A new study published in Water Resources Research examines the influence of development patterns on water use in North and South Carolina.

Effective water management planning depends on society’s ability to understand how water is being used. Scientists are increasingly recognizing that spatial patterns of urban development influence geographic differences in water demand. Therefore, assessing what factors related to urban development impact water use can help inform water planning efforts. While this relationship has been assessed at small scales, such as individual cities, it has not been modeled at a larger landscape or regional scale.

A team of scientists supported by the Southeast CASC and the USGS South Atlantic Water Science Center explored the drivers behind water use, including development patterns, using North and South Carolina as a study site. The research team was led by Georgina Sanchez, a 2015 Global Change Fellow with the Southeast CASC, and included Southeast CASC Research Ecologist Adam Terando.

The authors used USGS water use records from the USGS National Water-Use Science Project, which compiles water use information from local, State and Federal agencies on a five-year basis. Land cover data from the National Land Cover Dataset was used to identify developed areas. Lastly, the authors used socio-economic data (e.g., population, income, and education) and environmental data (e.g., temperature and precipitation) to check if these factors also affect water use. Only nationally available datasets were used, so that the analysis could be easily replicated in other regions of the country.

Results show that different development patterns have a strong effect on the way communities use water for domestic, industrial, and public supply needs. In fact, development patterns had a larger influence on variations in water use than the socio-economic and environmental variables, which are more commonly used to estimate water use. In the study area, urban spatial patterns that were simpler and more compactly developed had lower demand for water. 

Understanding the relationship between spatial patterns of urbanization and water use is a key step in helping guide more water efficient land developments. These findings can help local and state governments better understand the implications of their planning and development choices on future water demand, while also anticipating the sensitivity of future regional water demand to future urbanization.

This study opens a frontier for water resources researchers to develop models of water use and land change to explore alternative futures of urbanization and regional demands for scarce supplies of water.