| dc.description.abstract | According to the 2004 303(d) List, 192 segments are impaired by bacteria in the State of
Texas. Impairment of streams due to bacteria is of major concern in several urban
watersheds in Texas. In order to assess, monitor and manage water quality, it is
necessary to characterize the sources of pathogens within the watershed. The objective
of this study was to develop a spatially explicit method that allocates E.coli loads in the
Plum Creek watershed in East Central Texas. A section of Plum Creek is classified as
impaired due to bacteria. The watershed contains primarily agricultural activity and is in
the midst of an urban housing boom.
Based on a stakeholder input, possible sources E. coli were first identified in the
different regions of the watershed. Locations of contributing non-point and point sources
in the watershed were defined using Geographic Information Systems (GIS). By
distributing livestock, wildlife, wastewater treatment plants, septic systems, and pet
sources, the bacterial load in the watershed was spatially characterized. Contributions
from each source were then quantified by applying source specific bacterial production
rates. The rank of each contributing source was then assessed for the entire watershed.
Cluster and discriminant analysis was then used to identify similar regions within the
watershed for assistance in selection of appropriate best management practices. The
results of the cluster analysis and the spatially explicit method were compared to identify
regions that require further refinement of the SELECT method and data inputs. | en |
