Reflections: Exploring Karst Groundwater Vulnerability and Risks in Arizona in 2021
Groundwater is among the world’s most important natural resources. It provides drinking water to rural and urban communities, supports agriculture and industry, sustains wetland and riparian ecosystems, and maintains the flow of rivers and streams. In many places, groundwater resources are susceptible to risks of overuse and contamination. Its sustainable management is increasingly critical; especially in climate-sensitive geographic areas such as islands and arid lands.
My main interest is in researching karst groundwater sustainability because aquifers storing groundwater in karst systems are commonly found throughout my home country, Jamaica, and other islands in the Caribbean. Karst aquifers are formed mainly by water dissolving and forming characteristic features such as sinkholes, caves, and cracks in the bedrock. Figure 1 shows the typical features of karst aquifers.
Figure 1: Features of karst groundwater systems.
In Arizona, the major karst aquifer system is found in the north in the Coconino Plateau area; which includes the city of Flagstaff, and the Grand Canyon region. The physical characteristics of karst groundwater systems make them highly susceptible to pollution and climatic influences. As shown in Figure 2, physical features of karst landscapes, such as sinkholes, act as quick pathways for pollutants to be transported to the aquifer, given that there are little or no soil layers to filter pollutants en route to the aquifer.
Figure 2: Illustration of karst groundwater aquifer contamination
Ensuring sustainable water supplies requires an understanding of underlying hydrologic and geologic processes, but also socioeconomic factors that drive impacts on water resources, including land use, demand management, and the population involved. It is important to know and understand how characteristics of the natural system and population priorities interplay with resource availability, demand, land use, and other socioeconomic characteristics of the area to influence the sustainability of water. Because ground-water systems typically respond slowly to human actions, a long-term perspective is needed to manage this valuable resource. This is especially so given forecasted impacts of climate change and variability impacts on water resources.
Water is the main medium through which climate change will impact ecosystems, economies, and people. Climate variability and change affect all aspects of water. The general impacts on freshwater quantity and quality are expected to be negative. While the influences of climate variability and change on water show general consistency across countries, there are important regional and local differences. Some of these differences remain undetermined. The impact of climate change on water resources depends not only on the climate itself but also on the characteristics of the groundwater system, changing pressures on the system, how the management of the system evolves, and what measures to adapt to climate variability and change are implemented. Therefore, the degree and extent of the projected impacts of climate change on water resources across time and space serve as a strong incentive to ensure appropriate adaptation to minimize the negative effects.
In Arizona, water management is influenced by a complex mix of geographic, hydrologic, climatic, and regulatory factors. Also, information about water resources is not homogenous and tends to be more available for highly populated Active Management Areas (AMAs ) in the alluvial groundwater basins, than rural, karst groundwater systems. Water sector actors in rural, karst areas are hampered by a lack of information to inform sustainable management of the resource. Therefore, my research objective for the fellowship year was to conduct exploratory research to become familiar with the interplay among various factors, and a karst groundwater system, to inform the design of an empirical study for my dissertation. Basically, I seek to learn from the example of Arizona’s karst groundwater systems. During the past year, I proposed to collaborate with stakeholders tackling groundwater sustainability issues to gain some understanding of the local groundwater system and factors driving its vulnerability and contamination risk. I collaborated with the Coconino Plateau Watershed Advisory Council (CPWAC) and Coconino Plateau Watershed Partnership (CPWP), which together involves 34 local, state, tribal, federal and civil society organizations that represent varied stakeholders interested in preserving regional water resources.
Research design and methods
A mixed-method, use-inspired approach was applied to facilitate understanding of local water stakeholders’ needs and issues. Such understanding is important for designing empirical research that yields outputs and outcomes that will be readily useable by stakeholders. The mixed-methods employed included: 1) review of existing literature and information databases; 2) data mining pertaining to factors that are relevant for identifying groundwater vulnerability, and risk; 3) conducting key informant interviews; and, 4) field observation to characterize the regional groundwater management context. The approach to the study was highly consultative; with stakeholders engaged at all stages. During the design phase, the project was discussed with the primary stakeholder and the terms of engagement and collaboration during project implementation were agreed upon with the stakeholder. The methodology also considered exigencies of the unique period we are all trying to navigate with the enduring COVID-19 pandemic.
