NUTRIENT AND WATER QUALITY ANALYSIS OF A
LAKE ERIE HEADWATER TRIBUTARY
A Thesis
Presented to
The Graduate Faculty of The University of Akron
In Partial Fulfillment
of the Requirements for the Degree
Master of Science
MaryAnne Hejna
August 2020
NUTRIENT AND WATER QUALITY ANALYSIS OF A
LAKE ERIE HEADWATER TRIBUTARY
MaryAnne Hejna
Thesis
Approved: Accepted:
______Advisor Department Chair Dr. Teresa J. Cutright Dr. Wieslaw K. Binienda
______Committee Member Interim Dean of the College Dr. Stephen E. Duirk Dr. Craig Menzemer
______Committee Member Acting Dean of the Graduate School Dr. Richard L. Einsporn Dr. Marnie M. Saunders
______Date
ii
ABSTRACT
Lake Erie is a drinking water source for millions of people and therefore requires protection from anthropogenic impacts. Nine percent of Lake Erie’s freshwater comes from its tributaries. These sources should deliver clean water to the lake and thus warrant stewardship. Today, nonpoint sources emanating from agricultural and urbanized tributary watersheds are responsible for nutrient pollution loads to the lake and its tributaries.
This thesis focused on the existing water quality parameters (nutrients and water chemistry) throughout the Euclid Creek watershed, an urbanized Lake Erie headwater tributary east of the Cuyahoga River. Field sampling was conducted from
March 2019 to March 2020 at 14 sites with 23 dry weather collections and 11 wet weather collections. Results suggest that the 2019 annual phosphorus load entering Lake
Erie was 22,600 pounds, over four times the target of 5000 pounds.
Multiple upstream sites were the major nonpoint sources of nutrient pollution.
Four locations averaged phosphorus levels 12 to 15 times the target of 0.05 mg/L, with two in the East Branch and two in the Main Branch. The main cause of the pollution pointed to leaky sanitary sewers.
Like many urbanized areas throughout the United States, the original headwaters have been replaced by underground stormwater infrastructure. Due to the high level of
iii connectivity between the creek and the storm sewer network, Euclid Creek responds rapidly to rainfall. There was evidence of Combined Sewer Overflow (CSO) and Sanitary
Sewer Overflow (SSO) activations during storm events downstream of the confluence of the two branches and in the East Branch. Seasonally, spring storms contributed the most pollution during the monitoring period.
The presence of the Cleveland Metroparks significantly reduced [푝 < 0.05] nutrients during dry weather. Residential areas contributed more pollution than the three golf courses and the regional airport located within the watershed. The East Branch has little protection from urban run-off. This research suggests that water quality improvements are needed in both upstream branches. Autosamplers should be installed for future water quality monitoring at the two upstream existing US Geological Survey stations to gather data during wet weather events and baseflow conditions. Fish rocks, protective cave-like features, should be installed at upstream sites to protect aquatic life from storm-induced currents. If possible, storage for wet weather flows should be provided for both branches.
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ACKNOWLEDGEMENTS
I would like to express my deepest gratitude to Dr. Teresa J. Cutright, my advisor, for her unwavering guidance and support throughout this research work. Her encouragement and helpful critiques were invaluable. I am grateful for everything: laboratory and field equipment use, weekly update meetings, abundant reference material, expert chemical advice, and the pivotal opportunity to expand my engineering knowledge. Additionally, I would like to acknowledge the help provided me by Dr.
Richard L. Einsporn. His statistical expertise and advice were greatly appreciated throughout my research process. I would also like to express my appreciation to Dr.
Stephen E. Duirk, for his wisdom, time, and review of this work.
My special thanks are extended to Michael Spade, who generously helped with a plethora of laboratory analysis and George Carleton, who skillfully trained me in proper lab procedures and assisted with my initial field collection. I would also like to thank
Elizabeth Hiser, the Euclid Creek Watershed Program Manager, for her time and communication. I wish to thank everyone who helped me in the field collecting data for this research, during all types of weather. Thanks to Caroline Kelemen, my sons,
Cameron and Ethan, and Anne Wiles. Thanks to Elena Stachew, who donated the turbidity tube and to Patricia Eaglewolf, who was always available for help in the Civil
Engineering office. Finally, I wish to thank my husband, Tony, for all his support.
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TABLE OF CONTENTS
LIST OF TABLES……………………………………………………………………………………………………………………...…..xi
LIST OF FIGURES……………………………………………………………………………………………………………………….xiii
CHAPTER
I. INTRODUCTION………………………………………………………………………………………………………………….…….1
1.1 Water Pollution Background……………………………………………………………………………………….1
1.2 Euclid Creek Watershed……………………………………………………………………………………………..4
1.3 Objectives………………………………………………………………………………………………………………………..5
II. LITERATURE REVIEW…………………………………………………………………………………………………………..7
2.1 Lake Eutrophication……………………………………………………………………………………………………..7
2.2 Harmful Algal Blooms………………………………………………………………………………………………….9
2.3 Lake Erie………………………………………………………………………………………………………………………..10
2.4 Euclid Creek……………………………………………………………………………………………………………..….13
2.5 Dry Weather & Wet Weather Definitions……………………………………………………………14
III. HISTORICAL WATER QUALITY SAMPLING & RAINFALL…………………………….…….16
3.1 Rainfall Event Summary for the 2019-2020 Monitoring Period…….…………………..16 vi
3.2 Water Quality Monitoring & Assessment Reporting………………………………………..25
3.3 NEORSD Sampling…………………………………………………………………………………………………….29
3.4 The Euclid Creek Watershed Program……………………………………………………………….….31
3.5 Historical Rainfall Data Exploration………………………………………………………………………32
