The Examiners Are:

Dr. Steven P. French (Chair)

Dr. Bruce Stiftel

Dr.  William Drummond

Dr. Marilyn Brown

Dr. Richard Klosterman

Faculty and students are invited to attend this examination.

Abstract:

The increase of population, urbanization and sprawl, and decay of the existing conventional infrastructure continuously raise water issues in urban areas in the US, and therefore, sustainable water use management is an imperative task for local and regional planning authorities.  Although the level of water use is closely tied to land use types and physical characteristic of built environment, not many studies have examined the importance of the integration of land-use and future growth policies to sustainable water use framework.

This dissertation study discusses the sustainable water use framework including water use determinants and proposes a GIS modeling application called 'Sustainable water use scenario-based decision support systems’ (SWSPSS) that allows planners to test a series of water conservation and sustainable growth policies.  The major research questions in this study are:   (1) What are the relationship between urban water use and the factors pertain to urban form and the development configuration, (2) What are the impacts of alternative urban growth and water conservation scenarios on urban water use and how can planners easily demonstrate them using planning decision support systems (PSS)?

This study is composed of three research tasks to discuss sustainable water use and the development of the GIS application:  (1) an empirical regression analysis to examine the relationship between key water measures (county per capita water use rate and annual volume of residential household water use) and the factors of urban form or those of urban development configuration, (2) development of sustainable water use scenarios based on local water use profiles and rainwater harvesting (RWH) potential and (3) development of GIS application using Python scripting and ModelBuilder in ArcGIS software environment to forecast future water demand.  13 counties in Atlanta metro region are selected as a case study area to test the SWSPSS and examine analysis results.

The dissertation finds that a series of urban form variables associated with sprawl and low-density development configuration (population density, percent of single family housing, lot size) are correlated to water use rates at county level and at household level. The results support the proposition that the compact growth policy promoting high density and mixture of residential types would reduce per capita urban water use rate in the long-run.  The results from the SWSPSS application run showed the sustainable water use strategies provide a significant return within Atlanta context.  It is estimated that the urban water demand in 13 counties in the metro region would substantially be changed from 585.8 million gallons per day in 2010 to 997.5 million gallons per day by 2040 due to increase of population and employment. However, with sustainable water use scenarios, the total water demand could be reduced to 843 million gallons per day by 2040. When the RWH conservation combined, additional savings of 71.4 million gallons per day in 2040 can be achieved.  The SWSPSS also provides spatial layers of land uses and water use patterns in future so that planners can easily identify the range of water consumption in space and higher priority areas for additional infrastructure provision in the future.

In sum, this research offers the methodological framework to integrate water conservation strategies with growth scenarios for sustainable urban water management. To envision sustainable urban communities, planners should have keen understanding of spatial variability of urban settlement patterns and should be able to quantify such impacts on water demand.   This study will enrich the discussion in two folds that why conservation and proper growth policies are critical in local and regional water demand plan makings and how the efforts to develop GIS applications using scripting languages and geoprocessing models benefit planners.