Figure 3: Map of Karst Groundwater Aquifers in Coconino Plateau Region (Adapted from BLM (2015)
The study targeted the groundwater in the Coconino Plateau region of Arizona. The study area has a high physical water scarcity  or socioeconomic water scarcity . The roughly 5,000 mi2 Coconino Plateau falls within the Upper Colorado River Basin and contains a complex regional groundwater aquifer system. The aquifer system is an increasingly important source of water supply for domestic, municipal, and in-stream uses owing to rapid population growth and development. The karst groundwater resources are shown in Figure 3 and consist of several perched water-bearing zones , a regionally extensive sandstone aquifer, and a limestone aquifer. The characteristics of groundwater flow within the regional aquifer are poorly understood because the aquifer is deeply buried; which limits exploratory drilling and testing to study system properties. Also, the geologic structure, that controls the occurrence and movement of groundwater, is complex. The underlying structure and hydrogeological behavior of these karst aquifers make them highly susceptible to pollution. Water can move rapidly through karst conduits and the overlying soil is very thin, or absent; making the protection of karst groundwater systems a high priority.
Local stakeholders have raised concerns about the effects of development on the availability and sustainability of groundwater water supplies. They agree that an improved understanding of the regional socioeconomic and hydrogeologic system is needed to address the concerns of water supply and groundwater sustainability. Such an understanding requires a comprehensive baseline of information that adequately describes the system. However, this baseline information is incomplete at best for the Coconino Plateau region. I am especially interested in understanding how land use combined with natural karst system characteristics are driving contamination of the groundwater, and how water pollution is behaving across time and space under changing climatic conditions. For instance, there is a higher presence of private wells being used as the primary source of domestic water supply in rural areas of the basin; unlike the more technologically advanced water supply systems in urban areas. As illustrated in Figure 2, because of the physical features of karst systems, high levels of private well used for domestic water supply may pose a risk of groundwater contamination along with negative human health impacts due to exposure to contaminated groundwater. This is particularly so when combined with low-technology household wastewater treatment systems and other improper waste disposal practices.
Stakeholders also identified mining activities and inadequate regulations of such land use as potential sources of groundwater contamination risks. While regulators were poised to grant a permit for mineral mining, I learned from stakeholders that their review of a mine operator’s voluntary monitoring data suggests that contaminated water from the mining operation may be adversely affecting groundwater quality via transport to the karst aquifer through subsurface rock fissures. This may point to disparities in the level of regulatory protections and outcomes available for alluvial versus karst aquifers, and rural versus urban groundwater resources. While the literature highlights the pioneering work and example of Arizona’s groundwater regulations, stakeholders in this predominantly rural, karst region are actively advocating for regulatory change to better protect their local groundwater resources. This example illustrates that gaining an understanding of these issues within the regional context will provide critical information to address system-wide sustainable management of karst groundwater. It gives an indication of potential areas for targeted preventive or remedial action; especially given the reliance on private well sources of potable water in rural karst areas. Such knowledge can also inform different approaches that may be necessary to improve karst groundwater management versus applying the same approach to all aquifers statewide.
Some outputs and outcomes
Beginning in October 2020, I participated in several stakeholder meetings to develop familiarity with the different stakeholders, their water issues, and engagement processes. This included a subcommittee meeting focused on public education and outreach, which became a key point of engagement for the collaborative research. Because of the pandemic, stakeholder meetings were fully virtual. This made my participation more feasible, given the significant distance between Tucson in the south and Flagstaff in the north where stakeholder meetings were convened. Stakeholders prioritized the development of a story map to sensitize the public on existing initiatives implemented or being pursued by CPWAC partners. They shared existing data and information. I also conducted some key informant interviews with some stakeholders to gain insight into individual stakeholder priorities, processes, factors affecting water resources, and competing stakeholder priorities.