IV. EXPERIMENTAL METHODS……………………………………………………………………………………………..38
4.1 Overview of Site Selection Process………………………………………………………………………….38
4.2 Sampling Site Descriptions……………………………………………………………………………………...40
4.2.1 Acacia…………………………………………………………………………………………………………...40
4.2.2 Telling Mansion………………………………………………………………………………………...43
4.2.3 Schaefer Park………………………………………………………………………………………………45
4.2.4 Spencer Road……………………………………………………………………………………………..46
4.2.5 Harris Road…………………………………………………………………………………………………48
4.2.6 Community Center……………………………………………………………………………………50
4.2.7 U/S Stonewater……………………………………………………………………………………………51
4.2.8 Rockefeller Road………………………………………………………………………………………..52
4.2.9 Bishop Road………………………………………………………………………………………………..54
4.2.10 Richmond White……………………………………………………………………………………..55
4.2.11 Highland Main…………………………………………………………………………………………..56 vii
4.2.12 Highland East……………………………………………………………………………………………58
4.2.13 Villaview……………………………………………………………………………………………….……59
4.2.14 Wildwood……………………………………………………………………………………………….…61
4.3 Field Equipment………………………………………………………………………………………………………….62
4.4 Lab Analyses…………………………………………………………………………………………………………..……64
4.5 Statistical Methods…………………………………………………………………………………………………....65
V. DRY WEATHER RESULTS & DISCUSSION……………………………………………………………..……67
5.1 Dry Weather Flow Overview……………………………………………………………………………………67
5.2 Dry Weather Flow Conditions at Acacia……………………………………………………………...68
5.3 East & Main Branch Comparison……………………………………………………………………………78
5.4 Tributary Impact on East & Main Branches………………………………………………...……...81
5.5 Active Storm Sewer Collections During Dry Weather……………………….…….…….….89
VI. WET WEATHER RESULTS & DISCUSSION……………………………………………………………..…91
6.1 Wet Weather Overview………………………….…………………………………………………………….…...91
6.2 Wet Weather Flow Conditions at Acacia…………………………………………………………….92
6.3 Rainfall Characteristics of Wet Weather Collection Events……………………..…….101
6.4 East & Main Branch Comparison During Wet Weather for Upper and Lower Reaches………………………………………………...…………….……106
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6.5 Tributary Impact on Nutrient Concentrations of the Two Branches During Wet Weather…………………………………………………………………..……..109
6.6 Wet Weather Collections at Single Sites……………………………………………………………..112
VII. TOTAL PHOSPHORUS LOADING ANALYSIS……………………………………………..……………128
7.1 USGS Stations……………………………………………………………………………………………………….……128
7.2 Dry Weather Phosphorus Loading Calculations…………………………………………...……131
7.3 Wet Weather Phosphorus Loading Calculations………………………………………….…..133
7.4 Total Annual Phosphorus Loading Conclusion……………………………………………….…135
VIII. CONCLUSIONS AND RECOMMENDATIONS………………………………………………………..136
8.1 Conclusions………………………………………………………………………………………………………….……..136
8.2 Recommendations………………………………………………………………………………………..…………..141
REFERENCES…………………………………………………………………………………………………………………….…………145
APPENDICES………………………………………………………………………………………………………………………………..158
APPENDIX A: Dry Weather Results (Individual Sites) ………………………………..………159
APPENDIX B: Dry Weather East and Main Branch Comparison……………………..….186
APPENDIX C: Dry Weather ANOVA and Tukey Comparisons of Upstream Tributary Impact……………………………………………………………………………..…...…196
APPENDIX D: Wet Weather Results (Individual Sites)…………………………….……….…201
APPENDIX E: Wet Weather Collection Events……………………………………………………...228 ix
APPENDIX F: Phosphorus and Rainfall Characteristic Comparison………………………………………………………………………………………………………………………237
APPENDIX G: Wet Weather East and Main Branch Comparison……………………………………………………………………………………………………………………..243
APPENDIX H: Wet Weather ANOVA and Tukey Comparisons of Upstream Tributary Impact…………………………………………………………..………………………..249
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LIST OF TABLES
Table Page
2.1 Trophic States for Water Bodies……………………………………………………………………………….…..…7
2.2 US Lake Survey for Cyanobacteria…………………………………………………………………………….…..10
2.3 Target Nutrient Concentration Goals for US Streams…………………………….………………..13
2.4 2006 Existing TMDL Calculations for Euclid Creek Watershed…………………….……..14
3.1 Summary of Rain Events During 2019-2020 Monitoring Period……………………………..17
3.2 Summary of Rainfall Duration and Depth for 2019-2020 Monitoring Period…………………………………………………………………………………………………………....22
3.3 Comparison of 2019-2020 Monitoring Period Rainfall to Historical Data………………………………………………………………………………………………………………22
3.4 NEORSD Beachwood Rain Gauge Data (2012-2020)……………………………..………………..24
3.5 Monthly Rainfall Characteristics for the 2019-2020 Monitoring Period………………………………………………………………………………………………………..…..25
3.6 2018 NEORSD Nutrient Results for Euclid Creek…………………………………………..………..30
3.7 Summary Statistics for Matched-Pairs t-test Between Rain Gauges (2012-2019)…………………………………………………………………………………………..…….34
3.8 Difference in Monthly Rain Gauge Totals (Beachwood – CLE Airport)………………………………………………………………………………………….34
xi
5.1 Dry Weather Phosphorus Comparison for Upper Reaches of East & Main Branches……………………………………………………………………..………………………….78
5.2 Dry Weather Phosphorus Comparison for Lower Reaches of East & Main Branches…………………………………………………………………………………………….…..79
5.3 Summary Statistics for East & Main Branches During Dry Weather……………………………………………………………………………………………………………………….81
5.4 Site Descriptions for Adjacent Phosphorus Drop Comparison…………………………..…..87
5.5 Active Dry Weather Storm Sewer Nutrient Concentrations…………………………………..90
6.1 Peak Flow Differences in Branches During Wet Weather Events…………………….……………………………………………………………………..………..104
6.2 Summary Statistics for East & Main Branches During Wet Weather…………………………………………………………………………………………………………...... 108
6.3 Site Descriptions for Adjacent Phosphorus Drop Comparison……………………………………………………………………………………………………….……………...110
7.1 2019 Dry Weather Annual Predicted Phosphorus Loads for Euclid Creek……………………………………………………………………………………………………..……………...133
7.2 2019 Wet Weather Annual Predicted Phosphorus Loads for Euclid Creek……………………………………………………………………………………………………………..………135 .
