Relationship Between Lake Whatcom Algae Density, Water Quality and Filtration Rate at the Bellingham Water Treatment Plant, WA
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Western Washington University Western CEDAR WWU Graduate School Collection WWU Graduate and Undergraduate Scholarship 2013 Relationship between Lake Whatcom algae density, water quality and filtration rate at the Bellingham Water Treatment Plant, WA Bowei He Western Washington University Follow this and additional works at: https://cedar.wwu.edu/wwuet Part of the Environmental Sciences Commons Recommended Citation He, Bowei, "Relationship between Lake Whatcom algae density, water quality and filtration rate at the Bellingham Water Treatment Plant, WA" (2013). WWU Graduate School Collection. 319. https://cedar.wwu.edu/wwuet/319 This Masters Thesis is brought to you for free and open access by the WWU Graduate and Undergraduate Scholarship at Western CEDAR. It has been accepted for inclusion in WWU Graduate School Collection by an authorized administrator of Western CEDAR. For more information, please contact [email protected]. Relationship between Lake Whatcom Algae Density, Water Quality and Filtration Rate at the Bellingham Water Treatment Plant, WA By Bowei He Accepted in Partial Completion of the requirements for the Degree Master of Science Kathleen L. Kitto, Dean of the Graduate School ADVISORY COMMITTEE Chair, Dr. Robin A. Matthews Dr. Leo Bodensteiner Dr. Wayne Landis i MASTER’S THESIS In presenting this thesis in partial fulfillment of the requirements for a master’s degree at Western Washington University, I grant to Western Washington University the non- exclusive royalty-free right to archive, reproduce, distribute, and display the thesis in any and all forms, including electronic format, via any digital library mechanisms maintained by WWU. I represent and warrant this is my original work, and does not infringe or violate any rights of others. I warrant that I have obtained written permissions from the owner of any third party copyrighted material included in these files. I acknowledge that I retain ownership rights to the copyright of this work, including but not limited to the right to use all or part of this work in future works, such as articles or books. Library users are granted permission for individual, research and non-commercial reproduction of this work for educational purposes only. Any further digital posting of this document requires specific permission from the author. Any copying or publication of this thesis for commercial purposes, or for financial gain, is not allowed without my written permission. Bowei He December 3, 2013 ii Relationship between Lake Whatcom Algae Density, Water Quality and Filtration Rate at the Bellingham Water Treatment Plant, WA A Thesis Presented to The Faculty of Western Washington University In Partial Fulfillment Of the Requirements for the Degree Master of Science By Bowei He November 2013 iii ABSTRACT During the summer of 2009, the Bellingham drinking water treatment plant experienced severe reductions in filtration rates, resulting in mandatory water restrictions. Since then, summer water filtration rates continued to approach critical levels. In 2011, I conducted a study to investigate the phytoplankton and ambient water quality patterns in Lake Whatcom source water to see if any parameters could be used to predict low water filtration rates. In addition, I evaluated water quality and phytoplankton cell densities at different depths at the intake located in Lake Whatcom to see if drawing source water from different depths could help reduce water filtration problems. Water quality and algae samples were collected at the treatment plant screen house and at the intake in Lake Whatcom between June 15 and November 30. During the study period, 62 algal taxa were collected at the screen house. Aphanocapsa/Aphanothece (Cyanobacteria) dominated the algal cell density and Cyclotella and Stephanodiscus (Bacilliariophyta) dominated the algal biovolume, but no single taxon was a unique predictor of low water filtration rates. Among the water quality parameters, nitrate/nitrite had the strongest correlation with filtration rates. Hierarchical cluster analysis was conducted using the first four principal components generated using water quality and algal taxa cell densities, omitting filtration rates and redundant variables. Hierarchical clustering resulted in two distinct clusters that were associated with low and high filtration rates. The samples from the low filtration rate group were characterized by higher water temperatures, conductivities, and alkalinity levels; lower turbidities, nitrate/nitrite and ammonium concentrations; higher cell densities of Aphanocapsa/Aphanothece, Stephanodiscus, Fragilaria, Synedra, Thalassiosira, Naviculoid group, Scenedesmus, Chlamydomonas, Elakatothrix, Cryptomonas, Gymnodinium and Peridinium. Cell morphological characteristics, including mucilage production, elongated cell and presence of iv fiber threads, were shared by many of the dominant algae in the low filtration rate group and may contribute to the slow filtration. The water quality and phytoplankton community were similar between the screen house and intake sites. In addition, the water column at the intake site was usually unstratified and well-mixed, creating high degree of uniformity in the water quality and phytoplankton data at all depths. Varying the intake depth, which is currently at 10 meters in Basin 2 of Lake Whatcom, is not likely to reduce the effects of problematic algae on water filtration rates. v ACKNOWLEDGEMENTS I wish to thank various people for their contribution to this project. I would like to express my very great appreciation to my advisor Dr. Robin Matthews for the invaluable suggestions and guidance from beginning of this research project and for great patience and encouragement. I also want to give sincere thanks to my committee members, Dr. Leo Bodensteiner and Dr. Wayne Landis for constructive suggestions and comments. I would like to thank the Institute for Watershed studies for providing sampling equipment and sharing the lab resources. I am grateful to IWS staff, Joan Vandersypen and Michael Hilles, and interns for all the assistance of sample collection and laboratory analysis. I also want to express great appreciation to Bill Evans and Peg Wending at Bellingham Public Works Department for providing data as well as accessibility to the Bellingham drinking water treatment plant. I also want to thank my family and all my friends for being supportive and encouraging throughout these years. vi TABLE OF CONTENTS ABSTRACT ............................................................................................................................ iv ACKNOWLEDGEMENTS .................................................................................................. vi INTRODUCTION................................................................................................................... 1 Background ....................................................................................................................... 1 Objectives........................................................................................................................... 5 METHODS .............................................................................................................................. 6 Sample Collection .............................................................................................................. 6 Screen house site sampling ............................................................................................. 6 Lake Whatcom intake site sampling ............................................................................... 7 Sample Analysis ................................................................................................................ 8 Water chemistry .............................................................................................................. 8 Algae counts and biovolume estimation ......................................................................... 8 Quality Control ............................................................................................................... 10 Additional Data Available for Thesis ............................................................................ 11 Statistical Analyses.......................................................................................................... 11 Multivariate analysis ...................................................................................................... 12 RESULTS AND DISCUSSION ........................................................................................... 13 Water Filtration Rates in 2011 ...................................................................................... 13 Water Quality and Phytoplankton at the Screen House ............................................. 14 Water quality ................................................................................................................. 14 Phytoplankton ................................................................................................................ 15 Correlation between water quality variables ................................................................. 17 Correlation between filtration rates, water quality, and phytoplankton ........................ 19 Multivariate Analysis...................................................................................................... 20 Water Quality and Phytoplankton at the Lake Whatcom Intake .............................. 25 SUMMARY AND CONCLUSIONS