Although the COVID-19 pandemic limited in-person contact, towards the end of the year I was able to go into the field briefly to get a sense of the landscape, resources, and general characteristics of the Coconino Plateau region. This was an important introduction to arid region karst; given I am well aware that not all karst is the same. Familiar, tropical island karst will likely display nuanced differences from karst in arid lands. I collected and collated material for a water sustainability story map, designed a geodatabase, and commenced populating the database with secondary data relating to regional karst groundwater vulnerability. This work assists with building local water stakeholders’ capacity by supporting the development of information products and tools to enhance advocacy, public awareness, and understanding of karst groundwater management issues in the Coconino Plateau region.
A major outcome of this use-inspired research process has been the knowledge I acquired from direct engagement in stakeholder activities and interaction with individual stakeholders in the Coconino Plateau region. I learned about the water sustainability priorities of more rural stakeholders; priorities that varied from those of stakeholders in relatively urban AMAs designated by Arizona’s main groundwater regulation. For instance, I benefited from consultation with a farmer who was very concerned that farming is viewed as being unsustainably practiced due to excessive amounts of groundwater being used. As a result, I became aware of agricultural stakeholders’ priorities for sustaining water supplies. In the AMAs, larger cities and agricultural operations can get through dry spells by accessing groundwater reserves or bringing water from other locations such as the Colorado River. But, rural, non-AMAs areas in karst regions are less prepared. Instead, there is heavy reliance on wells that can easily malfunction or run dry. As long-term drought conditions continue to affect the region, rural communities are eager to find solutions. While they have no way to immediately stop the unusual dryness, they are taking action through sustainable on-farm practices that can function as a buffer. So, from my interaction with this farmer, I learned about some on-farm water management practices being utilized to reduce groundwater depletion in the region. This includes rainwater harvesting, using recycled material in farm water management, and restoring vegetation (see Figure 4) which has the ability to absorb water in the soil, and to hold deeper, longer-lasting reserves of water, while providing shade to protect animals from heat stress. The direct engagement produced an understanding of locally important issues that until then I had not identified.
Figure 4: On-farm water management practices: L-R - rainwater harvesting, recycled tires as water troughs, and reforestation.
The research provided multiple opportunities for cross-learning between karst aquifers in arid regions and island states in the Caribbean. Importantly, collaborative stakeholder engagement enabled a comparison of karst groundwater management issues, institutional arrangements, and stakeholder dynamics in this arid region with that of tropical island karst groundwater problems. It provided knowledge and learning about potential stakeholder dynamics and competing priorities at play in multi-stakeholder efforts to protect groundwater resources. I gained insight into the informal networks/connections and stakeholder dynamics that is very important for researchers to know and navigate when doing use-inspired research. It is also an important point of understanding when interpreting research findings, or when making recommendations for future research, policy design, and management actions.
I noted that having a diverse range of participants in a stakeholder group that is seeking to address water resource issues is helpful in advancing action. It also aids a researcher in getting multiple views of issues and priorities in a short period of time. For instance, there are several native nations within the region. Noticeably, having indigenous people represented within the larger stakeholder group enabled a two-way dialogue on issues that affect indigenous people, who are often overlooked in water governance decision-making. Inclusion also provided an opportunity for non-indigenous stakeholders to incorporated these considerations into their operations. For one, there was an initiative for the council/partnership (and individual stakeholders) to adopt a statement acknowledging the contribution of native nations and people to sustaining the benefits of regional water resources. Often such statements lay a foundation for subsequent actions and partnerships to tackle issues that disproportionately affect indigenous people. Another observation made is that having politicians from multiple municipalities directly participating in local stakeholder group dialogue improved the progress made on targeted water sustainability actions, since, we often find that having political buy-in can determine whether targeted actions succeed or fail.