7.3 2019 Total Annual Projected Phosphorus Loads for Euclid Creek…………………..………………………………………………………………………………………………...135
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LIST OF FIGURES
Figure Page
2.1 Satellite image of 2011 Lake Erie algal bloom…………………………………………………….………....11
2.2 Average Annual Total Phosphorus Inputs to Lake Erie
(2003 – 2011)……………………………………………………………………………………………………………………....12
3.1 Summary of 2019-2020 Rainfall Events: Depth and Duration………………………….……..23
3.2 Summary of 2019-2020 Rainfall Events: Antecedent and Rainfall Intensity………………………………………………………………………………………………………….……23
3.3 Impairment Causes for US Waters………………………………………………………………………….……26
3.4 Aquatic Life Attainment for Ohio’s Wading & Principal Streams………………………………………………………………………………………………………………………….....…27
3.5 Priority Ranking of Ohio Watersheds………………………………………………………….………………28
3.6 Euclid Creek Volunteer Phosphorus Monitoring Data (2006-2019)………………………………………………………………………………………………………………………..32
3.7 NOAA and NEORSD Rain Gauge Locations……………………………………………………….………33
3.8 Historical Monthly Trends at Cleveland Hopkins Airport (1939-2019)………………………………………………………………………………………………………….………………35
3.9 Beachwood Rain Gauge Monthly Rainfall Totals (2012 – 2019)………………………………………………………………………………………………………………………36
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3.10 Annual Means at Cleveland Hopkins Airport and Mean of all NEORSD Rain Gauge Data (2013-2019)………………………………………………………………….……37
4.1 Sampling sites used to assess water quality in Euclid Creek Watershed……….………………………………………………………………………………………………………….……..40
4.2 Acacia Site Views: (a) looking downstream from pedestrian bridge and (b) looking at sampling site from downstream location……………………………………………………………………………………………….……….42
4.3 Storm drains at Acacia on Eastern Embankment……………………………………….….….………42
4.4 Telling Mansion Site Views: (a) looking downstream from pedestrian bridge and (b) looking at sampling site from downstream location…………………………………………………………………………………………….………...44
4.5 Possible iron deposit area downstream of Telling Mansion Site…………………………….44
4.6 Land use surrounding unnamed tributary to Main Branch…………………………..…………45
4.7 Schaefer Park Site Views: (a) looking at sampling site from downstream location and adjacent storm sewer and (b) second storm sewer on downstream opposite embankment…………………………………………..……46
4.8 Schaefer Park Investigation Locations………………………………………………………………….………47
4.9 Downstream View at Spencer Road Site…………………………………………………………….……….48
4.10 East Branch Investigation Sample Locations………………………………………………………….…..49
4.11 Harris Road Site Looking Upstream…………………………………………………………………………….49
4.12 Community Center Site looking upstream………………………………………………………………….50
4.13 Community Center Site Views: (a) looking at storm sewer at site and (b) looking at second storm sewer downstream of site…………………………………………………………………………………………..…………….….51
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4.14 U/S Stonewater Site Views: (a) looking upstream from sampling site with storm drains further upstream and (b) looking upstream from site with storm sewer at sampling site………………………………………………………………………………………………………………………………………..52
4.15 Upstream view of Rockefeller Road Site…………………………………………….……………………….53
4.16 Bishop Road Site Views: (a) upstream view of tributary and (b) storm sewer at sampling site, downstream side of bridge………………….……….…….55
4.17 Richmond White Site Views: (a) upstream of East Branch at sampling site and (b) looking downstream at the sampling site from upstream location……………………………………………………………………………………….……56
4.18 Highland Main Site Views: (a) looking at sampling site and (b) looking upstream from sampling site………………………………………………………….…………58
4.19 Highland East Site Views: (a) downstream view of the confluence of the two branches and (b) looking upstream from site………………………………………………………………………………………………………………………………59
4.20 Villaview Site Views: (a) looking at sampling site from downstream side and (b) looking downstream from sampling site………………………………………………………………………………………………….……………..……60
4.21 Wildwood Site Views: (a) looking upstream from sampling site and (b) storm sewer at sampling site, upstream side………………………………………..………61
4.22 Turbidity tube used to determine stream characteristics…………….………………………….62
4.23 Measuring turbidity: (a) looking into the tube to view Secchi disk for unclear water (b) Looking at the tube filled with clear water……………………………………………………………………………………………………………………………….……63
4.24 Multiparameter Probe used to determine stream characteristics: (a) Typical reading in bucket completed at all site locations (b) Back-up stream reading completed at sites where access to direct stream sampling possible………………………………………….….64
4.25 Typical glass vial used for laboratory testing…………………………………………………….…..……65
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5.1 Acacia: Dry Weather Phosphorus Mean and Standard Deviation Levels over Time Based on Triplicate Samples……………………………………………………………68
5.2 Dry Weather Nitrate Mean and Standard Deviation Levels over Time Based on Triplicate Samples Comparison for Old and New Colorimeter……………………………………………………………………………………….………69
5.3 Acacia: Dry Weather Nitrate Mean and Standard Deviation Levels over Time Based on Triplicate Samples………………….……………………..70
5.4 Acacia: Dry Weather pH levels over time…………………………………………………..………………..72
5.5 Acacia: Dry Weather Conductivity levels over time……………………………………..…………..73
5.6 Dry Weather Conductivity vs. Water Temperature at Acacia………………………….…….74
5.7 Acacia: Dry Weather Turbidity levels over time………………………………………………….……..76
5.8 Acacia: Dry Weather Water temperature levels over time…………………………….………..76
5.9 Acacia: Relationship between Water and Air Temperature During Dry Weather………………………………………………………………………………………………………...77
5.10 Dry Weather Phosphorus Level Comparison Between Original Nine Sites…………………………………………………………………………………………………………...82
5.11 Existing Sanitary Sewer Line at Schaefer Park Site…………………………………………………..83
5.12 Schaefer Park Investigation Phosphorus Results………………………………………………….……84
5.13 East Branch Tributary Investigation Phosphorus Results……………….………………………85
5.14 Location of Three Upstream Tributary Sites for East Branch……………….………………..85
5.15 Adjacent Site Phosphorus Drop Comparison…………………………………………………….……….87
5.16 Mapping of Change in Phosphorus Concentrations for Adjacent Sites During Dry Weather Conditions………………………………………….…………….88
5.17 Active Storm Sewer During Dry Weather at Telling Mansion………..…………..…………90
6.1 Acacia: Phosphorus concentrations during wet weather events. Standard deviation based on triplicate samples………………………………….……………………..92
6.2 Acacia: Nitrate concentrations during wet weather events. Standard deviation based on triplicate samples…………………………………………….…..………94
xvi
6.3 Acacia: pH levels over time during wet weather events……………………………………………96
6.4 Acacia: Conductivity levels over time during wet and dry weather……………………….97
6.5 Looking downstream from Acacia sampling site (a) during wet weather conditions on June 20, 2019 and (b) stone debris during September 15, 2019 collection…………………………………..……………….…….……99
6.6 Acacia: Turbidity levels over time during wet weather………………………………………..…100
6.7 Acacia: Water temperature levels over time during wet weather…………………………………………………………………………………………………………………………….…101
6.8 All wet weather events for the monitoring period (March 2019 – March 2020)…………………………………………………………………………………….……102
6.9 Wet Weather Collection 1: Main Branch at Telling Mansion (April 26, 2019)………………………………………………………………………………………..……..103
6.10 Wet Weather Collection 1: East Branch at Richmond White (April 26, 2019)……………………………………………………………………………………………………104
6.11 Wet Weather Conditions for East Branch at Richmond White: Phosphorus Concentration vs Rainfall based on triplicate samples…………………………………………………………………………………………………..………..106
6.12 Adjacent Site Phosphorus Drop Comparison During Wet Weather………………………………………………………………………………………………………………………..……110
6.13 Mapping of Change in Phosphorus Concentrations for Adjacent Sites During Wet Weather Conditions…………………………………………….……..…111
6.14 Rainfall and Discharge During the Monitoring Period for the July 16-17th storm event for the (a) Main Branch and (b) Main Branch and East Branch…………………………………………………………………………………114
