Spatiotemporal Analysis of Escherichia Coli Along Metro-Atlanta Surface Waters
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Georgia State University ScholarWorks @ Georgia State University Public Health Theses School of Public Health 8-8-2017 Spatiotemporal Analysis of Escherichia coli along metro-Atlanta Surface Waters Diana Orquiola Follow this and additional works at: https://scholarworks.gsu.edu/iph_theses Recommended Citation Orquiola, Diana, "Spatiotemporal Analysis of Escherichia coli along metro-Atlanta Surface Waters." Thesis, Georgia State University, 2017. https://scholarworks.gsu.edu/iph_theses/552 This Thesis is brought to you for free and open access by the School of Public Health at ScholarWorks @ Georgia State University. It has been accepted for inclusion in Public Health Theses by an authorized administrator of ScholarWorks @ Georgia State University. For more information, please contact [email protected]. Spatiotemporal Analysis of Escherichia coli along metro-Atlanta Surface Waters by DIANA MARIE ORQUIOLA B.S., UNIVERSITY OF GEORGIA A Thesis Submitted to the Graduate Faculty of Georgia State University in Partial Fulfillment of the Requirements for the Degree MASTER OF PUBLIC HEALTH ATLANTA, GEORGIA 30303 ABSTRACT Spatiotemporal Analysis of Escherichia coli along metro-Atlanta Surface Waters DIANA MARIE ORQUIOLA (Under the direction of Dr. Lisa Casanova) Introduction: The Chattahoochee River and its lakes and tributaries are essential resources for metro-Atlanta; however, urbanization and other human impacts near these resources affects the quality of water. The objectives of this study are to describe the spatial and temporal patterns of Escherichia coli (E. coli), and examine the relationship between rainfall and E. coli levels in metro-Atlanta surface waters, including the Chattahoochee River and its lakes and tributaries. Methods: The water quality data used for the study was originally collected and analyzed by the Chattahoochee Riverkeeper (CRK) Neighborhood Water Watch (NWW) program. For this analysis, sites with a total of 50 samples or more were subjected to descriptive analysis. Results: Twenty-seven of the 36 sites had a mean E. coli concentration exceeding the US EPA’s recreational water quality criteria of 2.37 log Most Probable Number per 100 milliliters. Sites with the highest and lowest mean E. coli levels were located, on average, 2.77 and 20.22 miles from downtown Atlanta, respectively. Spikes in E. coli levels occurred 99 counts of 699 sampling events in the winter, 168/827 spring, 141/877 summer, and 170/950 fall. Seven of the 36 sites were analyzed to examine the relationship between 48-hour rainfall and E. coli levels. Four sites indicated that there was a significant positive correlation between the two variables. (r=0.52, p<.0001; r=0.67, p<.0001; r=0.39, p<.0001; r=0.38, p<.0001) Discussion: The water quality in waterways closer to downtown may be attributable to combined sewer overflows and the urbanization and land use associated with the city. Overall, there was temporal variation in E. coli concentrations, however there was no distinct seasonal pattern. The relationship between 48-hour rainfall and E. coli levels of four of the seven sites analyzed was consistent with other studies. ii APPROVAL PAGE Spatiotemporal Analysis of Escherichia coli along metro-Atlanta Surface Waters by DIANA MARIE ORQUIOLA Approved: Dr. Lisa Casanova Committee Chair Dr. Christine Stauber Committee Member Friday, July 28, 2017 Date iii ACKNOWLEDGMENTS First and foremost, I would like to thank my thesis chair, Dr. Lisa Casanova, for providing me the opportunity to work on this project. I would also like to thank my thesis committee member, Dr. Christine Stauber, for sharing her knowledge and support. I am truly grateful for the patience and guidance that both Dr. Casanova and Dr. Stauber have shown me through my thesis process and time at Georgia State. I would also like to thank the Chattahoochee Riverkeeper, its interns, and volunteers for their continuous efforts to protect and preserve the Chattahoochee River and its lakes and tributaries. The work you do will never be overlooked. Lastly, I would like to thank my family, friends, and fellow classmates who have offered their advice or knowledge through this process. A special thank you goes out to my parents, Edgar and Connie Orquiola, for their constant love and support; I would not be where I am today without you both. iv AUTHOR’S STATEMENT In presenting this thesis as a partial fulfillment of the requirements for an advanced degree from Georgia State University, I agree that the Library of the University shall make it available for inspection and circulation in accordance with its regulations governing materials of this type. I agree that permission to quote from, to copy from, or to publish