Lessons learned about the process of use-inspired research
When I started the fellowship year, I planned to get into the field with stakeholders to observe different aspects of local geography, hydrogeology, and socioeconomic dynamics of Arizona’s principal karst region. Very early in the process, I recognized that dealing with above normal change and major uncertainties would be key variables I would grapple with. Now, as I reflect on 2021, my experience has certainly reinforced the value of doing use-inspired research; especially through the various lessons I learned. Among them is that building relationships with stakeholders to facilitate useable research takes time and compromise but can be most fulfilling. Plus, it improves the quality of research. For instance, while local stakeholders agreed to the research methodology during the design phase, by the start of the fellowship year, they prioritized a different design due to changes in their immediate needs and activities. Therefore, as a researcher, maintaining a degree of flexibility to ensure a win-win for all parties was a key point of learning during the past year.
Not long ago, I was a stakeholder working to develop or implement water regulations and plan actions to address sustainable management and use of karst groundwater resources in Jamaica. Then, I was often frustrated by the lack of robust data and information to support the work I was doing. My experience with research not fitting the needs on the ground was part of my motivation to pursue a doctoral degree. So, one key point of understanding for any researcher seeking to do use-inspired research is that initial plans may change quickly. Stakeholder priorities and timelines may sometimes diverge from academic research timelines and priorities. It is important for researchers to remain flexible, while working within the constraints of academic targets to ensure all parties benefit. Early in my fellowship journey, in order to respond to the change in stakeholders’ priorities, I adjusted my contribution to stakeholders’ processes from being academic research objective-driven to being driven by use-inspired objectives. I developed separate academic targets and timelines from that of stakeholders’ objectives and timelines. I worked on both simultaneously to ensure stakeholders got something from the collaboration while I worked towards longer-term academic objectives. This benefited my research by putting me in contact with individual stakeholders and provided opportunities for one-on-one communication. As a result, I got a better appreciation of the priorities and issues of individual, karst groundwater stakeholders. The collaboration also provided data that will shorten my research timeline and efforts to create similar datasets.
Despite the challenges of doing research in a pandemic, the CLIMAS fellowship was successful and rewarding for me as a researcher who was new to arid/semi-arid regions. It facilitated a dedicated space, and tools to focus attention on developing the skills necessary to navigate use-inspired research. Recognizably, it is easy to be in an academic silo, focused on achieving scientific rigor in your research and scholarship, without paying attention to who will use your research outputs; or how it will be used. So, the fellowship engagement provided a place to consider research that is relevant and useable versus only being an academic exercise. It has kept me accountable to myself for ensuring I consider stakeholders’ needs for science and information as I navigate meeting my academic targets.
Next steps in my use-inspired research journey
Although 2021 manifested in unexpected ways, I was grounded in my desire to conduct relevant research that responds to stakeholder needs. Ultimately, collaborating with stakeholders in the Coconino Plateau region to conduct use-inspired research, has provided knowledge and information to inform the design of my dissertation research. My dissertation will target modeling and assessing the vulnerability and contamination risks of groundwater stored in karst and alluvial aquifers to pollution and climate change. I will seek to advance understanding of differences in the dynamics of contamination risks and aquifer vulnerability in these two different aquifer systems, how climate variability and change will impact them, and how we can adapt to ensure the sustainability of groundwater resources. Based on the knowledge I gained of this arid karst region, I will now work to adapt my dissertation research design to consider the comparison of arid karst and alluvial systems in Arizona. This includes continuing to work on developing the geodatabase; which when complete will be shared with the stakeholders for their own use.
- Active Management Areas are designated under the Groundwater Management Act.
- Physical water scarcity occurs where water demand exceeds supply.
- Socioeconomic water scarcity occurs when there is an insufficient investment, skills or political will to increase access to the resource.
- Groundwater occurring in a saturated zone that is separated from the main underlying body of groundwater by unsaturated rock. It may be temporary or permanent depending on the amount and duration of recharge.