6.15 Changes in (a) Mean Phosphorus Concentration and (b) Mean Nitrate Concentration at Highland Main During July 17th Rain Event. Standard deviations based on triplicate sampling………………………………………………………………………………………………………………………..……115
6.16 Changes in (a) Mean Phosphorus Concentration and (b) Mean Nitrate Concentration at Highland Main and Highland East (c) Turbidity at Highland Main and Highland East During July 17th Rain Event. Standard deviations based on triplicate sampling…………………………………………………………………………………………….….……117
xvii
6.17. Monitoring period within the July 22nd rain event at Schaefer Park………………..…………………………………………………………………………………….………….…119
6.18 Water quality concentrations over time at Schaefer Park during July 22nd rain event: (a) Mean Phosphorus Levels (b) Mean Nitrate Levels. Standard deviations based on triplicate sampling (c) Turbidity and Conductivity (d) pH and Temperature……………………………………………………………………………………….….……120
6.19 July 22, 2019 Rain Event at Schaefer Park Illustrating (a) Rainfall Intensity (b) Main Branch Discharge at USGS Station 04208677…………………………………………………………………………………………………..…………122
6.20 October 30th Rain Event at Schaefer Park with (a) Total 2-Day Storm Discharge (b) Discharge and Rainfall Intensity for the monitoring period…………………………………………………………………………………….……..…124
6.21 Changes in (a) Mean Phosphorus and (b) Mean Nitrate Concentrations at Schaefer Park during October 30th rain event. Standard deviations based on triplicate sampling…………………………………..……125
6.22 Changes in (a) pH Levels, (b) Conductivity and (c) Temperature during October 30th Rain Event at Schaefer Park…………………………………………………………………………………………………………..……127
7.1 March 2019 – March 2020 Annual Discharge for Euclid Creek’s (a) East Branch (b) Main Branch, and (c) Downstream after Confluence of Two Branches…………………………………………………………………………….…130
7.2 Monitoring Stations used for pollutant loads…………………………………..…….…………….……131
7.3 Linear Regression Equations for Dry Weather Phosphorus Loads for (a) East Branch, (b) Main Branch, and (c) Downstream after the Confluence of the Two Branches……………………..……..……132
7.4 Linear Regression Equations for Wet Weather Phosphorus Loads for (a) East Branch, (b) Main Branch, and (c) Downstream after the Confluence of the Two Branches……………………..………..…134
8.1 Fish rocks designed by Professors Vogl and Benitez to protect fish from heavy storm flows…………………………………………………………………….…..…144
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CHAPTER 1
INTRODUCTION
1.1 Water Pollution Background
Chronic pollution in surface waters continues to plague the planet and threaten human health. Current stormwater and wastewater practices allow contaminants to freely enter drinking water sources (Holt, 2000). Headwater streams tributary to drinking water sources require protection. Since the Industrial Revolution, the manufacturing of goods alongside human migration to cities has caused widespread environmental pollution to waterways. Environmental public policy is headed toward more sustainable practices, balancing economic, social, and environmental principles
(Haque and Ntim, 2018; Lu et al., 2015; Costanza et al., 2016). Governments focused on intergenerational environmental ethics is necessary; without it, the planet’s natural resources are expended until extinction (Lockwood, 1874).
People have long suspected that urban run-off from storm events causes damage to the environment. During the 1800’s, surface run-off from the railroads was observed in local rivers and thought to cause harm to aquatic life (Lockwood, 1874). Similarly, human waste was known to contaminate drinking water, causing cholera, dysentery, typhoid fever and diarrhea (Vuorinen et al., 2007). By 1900, water closets were deemed necessary to protect public health in urban households, but there was still no thought
1 given to improve the sanitation process for domestic waste removal (Vuorinen et al.,
2007). American cities followed sanitation practices already developed throughout much of Europe. Sanitary sewers provided direct transportation routes for waste from individual city households to nearby rivers. Given these infrastructure origins, today’s stormwater and sanitary sewer systems have improved, but still negatively impact the environment.
Stormwater pipes continue to act as direct conduits between urban impervious surface areas and streams. Although today’s sanitary sewers now act as connections between individual homes and wastewater treatment plants instead of nearby rivers, the aging infrastructure steadily leaks into the surrounding environment (Lee et al., 2015;
Sercu et al, 2011; Kaushal & Belt, 2012). Additionally, and just as problematic, sanitary sewer flow volumes and rates have increased due to high infiltration and inflows. As a result, large interceptor tunnels have been constructed worldwide to capture and hold these vast quantities until processed at wastewater treatment facilities. Even with this supplementary infrastructure, exfiltration to nearby rivers continues to occur.
According to the United States Environmental Protection Agency (US EPA,
2020a), stormwater run-off can contain phosphorus and nitrogen, pathogens, petroleum hydrocarbons, metals, sediment, pesticides, herbicides, and organics. Sewage generally consists of organic matter, inorganic salts, heavy metals, bacteria, viruses, phosphorus and nitrogen. These contaminants can escape either through pipe leaks or by intentional overflow designs. Excess amounts of phosphorus and nitrogen are key contributors to harmful algal blooms (HABs). An added concern is that excess amounts of phosphorus and nitrogen increase biological activity which eventually leads to eutrophic conditions
2 in waterbodies. The excessive algae growth triggered by these nutrients can cause HABs.
It is difficult and costly to remove the toxins from HABs. In 2013, the Ohio EPA decreed
“do not drink” advisories due to increased cyanobacterial HABs in Lake Erie. In 2014,
Toledo, Ohio had to issue a ban on drinking and cooking with tap water (Fitzsimmons,
2014). Microcystins are a type of cyanotoxin from HABs that can cause illness or death if ingested (US EPA, 2020b). Lake Erie HABs usually contain Microcystis colonies (National
Oceanic and Atmospheric Administration (NOAA), 2020a). Heavy rains and sewer overflows push excess nutrients into the lake. HABs occur throughout the Great Lakes, from the western edge of Lake Superior to the eastern portion of Lake Ontario. This past year, 2019, was one of the strongest HAB activity in the Western Basin (Briscoe, 2019;
NOAA, 2020b). Cyanobacteria have been tested and confirmed at Cleveland beaches during this time (Johnston, 2019; Justice, 2019).
The United Nations estimates approximately 80% of global wastewater is released without proper treatment (United Nations Educational, Scientific and Cultural
Organization (UNESCO), 2017). Water pollution originates at point and nonpoint sources. In the United States, point sources are regulated by the US EPA through the
Clean Water Act. Nonpoint sources are comprised of at least one unknown point source.
The EPA states that nonpoint sources are the most significant source of water pollution.
Although there are no directly stipulated regulations, cities and states are required to develop nonpoint source pollution management programs to obtain any federal funding
(US EPA, 2020c).
In local urban environments, water pollution occurs every day. Pollution amounts are dependent on weather conditions. During rain events, pollution enters surface waters
3 from direct connections with stormwater infrastructure and combined sewer overflow
(CSO) and sanitary sewer overflow (SSO) activations. During dry weather, pollution enters surface waters from National Pollutant Discharge Elimination System (NPDES) connections, illicit discharges, and leaky sanitary sewers.
1.2 Euclid Creek Watershed
According to the US EPA, Lake Erie provides drinking water for approximately 11 million people with most of the inflow for Lake Erie (~80%) coming from the Detroit
River (US EPA, 2020d). Of the remaining 20%, about half, 11%, comes from precipitation and 9% comes from tributaries (US EPA, 2020d). The Lake Erie Watershed has a total drainage area of 30,140 square miles (Augustyn, 2019).
