As the global climate warms and the world’s population grows, there will be greater pressure on water-abundant regions to maintain the sustainability of their fresh water resources and the viability of agricultural production. In the State of Michigan groundwater is a particularly important resource, as it provides drinking water for millions and irrigates much of the state’s cropland. In an effort to evaluate its long-term sustainability, I modeled the potential impacts of climate change on the water table of Kalamazoo County, MI. To do this I employed the Soil and Water Assessment Tool (SWAT) and a dataset of 31 future climate projections to produce multiple estimates of groundwater recharge to the year 2100. I then used these outputs from SWAT as inputs into an existing MODFLOW groundwater model of Kalamazoo County developed by the United States Geological Survey. I was then able to simulate changes in the county’s water table through the rest of the century, and under various potential future climates. Overall, the majority of climate scenarios projected an increase in water table elevation through the end of century, partly due to increases in precipitation, but also because of decreased evapotranspiration resulting from improvements in plant water use efficiency under elevated levels of CO2.I also explored the social context of these hydrologic simulations by measuring the awareness of groundwater sustainability threats, willingness to adopt conservation practices, and constraints to behavior change among large quantity water users in Michigan. These metrics are collectively referred to as social indicators, and have typically been used to describe surface water quality from a social perspective. For this project, I used them to describe groundwater sustainability. I administered an online social indicators survey as part of the State of Michigan’s annual online water use reporting for large quantity water users (> 378,541 liters per day). Overall, respondents exhibited high levels of awareness, were generally willing to adopt conservation, and identified cost as the principle constraint of behavior change. There were differences in the metrics for agricultural and non-agricultural respondents, but a relatively small sample size limited the analysis of additional demographic groups, including income, education level, gender, and geographic region.
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