014; Larson et al., 2015) further support the characterization of authority over groundwater as fragmented On stakeholder engagement, researchers strongly favor a co-production of knowledge among different constituencies The creation of AMAs in AZ is an example of stakeholder engagement (Hess et al., 2016), and while technical workshops and public conferences on AMAs were held to build rapport and cooperation among constituencies, this exercise in stakeholder engagement oftentimes fails to address needs of ecosystems that also depend on groundwater (Hess et al., 2016) Groundwater in three southwestern states (AZ, NM, TX) was analyzed by county for percentage use of groundwater and total populations in addition to discussions on fragmented authority and multiple legal frameworks related to governance and management of aquifers In this analysis, some discussion focused on overdraft of groundwater past a threshold in which clay and rock layers become inelastic and cause land subsidence and earth fissures Cochise Co., where the SPRTA is located, uses little groundwater compared to Maricopa Co., but it is nonetheless classified as a priority transboundary aquifer by the US government The broad stretch of documented land subsidence and earth fissures across three counties (Maricopa, Pinal, Cochise) is more an indication of dependence on rather than use of groundwater In total, analysis drew attention to important elements related to the SPRTA for future research, which include observations on the Mesilla aquifer [Appendix] 26 The SPRTA is correctly classified “priority” for research, because it met all criteria for evaluating transboundary aquifers under the TAAA Its transboundary nature is appropriate as a preliminary binational study, since it only underlies Cochise Co and its transboundary nature is less complex than other priority transboundary aquifers The SPRTA binational study was an exercise in cooperating on research and developing databases for use by both countries Cochise Co There are, however, local issues the TAAA does not consider in its selection of transboundary aquifers for research While no study links groundwater overdraft of the SPRTA to land subsidence or earth fissures in southwestern Cochise Co., those issues are nevertheless endemic to the central and northeastern portions of the county Land subsidence also reaches into Hidalgo Co., NM, based on Figures and 3, and Hidalgo Co accounts for just 1% of total groundwater use per day in NM US states must also cooperate on groundwater research and use The Willcox aquifer, to which overdraft and land subsidence have been associated, also has a transboundary nature that has been underrepresented in the literature Given this observation, TAAA criteria should also include consideration of land subsidence and earth fissures, which should include evaluating the potential or extent of development of both; broad classifications could be based on length or depth of event A number of contradictions arise in regulatory frameworks—from fragmentation to accurate records of groundwater use and overdraft—that are crucial to binational studies of transboundary aquifers Fragmented governance over groundwater may aid local municipalities in setting their own water agendas, but it may also ignore the ecological consequences involved By comparison, the US Congress, in assigning priority status to transboundary aquifers, ignored the scope of groundwater reliance by state More counties in NM generally rely on groundwater 27 than counties in either AZ or TX NM counties may be less densely populated, but their reliance on groundwater from the Mesilla aquifer underlines the significance of this resource to the general NM population By contrast, the majority of groundwater in AZ is utilized by just one county (Maricopa Co.) The Mesilla aquifer underlies Dona Ana Co in NM and El Paso Co in TX, and of these two, the binational report would be of more importance to Dona Ana Co., since El Paso utilizes less groundwater Additionally, the Mesilla aquifer would be an exercise in following the different types of frameworks established during the SPRTA binational report, but it remains to be seen whether the presence of El Paso Co (TX) would be a challenge to the framework and future legislation, given its relatively negligible dependence on groundwater Considering these factors, the transboundary nature of the Mesilla aquifer would be an important study for the IBWC and US and Mexican national governments to conduct, and it would help inform the literature on fragmented authority and legal frameworks established under the SPRTA 28 APPENDIX: LISTED TRANSBOUNDARY AQUIFERS UNDER TAAA Figure 4: All priority transboundary aquifers identified under the Transboundary Aquifer Assessment Act Source: Transboundary Aquifer Assessment Program, Water Resources Research Center, The University of Arizona 29 BIBLIOGRAPHY Ajami, H., Bhattarai, N., Castro, C., Dominguez, F., Gochis, D., Meixner, T., Niraula, R., Rodell, M (2017, October 16) How Might Recharge Change Projected Climate Change in the Western U.S.? 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THE CLOUDS: GOVERNANCE CHALLENGES AND GROUNDWATER DEMAND IN THE SAN PEDRO RIVER TRANSBOUNDARY AQUIFER AND THE AMERICAN SOUTHWEST Robert Dan Agler, MPH University of Pittsburgh, 2018 ABSTRACT Groundwater. .. assess the binational effort to characterize and study the SPRTA to better understand factors and challenges related to the binational study’s successes According to this study, the TAAP defines... with a neighboring state in Mexico The need to understand groundwater use in a binational context between the US and Mexico cuts across all disciplines studying groundwater governance and use If