In total, there are 34 watersheds tributary to Lake Erie, 26 in the United States and 8 in Canada. Euclid Creek lies within the Ashtabula-Chagrin Watershed Region
(Hydrological Unit Code 04110003). It is one of the most urbanized of the Lake Erie sub watersheds. The majority of Euclid Creek lies within Cuyahoga County, Ohio. It is approximately 43 miles long and drains approximately 24 square miles (Euclid Creek
Watershed Program, 2018). The Main Branch of the creek extends from its headwater location in the community of Beachwood to its downstream location at Wildwood Park, where the mouth of the creek meets Lake Erie in Cleveland. Between these two endpoints, the Main Branch travels through two additional communities, Lyndhurst and
South Euclid. A substantial portion of the watershed flows into the East Branch of the creek. This branch has its headwater location in Highland Heights and Willoughby Hills
4
(Lake County). The East Branch travels through the town of Richmond Heights and
Euclid before its confluence with the Main Branch.
Euclid Creek is in an Area of Concern for Lake Erie. The Great Lakes Water
Quality Agreement outlined fourteen beneficial uses to restore tributary rivers of the
Great Lakes back to good ecological health. Although not tributary to the Cuyahoga
River, it is listed as part of the Cuyahoga River Area of Concern by the International
Joint Commission (Cuyahoga River Restoration, 2020; International Joint Commission,
2020). The main water quality impairments of Euclid Creek are high nutrients, low fish populations, embankment erosion and illicit discharges (Ohio EPA, 2005).
There is evidence of continued pollution via sewer leakage through the water quality efforts at downstream beaches by the USGS Great Lakes NowCast Status. Villa
Angela Beach conditions were tested daily for Escherichia coli (E. coli) counts by the
Northeast Ohio Regional Sewer District (NEORSD). During the summer of 2019, 39% of the days that reported counts exceeded the beach action value of 235 most-probable number/100 ml (USGS, 2020a). These high-count days are not all associated with rainfall, suggesting that pollution occurs during dry weather as well as wet weather.
1.3 Objectives
The overall intent of this research was to gather reliable water chemistry, analyze the results, and make recommendations to reduce the pollution of a tributary to Lake
Erie, a local drinking water source. This research focused on gathering detailed information on nutrient levels. Hypothesis: The nutrient levels for Euclid Creek will be
5 highest downstream during the warmest part of the summer. There are three additional sub-objectives of this work:
1. Collect water quality data at the established volunteer Euclid Creek
Watershed monitoring locations in order to compare results with historical
data. Hypothesis: Nutrient levels relative to the spatial orientation within the
watershed will be akin to past conditions. New patterns are expected to
emerge since this is the first-time data has been collected at all monitoring
locations consecutively within the same day.
2. Monitor water quality during wet and dry conditions to establish baseline
conditions for wet weather impacts. Hypothesis: Nutrient levels during dry
weather will be low. Wet weather collections during storm events will be
compared to dry, baseline conditions. Collections will be made for wet
weather samples at all locations within a day as well as monitoring a wet
weather event at a single location. Wet weather nutrient levels will be
dependent upon the rainfall amount, rainfall intensity, and time of collection
within the storm event. Nutrient levels are expected to rise after the initial
rainfall, then dilute after the peak flow.
3. Determine the importance of land use as a factor on nutrient levels. Hypothesis:
The highest nutrient levels will occur downstream of golf courses and the
airport. The lowest nutrient levels will occur at upstream residential
headwater locations.
6
CHAPTER 2
LITERATURE REVIEW
2.1 Lake Eutrophication
Lakes naturally age over time, typically living hundreds, if not thousands, of years. Over time, a lake’s basin fills with sediment and nutrients (Dunn, 1989).
Ultimately, plants and algae proliferate, depleting dissolved oxygen levels and ending the lake’s life. This process is called natural eutrophication and occurs slowly, over a long period of time. Anthropogenic eutrophication is an artificial increase in the supply rate of organic matter to an ecosystem (Nixon, 1995). This increased organic carbon supply can be caused by increased inorganic nutrients, decreased water turbidity, change in hydraulic residence time, change in land use, and increased organic matter (Hinga et al.,
1995). The acceleration of an organic carbon supply can change the trophic state of the water body (Hinga et al., 1995). There are four basic trophic states as shown in Table 2.1.
Table 2.1. Trophic States for Water Bodies Trophic State Organic Carbon Supply (gC / m2/yr) Oligotrophic ≤100 Mesotrophic 101 – 300 Eutrophic 301 – 500 Hypertrophic › 500 Source: Hinga et al., 1995
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Lake longevity varies due to differences in surface area, depth, stored volume, shoreline length, temperature, rainfall, and river inflow (Messager et al., 2016; Scavia et al., 2014). Lake maturity is based on its physical and chemical properties. The main physical characteristics are temperature, light, rainfall and wind, while the main chemical characteristics are biological, geological, and human processes (US EPA, 2020e;
National Geographic, 2020). Pollution, caused by human processes, can shorten a lake’s life dramatically. Key sources of pollution are acid rain, nutrient pollution, fish stocking, pesticide poisoning, invasive species, soil erosion, road salt, and climate change (Stager,
2018). Anthropogenic eutrophication can occur over a very short period, ending a lake’s life in decades.
A healthy lake ecosystem uses nitrogen and phosphorus as a food source for nutrient-rich plants and algae. In turn, these plants and algae become the food source for other organisms living in lakes. This natural food chain can become disrupted when a lake’s chemistry is artificially changed by humans. Sewage, storm run-off, and fertilizers can enter surface waters from nonpoint sources like lawn applications, accidentally from leaks. This additional volume of flow contains nutrients that can be easily consumed by microscopic algae as well as deposited in sediments. These organisms can multiple and create large algal blooms, a major environmental problem in all 50 US states (US EPA,
2020f). Algal blooms can deplete a lake’s oxygen level, block sunlight, and clog fish gills
(NOAA, 2020a). A small percentage of these blooms, less than one percent, release toxins that are harmful to the environment and humans (NOAA, 2020c).
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2.2 Harmful Algal Blooms
Most algal blooms are beneficial, providing a food source for other organisms like bivalves and fish. They also provide almost half of the world’s photosynthesis (Rossini,
2014). There are 5,000 species of planktonic algae. About 300 species can cause discoloration of surface water and 80 species can produce toxins (Rossini, 2014). In freshwater, cyanobacteria are usually responsible for large blooms (CDC, 2020). When environmentally stressed, these blue-green algae can produce microcystin, a toxin that cause a variety of health problems to humans, from dermatitis to nerve damage (Rossini,
2014; USGS, 2016). As stated in Section 1.1, when a bloom contains cyanobacteria, it is designated as a HAB. HABs can also cause other problems including unpleasant taste and odor, a blue-green, yellow, red or brown water discoloration, anoxic conditions for other aquatic life, and unfavorable economic impacts (USGS, 2016).
Nutrient loading distribution is a key factor in forming HABs, as the cyanobacteria use phosphorus and nitrogen as a food source (Gilbert et al., 2005).
