Conference Agenda

The agricultural sector is the primary water consumer in the US. Groundwater is one of its main sources, with 65% of irrigated farmland relying on groundwater for their water supply. Groundwater use presents a common pool problem: if a farmer pumps groundwater, she decreases the aquifer's water table and thus increases the cost of pumping for farmers in the same aquifer. Studying such a problem is challenging due to a lack of markets and data on groundwater use. In this paper, I leverage detailed farmer-level data on (ground)water use, crop choices, and crop yields to study the equilibrium implications of the current groundwater costs. I focus on the Ogallala Aquifer in Nebraska. In order to estimate the effect of water costs on water use and crop choices, I combine a crop-growth model with an economic model. I use the crop-growth model to recover the precise relation between water use and crop yields. I use the economic model to estimate the marginal cost of water for farmers. I then quantify how farmers respond to water costs by switching which crop they plant or changing the water use per planted crop. I find that farmers are inelastic to water costs: a 10% increase in the water cost would decrease water use by 3%. Moreover, I find that farmers adapt to higher water costs by both reducing the water use per planted crop and fallowing the land. Lastly, I utilize my estimates to compute the optimal and sustainable tax on groundwater use.

While climate change is projected to deeply modify melting processes of solid water, the links between snow packs and glaciers seasonal melt and downstream economic activities is still unclear. In an econometric analysis of melt water shocks and overall economic activity at sub-national levels, I deepen the understanding of whether and through which channel hydrological conditions affect economic development. I construct a new data set of monthly melt water shocks based on snow cover, glaciers data and temperature and combine them with nighttime light intensity at the grid cell level over the entire region of Himalayan-fed watersheds. The data set covers all months from 2000 to 2013. I estimate the month-specific annual change in economic development in a watershed as a function of current and past melt water shocks, accounting for all upstream watershed’s contributions. This paper provides further evidence that upstream hydrological conditions have causal effects on downstream economic development. The key findings are that (i) economic development does not benefit from excessive meltwater volumes, (ii) meltwater shortages have causal negative impacts on downstream economic activities, especially in the early melt season and (iii) agriculture is the main channel through which the impacts propagate through the economy.

The majority of U.S. animal farming takes place in industrial Animal Feeding Operations (AFOs), where large quantities of manure are produced, stored, then typically spread onto fields. The concentration of animal waste is thought to threaten environmental and public health, as airborne and waterborne transmission puts communities at risk of environmental exposure to its contaminants. Water pollution from swine operations is of particular concern yet there are no robust causal estimates of this externality to date.

I gather panel data of all permitted AFOs in the two main hog producing states — Iowa (2002-2017) and North Carolina (1997-2020) — and estimate the effects of animal production on downstream surface water quality readings.

My analysis espouses the spatial structure of the underlying process by constructing station-specific drainage areas, and I use two identification strategies appropriate for the states' regulatory settings and data resolution: the first leverages the spatio-temporal variation in animal production in Iowa, the second the randomness of intense precipitation events on North Carolina farms.

I find deleterious effects across water quality indicators and across types of operations, including from facilities below the size threshold at which the industry is currently regulated. A daily rainfall extreme at an AFO increases downstream levels of fecal coliforms by 3.5\%, and nutrients by 0.5-0.7\%, relative to mean sample levels, while an additional swine operation in the average station drainage area increases nutrient concentrations by 3.8-10.7\% and decreases dissolved oxygen by 1.1\%, relative to sample mean levels. These effects are higher than previous findings focused on large dairies, and are higher for swine AFOs relative to all AFOs.

Although there are significant concerns about water pollution from hydraulic fracturing, the repercussions for drinking water treatment have not been explored. We examine the effects of unconventional oil and gas (UOG) production on Safe Drinking Water Act (SDWA) compliance in the Marcellus shale region from 2000 to 2022. The results from difference-in-difference (DiD) analysis reveal a significant and positive association between UOG exposure and SDWA violations, especially in the early years of the fracking boom. Violations increase by 0.41–0.74 per year per CWS after exposure to UOG production. Health-related violations show no significant impact, indicating that Community Water System operators prioritized health standards compliance relative to monitoring, reporting and other requirements. The results are confirmed using matched DiD regressions.