this thesis may be granted by the author or, in her absence, by the professor under whose direction it was written, or in her absence, by the Associate Dean, School of Public Health. Such quoting, copying, or publishing must be solely for scholarly purposes and will not involve potential financial gain. It is understood that any copying from or publication of this dissertation which involves potential financial gain will not be allowed without written permission of the author. _________________________ Author’s Signature v NOTICE TO BORROWERS PAGE All theses deposited in the Georgia State University Library must be used in accordance with the stipulations prescribed by the author in the preceding statement. The author of this thesis is: Diana Marie Orquiola 3620 Jardine Lane Cumming, GA 30041 The Chair of the committee for this thesis is: Dr. Lisa Casanova Division of Environmental Health School of Public Health Urban Life Room 445 Georgia State University School of Public Health P.O. Box 3995 Atlanta, Georgia 30302‐3995 Users of this thesis who not regularly enrolled as students at Georgia State University are required to attest acceptance of the preceding stipulation by signing below. Libraries borrowing this thesis for the use of their patrons are required to see that each user records here the information requested. TYPE OF USE NAME OF USER ADDRESS DATE (EXAMINATION ONLY OR COPY) vi TABLE OF CONTENTS ACKNOWLEDGMENTS.….…………………………………………………………………....iv LIST OF TABLES………………………………………………………………..………...…..viii LIST OF FIGURES.......………………………………………………………………......……...ix LIST OF MAPS………………………………………………………………………..………….x LIST OF ACRONYMS AND ABBREVIATIONS………………………...…………..……......xi I. INTRODUCTION……………………………………………………………………………....1 1.1 Background……………………………………………………………………………1 1.2 Study Objectives………………………………………………………………………7 II. LITERATURE REVIEW………………………………………...…………………………….8 2.1 Recreational water illnesses (RWIs)……………………………..……………………8 2.2 Escherichia coli (E. coli) …………………………………………………………..…8 2.3 E. coli and Spatial Variability…………………………………………………………9 2.4 E. coli and Temporal Variability……………………………………………………...9 2.5 E. coli and Rainfall…………………………………………………………………..10 2.6 Relevance of Study…………………………………………………………………..11 III. MATERIALS AND METHODS……………..…………………………………………..….13 3.1 Data Source…………………………………………………………………..……....13 3.2 Analysis of data……………………………………………………..………………..15 IV. RESULTS…………….……………………………………………………………...……....19 4.1 Descriptive Statistics…………………………………………………………………19 4.2 Spatial Patterns of E. coli…………………………………………………………….22 4.3 Temporal Patterns of E. coli…………………………………………………………25 4.4 Relationship between 48- hour Rainfall and E. coli levels…………...…………..….40 V. DISCUSSION….…………………………………………...………………………………...49 5.1 Neighborhood Water Watch (NWW)…………………………………………..……49 5.2 Spatial Patterns of E. coli…………………………………………...………………..49 5.3 Temporal Patterns of E. coli…………………………………………………………50 5.4 Relationship between 48-hour Rainfall and E. coli levels…………………...………51 5.5 Significance and Impact of the Study………………………………………………..51 5.6 Limitations and Recommendations………………………………………………….52 5.7 Conclusion…………………………………………………………………………...52 APPENDIX A: Additional NWW Tables..…………………………………………………...….54 APPENDIX B: SAS Descriptive Statistics…...…….………………………………………...….60 APPENDIX C: Additional Box Plots and Graph Results..…………………………………...….62 APPENDIX D: Sites with 20-49 Samples Box Plot…………………………………………....120 REFERENCES…...………………………………………………………………………...…..121 vii LIST OF TABLES TABLE 3.1.1: DILUTION VOLUMES TO TARGET E. COLI CONCENTRATIONS.....……14 TABLE 4.1.1: DESCRIPTIVE ANALYSIS FOR ALL SITES………………………..………..19 TABLE 4.2.1: SITES WITH THE LOWEST MEAN E. COLI……………………....…………24 TABLE 4.2.2: SITES WITH THE HIGHEST MEAN E. COLI…………………...…….…...…24 TABLE 4.3: NUMBER OF SPIKES AND SAMPLING EVENTS PER SEASON……......…...25 TABLE 4.3.1a: NUMBER OF SPIKES…CHATTAHOOCHEE RIVER AT FRANKLIN........26 TABLE 4.3.1b: MEDIAN & MEAN E. COLI…AT FRANKLIN……………………………....26 TABLE 4.3.2a: NUMBER OF SPIKES…CHATTAHOOCHEE RIVER AT MEDLOCK.........28 TABLE 4.3.2b: MEDIAN & MEAN E. COLI…AT MEDLOCK……………………...……….28 TABLE 4.3.3a: NUMBER OF SPIKES…CLEAR CREEK AT PIEDMONT……….…….…...30 TABLE 4.3.2b: MEDIAN & MEAN E. COLI…CLEAR CREEK AT PIEDMONT……..…….30 TABLE 4.3.4a: NUMBER OF SPIKES…DUCK POND EAST………………………………..32 TABLE 4.3.4b: MEDIAN & MEAN E. COLI…DUCK POND EAST…………………...…….32 TABLE 4.3.5a: NUMBER OF SPIKES…GREENSFERRY CSO……………………………...34 TABLE 4.3.5b: MEDIAN & MEAN E. COLI…GREENSFERRY CSO……………………….34 TABLE 4.3.6a: NUMBER OF SPIKES…NISKEY LAKE……………………………………..36 TABLE 4.3.6b: MEDIAN & MEAN E. COLI…NISKEY LAKE………...…………………….36 TABLE 4.3.7a: NUMBER OF SPIKES…TANYARD CREEK PED. BRIDGE…...…………..38 TABLE 4.3.7b: MEDIAN & MEAN E. COLI…TANYARD CREEK PED. BRIDGE...………38 TABLE 4.4.1: PEARSON CORRELATION- 48-HOUR RAINFALL & E. COLI…………..…40