Nutrients can be delivered intermittently and intensely by heavy rainfall or continuously and slowly by sewer discharge (Gilbert et al., 2005). Other factors include time of year and the presence of competitor or consuming species. Predicting HAB occurrence is a current goal for the science community (USGS, 2016). The US EPA prioritizes watersheds within each state to target nutrient load reductions (US EPA, 2020g).
In 2007, the US EPA completed a lake assessment for all 50 contiguous states to help understand the number of lakes impacted by HABs. According to the World Health
Organization (WHO), when a water quality sample exceeds 20,000 cells per milliliter
(mL) of cyanobacteria, the water becomes a health risk. Scum formation occurs at
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100,000 cells/mL (WHO, 2003). Table 2.2 details the ten states in the 2007 US EPA survey with the highest percentage of positive lake tests, a lake sample in excess of
20,000 cells/mL (US EPA, 2009). Samples were taken at the deepest part of each lake in an order to minimize false positives. The number of lakes tested in each state varied from
7 lakes to 66 lakes. Positive cyanobacteria tests occurred in 79% of states tested. Of the states that had positive lake results, over half had cyanobacteria in at least 20% of lakes tested. Ohio ranked 19th with 27% positive (6 out of 22 lakes).
Table 2.2. US Lake Survey for Cyanobacteria Percent of Lakes Number of Lakes Total Number of State Tested Positive Tested Positive Lakes Tested South Dakota 71% 29 41 Illinois 62% 13 21 North Carolina 52% 11 21 North Dakota 52% 23 44 Missouri 46% 13 28 Texas 46% 26 56 Delaware 44% 4 9 Virginia 42% 11 26 Indiana 39% 22 56 Idaho 37% 13 35 Source: US EPA, 2009
2.3 Lake Erie
Algal blooms were a common occurrence in Lake Erie during the 1950’s and
1960’s. Phosphorus loading from farms and sewage plants permeating into Lake Erie’s tributaries was the main factor adversely impacting Lake Erie during that time
(European Space Agency (ESA), 2020). In 1972, The Great Lakes Water Quality
Agreement implemented phosphorus limits and water quality improved. Unfortunately, by the mid-1990’s, nutrient enrichment conditions returned, especially noted by the
10 increased presence of cyanobacteria (Scavia et al., 2014). Figure 2.1 shows an ESA (2011) satellite image of a 2011 bloom. The re-eutrophication of Lake Erie in recent times has worsened in three ways. The Western Basin has seen the most frequent cyanobacteria blooms, with the Maumee River contributing the highest phosphorus loads. The Central
Basin experiences hypoxia and the Eastern Basin experiences nuisance blooms (Annex 4,
2015).
Figure 2.1. Satellite image of 2011 Lake Erie algal bloom Source: Envistat, ESA, 2011
Regulations effectively decreased point source total phosphorus (TP) loads, leaving nonpoint sources as the primary phosphorus source (Scavia et al., 2014). As
Figure 2.2 shows, during the first part of the 2000’s, nonpoint phosphorus inputs tripled point sources, the second leading major nutrient source. Lake Erie receives the most TP
11 from the Western Basin (60%). The Central Basin contributes about 30%, with the remaining 10% coming from the Eastern Basin (Scavia et al., 2014).
Upstream (Lake Huron) 4%
Atmospheric 6% Nonpoint 69%
Point 21%
Figure 2.2. Average Annual Total Phosphorus Inputs to Lake Erie (2003 – 2011) Source: Dolan and Chapra, 2012
Recently, dissolved reactive phosphorus (DRP) has been studied due to its bioavailability to cyanobacteria (Scavia et al., 2014). In the 1990’s, DRP represented about 11% of incoming TP loads from contributing watersheds to Lake Erie. A decade later, the level of DRP increased to 24% of incoming TP loads. It is now estimated that
DRP has increased 150% from the mid-1990’s levels (Annex 4, 2015). Although phytoplankton biomass decreased from 1970 to the mid 1980’s, the increased DRP loading has led to high abundances of cyanobacteria (predominantly Microcystis) in Lake
Erie. In order to reach improved water quality conditions, phosphorus levels need to be cut in half (Scavia et al., 2014). Modeling suggests that driving phosphorus loading rates
(i.e., the load associated with biomass increases) differs between the Western and
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Central Basins. Driving phosphorus loading occurs in the spring for the Western Basin, but annual loading is the driver for the Central Basin (Annex 4, 2015).
2.4 Euclid Creek
Euclid Creek is one of nearly 100 headwater streams tributary to Lake Erie
(Euclid Creek Watershed Council et al., 2006). The Euclid Creek Watershed is on
Ohio’s list of impaired waters (Ohio EPA, 2005). The Ohio EPA identified the pollution causes as nutrient enrichment, sedimentation, and stream habitat degradation (Euclid
Creek Watershed Council et al., 2006). The corresponding sources were CSOs, failing septic systems, stormwater run-off, and nonpoint sources (Ohio EPA, 2005). Since
Euclid Creek is classified as an impaired water, the Clean Water Act requires that pollutant limits must be developed and enforced. Total maximum daily loads (TMDLs) for impaired streams are designed to restore Euclid Creek by full attainment of water quality standards (US EPA, 1991). US stream target concentrations for phosphorus and nitrate-nitrite are listed in Table 2.3. (Euclid Creek Watershed Council et al., 2006).
Table 2.3. Target Nutrient Concentration Goals for US Streams Stream Type Watershed Area Phosphorus Nitrate-nitrite (mi2) Concentration Concentration (mg/L) (mg/L) Headwaters < 20 0.05 1.00 Wadable 20 – 200 0.07 1.05 Source: Ohio EPA, 2005
States are responsible for submitting TMDL calculations to the US EPA for all waters classified as impaired (US EPA, 2020h). The Ohio EPA used the following equation to calculate target phosphorus loads (Ohio EPA, 2005):
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푇푀퐷퐿 = ∑ 푊퐿퐴 + ∑ 퐿퐴 + 푀푂푆 Equation (1) where: WLA = waste load allocations (point sources)
LA = load allocations (nonpoint sources and background)
MOS = margin of safety (10%)
Using this approach, the approved WLA, LA, MOS, and TMDL were 0 lbs/yr, 4990.62 lb/yr, 554.41 lb/yr, and 5545.12 lb/yr, respectively (Ohio EPA, 2005). As of 2006, Euclid
Creek existing conditions exceeded target levels. Table 2.4 reveals that nonpoint source phosphorus levels were ten times as high as point sources. The phosphorus target reduction goal is 3450 pounds per year. In addition, the watershed implemented best management practices like obtaining conservation easements, establishing riparian setbacks, dam removals, and sustainable site design (Euclid Creek Watershed Council et al., 2006).
