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Public Water System Violations: A case study in Alabama. 1 PhD Candidate, Dept. of Civil, Construction, and Environmental Engineering, University of Alabama, P.O. Box 870205, Tuscaloosa, AL 35487; e-mail: ltalebi@crimson.ua.edu
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Public Water System Violations: A case study in Alabama 1PhD Candidate, Dept. of Civil, Construction, and Environmental Engineering, University of Alabama, P.O. Box 870205, Tuscaloosa, AL 35487; e-mail: ltalebi@crimson.ua.edu 2Assistant Professor, London School of Hygiene and Tropical Medicine; e-mail: joebrown@bama.ua.edu 3Professor, Environmental and Water Resources Engineering, Department of Civil, Construction, and Environmental Engineering, University of Alabama, P.O. Box 870205, Tuscaloosa, AL 35487; e-mail:paulinej@eng.ua.edu Leila Talebi1, Joe Brown2, Pauline Johnson3
Introduction • Water distribution infrastructure plays a critical role in supporting public health by providing access to safe drinking water • One indicator of infrastructure function and therefore water safety might be reported health-based violations. • “Water Infrastructure Sustainability and Health in Alabama’s Black Belt” (EPA STAR Project)
Methodology The relation of reported violations with the size of PWS The relation of reported violations with Per Capita Income The relation of reported violations with Majority-Minority regions
What is a Public Water System? • Public Water System : “A system for the provision to the public of water for human consumption through pipes or other constructed conveyances, if such system has at least fifteen (15) service connections or regularly serves an average of twenty-five (25) individuals at least 60 days out of the year.”
Background • 530 Public Water systems • Serve a population of about 5.6 million • 67 Counties • 38 Very Small (<500) • 207 Small (501-3,300) • 178 Medium (3,301-10,000 ) • 107 Large (10,001 – 100,000) • about 57% of PWS’s in Alabama utilize groundwater as a source of water • about 70% of Alabama’s population are served by surface water. PWS’s Size Water Source Data Analysis
Map Alabama Median household income =$44,714
Total number of violations for HAA5, TTHM and Coliform Alabama Median household income =$44,714 Note: x-axis is sorted by the rank of income (census 2010)
Small systems have the most reported violations for TTHM, HAA5and also Coliform
Summary Table of Violations > 8x 197x 1Total violation/Population served*100,000
Majority- Minority Counties in Alabama • Bullock County (73.1% Af-Am) • Dallas County (63.3%) • Greene County (80.3%) • Hale County (59.0%) • Lowndes County (73.4%) • Macon County (84.6%) • Marengo County (51.7%) • Perry County (68.4%) • Sumter County (73.2%) • Wilcox County (71.9%)
Violations in Majority-Minority Counties 600% 180% 162% 139% 1Total violation/Population served*100,000
Coliform Violations TTHM Violations
HAA5 Violations Total Violations
Statistics Analysis Null Hypothesis: System Size Mean violation is the same for 4 different groups including very small, small, medium and large systems which means having same chance of violations for all system sizes Per Capita Income Mean violation is the same for 3 different groups including Top third per capita income, Middle third per capita income, and Lower third per capita income. • If the P-value in ANOVA test is <0.05 we will reject the null hypothesis • The ANOVA test has been done for TTHM, HAA5 and Coliformindividually
Questions • Are small systems more likely to experience health-related violations? • Are poorer (per-capita) systems more likely to experience health-related violations? • Are majority-minority systems more likely to experience health related violations? Systems
Are small systems more likely to experience health-related violations? ANOVA Result Total Coliform Modified Hypothesis: Mean violation is the same for 2 different groups of very small plus small, and medium plus large systems
Are small systems more likely to experience health-related violations? ANOVA Results HAA5 TTHM P-value > 0.05
Are small systems more likely to experience health-related violations? Total Violations = Coliform+TTHM+HAA5
Are poorer (per-capita) systems more likely to experience health-related violations? Top third per capita income = 39,290 - 71,785 Middle third per capita income = 32,888 – 39,290 Lower third per capita income = 23,090 – 32,888 173% 125%
Are majority-minority systems more likely to experience health related violations? Bullock County (73.1% Af-Am) Dallas County (63.3%) Greene County (80.3%) Hale County (59.0%) Lowndes County (73.4%) Macon County (84.6%) Marengo County (51.7%) Perry County (68.4%) Sumter County (73.2%) Wilcox County (71.9%)
Conclusion • Very small and small water systems in the Alabama are more likely to report exceeding values for Total Coliform, TTHM and HAA5. • The poorer area in the Alabama are more likely to have Total Coliform, TTHM and HAA5 violations. • Reported SDW violations for the Majority-Minority areas in Alabama is higher. • If there was an equal monitoring conditions for different size of PWS, it would be possible to see even more reported violations for smaller systems.