{ Mapping & Analysis of Wastewater Spills in the Barton Springs and Southern Segments of the Edwards Aquifer Project manager: Katie Tritsch Asst. PM/Webdeveloper: Eric Schroeder GIS Analyst: Katie Steele GIS Analyst: Kevin Taylor Presented for: Greater Edwards Aquifer Alliance (GEAA)

{ BackgroundScope Literature Review DataMethodologyResultsConclusion Overview

{ Edwards Aquifer as an important resource Wastewater spill pollution from centralized sewage systems Increasing public awareness Increasing strength of regulations Background

Scope  Hays, Travis, Williamson Counties  RZ & CZ  TCEQ spill records, 500 gallons or more 

Literature Review  Wastewater spills in TCEQ Region 13  Predominately data collection  Limited analysis of spatial or temporal correlation – context  Successful press conference

Data collected Wastewater spill records TCEQ Roads TSDC Streams TWDB County boundaries CAPCOG City limits CAPCOG Census Tracts CAPCOG Edwards Aquifer zones TCEQ & TWDB

 TCEQ raw data put into separate columns  640 spill records processed, only 534 mapped Data Processing Table 1. Data received and data mapped County Spill records received Spill records mapped Data loss (%) Hays Travis Williamson

Methodology 1.Geocoding – Location and volume of spill 2.Interactive mapping w/ Manifold 3.Qualitative analysis – Why are these spill happening?  Original hypothesis of MUDs and GCDs refuted  Causes of spills  ‘Vulnerability’ of populations (Pop density + Spill density)

{ Maps & stats Results

TAKE AWAY…  534 spills mapped  Over 12 million gallons of wastewater spilled in 5 years  A little over 17% were in RZ

Manifold

Conclusion  Significant data loss due to lack of spatial information  Tighter regulation necessary?  Spills cannot be tied to outlying MUDs, but rather developing cities  Most spills in Austin, infrastructure repair may be necessary  Main cause of wastewater spills is line blockage, 2 nd is damaged pipes  Preventative methods  Lack of temporal pattern; frequency of spills throughout each year don’t significantly increase/decrease  Combined, 31% of spills occurred in both RZ & CZ (166 total)  Hope to aid in GEAA’s mission of improving aquifer health and expand public awareness with the addition of our data to GeoTex and future projects

Questions?