Table 2.4. 2006 Existing TMDL Watershed Calculations for Euclid Creek Watershed WLA LA LA Breakdown TMDL (lb/yr) (lb/yr) Surface Run- Baseflow (lb/yr) off 730.58 8439 8034.5 404.5 9169.58 Source: Euclid Creek Watershed Council et al., 2006
2.5 Dry Weather & Wet Weather Definitions
The Clean Water Act of 1972 requires all point sources discharging to US waters to have a permit through the NPDES. In 1990, the US EPA required water sampling as part of the permit application process (US EPA, 1992). During sampling it is important
14 to denote climate conditions (temperature, cloud cover, barometric pressure and amount/type of precipitation) as they can impact parameter levels.
To ensure dry weather conditions, sampling should be avoided during and immediately after a storm event. In most urban environments, stormwater run-off ends within 12 hours following the storm (Pitt, 2001). However, local knowledge and experience should be used to capture dry weather conditions as the time could extend past 12 hours due to upstream conditions (Pitt, 2001).
The US EPA defines a wet weather event as having a total depth of at least 0.10 inches of rainfall and an antecedent dry period of at least 72 hours (US EPA, 1992). The
US EPA states that whenever possible, representative rain events should not vary by more than 50 percent in terms of event duration and depth. This criterion was established in order to have measurable flow, a build-up of pollutants, and representative annual conditions (US EPA, 1992). Reliable local rainfall statistics should be used to characterize storm events throughout the year. Using these local statistics as well as annual NOAA statistics for US rain zones help define the representativeness of storm events (US EPA, 1992).
The US EPA discovered from past projects that dry weather flow conditions can contribute significant pollution loads to receiving waters (Pitt, 2001). The US EPA’s
Nationwide Urban Runoff Program (NURP) dry weather pollutant flows could be a result of directly connected illicit discharges or indirectly connected discharges like leaky sanitary sewer infiltration (US EPA, 1983). Conditions can also be quite different for warm and cold weather.
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CHAPTER 3
HISTORICAL WATER QUALITY SAMPLING & RAINFALL
3.1 Rainfall Event Summary for the 2019-2020 Monitoring Period
During this research collection period (March 2019 – March 2020), there were 71 events with at least 0.10 inches of rainfall. Table 3.1 describes each rain event. Rainfall data was acquired from the Northeast Ohio Regional Sewer District’s (NEORSD)
Beachwood Rain Gauge located at 2670 Richmond Road. A rain event begins with the initial storm onset, recording a rainfall depth of at least 0.01 inches in a 5-minute interval, and continues until the end of the event. A rain event ends when there is no rain recorded for twelve consecutive hours of time.
The NEORSD Rain Gauge is a tipping bucket, typically mounted on a building’s roof, that records depth in 5-minute intervals. Events highlighted in Table 3.1 were wet weather collection samples used for this research. Events highlighted in yellow were collections conducted at all sites and events highlighted in green were collections conducted at one site. The antecedent dry period denotes the time between rain events.
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Table 3.1. Summary of Rain Events During 2019-2020 Monitoring Period Event Date Start – End of Rainfall Storm Rainfall Ante- Event Depth Duration Intensity cedent (in) (hrs) (in/hr) Dry Period (hrs) 1 March 9 – 10 Mar 9 @ 7:10pm – Mar 10 @5:35 0.72 10.42 0.18 404.42 am 2 March 14 10:00am – 8:15 0.35 10.25 0.24 100.42 pm 3 March 22 7:00 am – 3:15 0.10 8.25 0.08 178.75 pm 4 March 29 3:25 am – 10:50 0.32 7.42 0.09 152.75 am 5 March 30 – 31 Mar 30 @ 1:45 1.47 31.5 0.26 14.92 am – Mar 31 @ 9:15 am 6 April 12 9:40 am -11:20 0.23 1.67 0.13 288.42 am 7 April 14 – 15 Apr 14 @ 4:10 0.70 26.83 0.25 16.84 am – Apr 15 @ 7:00 am 8 April 19 – 20 Apr 19 @ 5:55 1.29 27.42 0.26 123.42 am – Apr 20 @ 9:20 am 9 April 25 – 26 Apr 25 @ 5:25 1.02 24.58 0.21 128.08 pm – Apr 26 @ 6:00 pm 10 April 27 – 28 Apr 27 @ 8:20 0.40 10.17 0.10 14.33 pm – Apr 28 @ 6:30 am 11 April 29 2:50 pm – 7:55 0.49 5.08 0.21 32.33 pm 12 April 30 12:45 pm – 1:25 0.11 0.67 0.11 16.83 pm 13 May 1 – 2 May 1 @ 4:35 0.94 13.08 0.21 27.17 pm – May 2 @ 5:40 am 14 May 3 12:50 am – 1:20 0.10 12.50 0.03 19.17 pm 15 May 9 – 10 May 9 @ 1:50 0.51 15.25 0.13 144.50 pm – May 10 @ 5:05 am
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Event Date Start – End of Rainfall Storm Rainfall Ante- Event Depth Duration Intensity cedent (in) (hrs) (in/hr) Dry Period (hrs) 16 May 11 – 12 May 11 @ 10:30 0.30 5.33 0.12 40.58 pm - May 12 @ 3:50 am 17 May 12 – 13 May 12 @ 5:45 0.36 17.92 0.11 13.92 pm – May 13 @ 11:40 am 18 May 19 5:15 pm – 7:05 0.15 1.83 0.09 149.58 pm 19 May 26 8:05 am – 7:00 0.38 10.92 0.19 157.00 pm 20 May 27 – 29 May 27 @ 10:20 1.19 28.42 0.71 27.33 pm – May 29 @ 2:45 am 21 May 30 7:00 am – 5:00 0.59 10.00 0.41 28.25 pm 22 June 1 – 2 June 1 @ 8:15 0.43 6.25 0.16 27.25 pm – June 2 @ 2:30 am 23 June 4 – 5 June 4 @ 10:45 1.47 12.67 0.41 47.25 pm – June 5 @ 11.25 pm 24 June 10 1:20 am – 6:00 1.08 16.67 0.34 97.92 pm 25 June 12 – 14 June 12 @ 10:40 1.84 26.50 0.51 52.67 pm – June 14 @ 1:10 am 26 June 15 – 16 June 15 @ 1:55 1.45 26.75 0.40 36.75 pm – June 16 @ 4:40 pm 27 June 20 12:20 am – 11:30 1.84 23.17 0.86 79.67 pm 28 June 24 4:35 pm – 8:50 2.03 4.25 1.35 89.08 pm 29 June 28 6:50 pm – 7:15 0.26 0.42 0.26 94.00 pm 30 July 2 – 3 July 2 @ 9:50 0.58 6.5 0.48 98.58 pm – July 3 @ 4:20 am 31 July 4 12:05 pm – 5:50 0.15 5.75 0.13 31.75 pm
