Flood-Proofing Communities with Land Use Planning and Design
Abstract
This dissertation evaluated how spatial patterns of pervious land cover moderate flood impacts in urban areas during an extreme rainfall event. First, it presented criteria to characterize hydrologic functions of natural landscape features through spatial metrics of size, proportion, abundance, and shape; second, it described improvements to measurements of flood risk and other context variables; third, it evaluated flood risk and severity of damage in urban neighborhoods using insurance and parcel data; and forth, it identified different design strategies that urban developers, communities and city planners could apply to mitigate flood damages or enhance community flood resilience.
Innovative methodological approaches to sampling and variable measurement were applied to analyze neighborhood-level damages of single-family residential properties covered by the National Flood Insurance Program in Harris County, Texas, at the time of Tropical Storm Allison (June 2001). A total of 68,351 insured properties comprised a sample of 532 neighborhoods in the study area. Risk, mitigation, socioeconomic, hazard, and environmental context variables were included in statistical regression models as controls.
Results indicated that the hydrological functions of natural landscapes persist in urban areas. Wetlands, large pervious areas, cultivated agricultural parcels, and greenways and large urban parks of grass open space have important and statistically significant contributions to flood damage mitigation. Increasing some of these by 10% at neighborhood levels could have resulted in damage-cost reductions totaling over $100 million (USD 2001). Isolated patches of grass open space were found to increase flood risk, an indication that not all types of pervious areas can enhance flood resilience. Forested landscapes, however, were statistically insignificant.
Floods are frequent natural disasters that are often costly. While the potential hydrological benefits of pervious surfaces are generally understood, few studies have sought to evaluate the effects that the type, form, and structure of pervious areas may have on regulating the performance of cities with respect to floods. This dissertation’s results can be used to assess the relative importance of pervious areas for flood mitigation and to qualify and estimate the potential economic consequences of some land-use decisions.
Subject
flood lossflood risk
resilience
disasters
planning
neighborhoods
mitigation
wetlands
open space
land use
land cover
landscape ecology
spatial analysis
urban design
GIS
Tropical Storm Alison
NFIP
Houston
Harris County
Texas
Citation
Lorente, Paula (2016). Flood-Proofing Communities with Land Use Planning and Design. Doctoral dissertation, Texas A & M University. Available electronically from https : / /hdl .handle .net /1969 .1 /157089.