Three essays on water scarcity adaptation
Authors:   , Pongspikul Tayatorn Kungsavanich 
Published: November 2024

[EMBARGOED UNTIL 08/01/2025] This three-essay dissertation examines two types of technologies used for adaptation to water scarcity: pressure irrigation systems and desalination. In addition, this dissertation also investigates the applications of these technologies in the agricultural, municipal, and tourism sectors. Since the agricultural sector is the main user of water in the U.S. and the world, it is critical to improve irrigation water efficiency. Desalination, the process of removing salt from water, is an option for providing fresh water to the municipal and tourism sectors, given the rising demand for water. The first essay of this dissertation investigates the factors affecting the adoption of pressure irrigation systems versus gravity irrigation systems by comparing cotton irrigators in the southeastern region to those in the southwestern region of the U.S. Pressure irrigation systems have better water use efficiency than gravity systems. The southeast and southwest cotton growing regions have different climates, water institutions, and varieties. A probit model of adoption decisions of cotton producers used data from the 2015 USDA Agricultural Resource Management Survey. In the Southeast, producing rice is negatively associated with adoption of pressure irrigation systems while use of irrigation management services is positively associated. For both regions, a higher percentage of owned land is associated with increased adoption. In the Southwest, age and using surface water are negatively associated with adoption, while cotton specialization and higher water cost are positively associated. The second essay analyzes the factors affecting the adoption intensity of municipal membrane desalination plants by counties in California, Florida, and Texas. Using desalination data from the Global Water Intelligence's DesalData, a negative binomial model was used to analyze adoption intensity. The number of desalination plants in the three states has steadily increased since 1970. Florida has the highest number of desalination plants. The regression results show that population, per capita personal income, average temperature, access to brackish groundwater, and access to both brackish groundwater and coastal shoreline are positively associated with the adoption intensity of desalination. However, average precipitation is negatively associated with the number of desalination plants adopted. For the state dummy variables, compared to counties in Florida, counties in California and Texas would be expected to adopt fewer desalination plants on average. The last essay analyzes the characteristics and trends of desalination plants for tourist facilities worldwide and examines the effect of the desalination facility characteristics on the capital cost of desalination. The DesalData show that the Middle East and North Africa region is the main region of desalination adoption for tourist facilities, followed by Western Europe, then Latin America and the Caribbean. Furthermore, the main desalination technology is reverse osmosis, and seawater is the primary feedwater source. The multiple regression results show that the determinants of the capital cost per m3/day of desalinated water include the desalination technology used, the age of the desalination facility, feedwater salinity, and the state of the economy. Lastly, the data from the second and third essay suggest that desalination is maturing since desalination has been growing at a slower pace in the recent years.