The complicated relationship between human activities and water quality/quantity has interested many researchers. My primary research interest lies in environmental economics and water resource policy. This dissertation studies water quality and water quantity in the United States, especially groundwater. In particular, the first chapter, “The Conservation Reserve Program and Nutrient Pollution in Groundwater”, studies how the Conservation Reserve Program (CRP) affects groundwater quality in the United States. The second chapter of my dissertation, “Reliable Drinking Water Supply and Cities’ Resilience to Drought” (joint with Dr. David Keiser, Dr. Gabriel Lade, and Dr. Ivan Rudik), studies how differences in drinking water supply sources affect how cities adapt to and respond to extreme weather events. The third chapter of my dissertation, “The Effectiveness of Phosphorus Lawn Fertilizer Bans” (joint with Dr. David Keiser), studies the effectiveness of incomplete phosphorus lawn fertilizer bans in Florida by utilizing a restricted consumer scanner data and fixed effects model.