Examination of Water Use and Social Vulnerability: A Comparison of Four Communities in Alachua County, Florida

Abstract

It is projected that about 30% of the world’s major cities will face severe water stress and urban drought from 2050 if climate change continues and has the anticipated effects (Florke et al, 2018; www.wrcwebsite.azurewebsites.net). Socio-economic drought, meaning water shortage in urban life, can have significant effects on a city’s inhabitants, including health and quality of life. Social and economic factors play an important role in planning and decision making of a society (Zhang et al, 2020). The analysis investigated the relationship between socio-economic factors and the use of potable water, its associated impact on aquifer recharge, and potentially identifying major factors influencing water demand and resource sustainability.

The Centers for Disease Control and Prevention’s Social Vulnerability Index (SVI) and other measures were used for evaluating socio-economic factors. However, since SVI showed weak relationship with water use in the county and the neighborhoods, other socio-economic measures were assessed. Past research had found a correlation between water use and population, GDP, per capita income, electricity usage and irrigated land areas (Alacoma et al., 2007, www.usf.uni-kassel.de/watclim). Therefore, socio economic measures such as population density, household size, per capita income, and poverty rate and irrigation (with and without) potable water were analyzed to evaluate the relationship between water use patterns and these factors across the county and in the communities. The western communities had newer development and less parcels compared to the eastern with much older construction, which impacted their water use. Oakmont with separate reclaimed irrigation meter had lesser usage on potable water. Tioga on the other hand irrigated with potable water.  

Yearly SVI on a census tract level for the specific years of the study and other socio-economic measures such as population, per capita income, poverty, and household size were used in the analysis.

The analysis was performed on four communities in Alachua County, Florida; two at the west and two at the east of the county. Socio-economic measures and physical features were evaluated for communities in the four locations to evaluate whether there is a relationship between water use patterns, spatial characteristics of development such as percent impervious and runoff, and measures of SVI. Spatial and basic statistics was used for this analysis. 

The western part of the county has had more intensive development in recent years compared to the eastern part of the county. The eastern communities have a high SVI and low potable water use per capita compared to the western communities. The number of households and population were the primary drivers of potable water use per census block. Percent impervious surface and runoff volume did not show any significant. relationship with a community’s SVI. At the parcel level, statistically significant differences were found between communities. For example, potable water use per parcel was lower in communities with high SVI. 

Keywords: water sustainability, urban water management, social vulnerability index, socio-economic factors, potable water use, aquifer recharge, reclaimed water use, runoff, imperviousness