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Event Date Start – End of Rainfall Storm Rainfall Ante- Event Depth Duration Intensity cedent (in) (hrs) (in/hr) Dry Period (hrs) 32 July 16 – 17 July 16 @ 2:30 1.17 22.42 0.48 284.67 pm – July 17 @ 12:55 pm 33 July 20 4:35 am – 6:25 0.26 1.83 0.25 64.50 am 34 July 21 – 22 July 21 @ 8:30 0.40 13.42 0.26 38.08 pm – July 22 @ 9:55 am 35 July 30 12:00 am – 10:05 0.46 10.08 0.22 182.08 am 36 July 31 4:15 am – 4:25 0.19 0.17 0.19 18.17 am 37 August 6 – 7 August 6 @ 1.53 11.50 0.70 152.33 12:45 pm – August 7 @ 12:15 am 38 August 15 2:05 pm – 2:45 0.58 0.67 0.58 205.83 pm 39 August 18 5:15 am – 11:15 0.71 6.00 0.68 62.40 am 40 August 18 – 19 August 18 @ 0.31 2.00 0.26 12.25 11:30 pm – August 19 @ 1:30 am 41 August 22 1:20 am – 11:35 0.41 10.25 0.24 71.83 am 42 August 27 1:15 pm – 4:05 0.16 2.83 0.12 121.67 pm 43 September 1 6:10 am – 8:55 0.18 14.75 0.07 110.08 pm 44 Sept 11 – 12 Sept 11 @ 1:25 1.47 20.42 0.62 232.50 pm – Sept 12 @ 9:50 am 45 September 13 7:35 pm – 11:45 2.42 4.17 2.12 33.75 pm 46 October 2 – 3 Oct 2 @ 2:55 pm 0.32 14.17 0.11 423.17 – Oct 3 @ 5:05 am 47 October 6 – 7 Oct 6 @ 9:05 0.10 4.25 0.06 88.00 pm – Oct 7 @ 1:20 am
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Event Date Start – End of Rainfall Storm Rainfall Ante- Event Depth Duration Intensity cedent (in) (hrs) (in/hr) Dry Period (hrs) 48 Oct 11 – 12 Oct 11 @ 10:15 0.42 7.83 0.11 116.92 pm – Oct 12 @ 6:05 am 49 Oct 16 – 17 Oct 16 @ 5:20 1.11 21.33 0.22 95.25 am – Oct 17 @ 3:00 am 50 Oct 21 -22 Oct 21 @ 10:50 0.13 14.42 0.05 115.83 pm – Oct 22 @ 1:15 pm 51 Oct 26 – 27 Oct 26 @ 11:55 0.78 20.58 0.13 94.67 am – Oct 27 @ 8:30 am 52 Oct 30 – Nov Oct 30 @ 2:10 1.83 49.33 0.21 77.67 1 pm – Nov 1 @ 3:30 pm 53 November 7 4:05 am – 1:45 0.21 9.67 0.06 132.58 pm 54 Nov 11 – 12 Nov 11 @ 12:50 0.75 13.83 0.13 95.08 pm – Nov 12 @ 2:40 pm 55 November 27 2:10 am – 9:55 0.17 7.75 0.09 347.50 am 56 December 1 5:25 am – 5:50 0.82 12.42 0.29 91.50 pm 57 Dec 2 – 3 Dec 2 @ 6:55 am 0.24 22.00 0.08 13.08 – Dec 3 @ 4:55 am 58 December 4 10:50 am – 9:55 0.13 11.08 0.06 17.92 pm 59 December 9 8:15 am – 9:35 0.55 13.33 0.10 106.33 pm 60 Dec 14 – 15 Dec 14 @ 6:10 0.49 19.50 0.09 104.58 am – Dec 15 @ 1:40 am 61 Dec 29 - 31 Dec 29 @ 5:45 0.70 55.17 0.13 340.08 am – Dec 31 @ 12:55 pm 62 January 3 – 5 Jan 3 @ 6:55 am 0.50 43.25 0.06 66.00 – Jan 5 @ 2:10 am
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Event Date Start – End of Rainfall Storm Rainfall Ante- Event Depth Duration Intensity cedent (in) (hrs) (in/hr) Dry Period (hrs) 63 Jan 10 – 12 Jan 10 @ 12:25 1.32 41.17 0.13 118.25 am – Jan 12 @ 5:35 am 64 Jan 18 – 19 Jan 18 @ 2:00 0.78 25.17 0.19 140.42 am – Jan 19 @ 3:10 am 65 Jan 24 - 26 Jan 24 @9:25 0.58 39.50 0.12 126.25 am – Jan 26 @ 12:55 am 66 February 5 8:00 pm – 11:05 0.24 3.08 0.12 259.08 pm 67 February 6 – 7 Feb 6 @ 11:05 0.36 28.92 0.13 12.00 am – Feb 7 @ 4:00 pm 68 Feb 9 – 10 Feb 9 @ 5:50 0.34 21.08 0.09 49.83 pm – Feb 10 @ 8:55 am 69 Feb 12 – 13 Feb 12 @ 8:00 0.37 23.25 0.08 59.08 pm – Feb 13 @ 7:15 pm 70 Feb 17 – 18 Feb 17 @ 11:40 0.27 7.00 0.07 100.42 pm – Feb 18 @ 6:40 am 71 Feb 24 – 25 Feb 24 @ 9:00 0.15 3.92 0.06 158.33 pm – Feb 25 @ 12:55 am
Table 3.2 summarizes the average duration and depth of the 71 storms listed in
Table 3.1. The US EPA collected annual storm event statistics for 15 rain zones throughout the United States using NOAA precipitation data. The historical data
(created about 30 years ago) is compared to the 2019-2020 rain events in Table 3.3. The
2019-2020 monitoring period has higher rainfall statistics than the historical data. There are more storms that are longer, carry more volume, and have stronger intensity.
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Table 3.2 Summary of Rainfall Duration and Depth for 2019-2020 Monitoring Period Event Type Duration (hrs) Depth (in) Average Event 15 0.66 50% average event 7.5 0.33 150% average event 22.5 0.99
Table 3.3. Comparison of 2019-2020 Monitoring Period to Historical Data Annual Statistics Independent Storm Event Statistics No. of Precipitation Avg Avg Avg Storms (in) Duration Intensity Depth (hr) (in/hr) (in) Historical NOAA Data 55 34.6 9.5 0.087 0.55 2019 – 2020 Monitoring 71 46.8 15 0.26 0.66 Period
Overall, the rain events used to collect wet weather samples across the watershed seem representative. Figure 3.1 compares rainfall depth and storm duration for all 71 rain events. The eleven wet weather collections are delineated, highlighted in red.
Rainfall depth and duration for the eleven collections fell within 50% - 150% of the average depth except for June, which was a particularly wet month, and the last wet weather collection in January. The October 30th storm was sampled at the onset of the storm to obtain urban run-off nutrient concentrations, so duration and depth were not influential. Figure 3.2 shows the antecedent dry period for each event and rainfall intensity. Events are shown relative to the minimum desired 72 hours preceding a wet weather collection and the average 0.26 inches/hour storm event. All summer storms sampled met or exceeded the average rainfall intensity with the exception of the July 30th collection (0.22 in/hr). Three of the sampled events had antecedent dry periods less than
72 hours which may impact results.
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Figure 3.1. Summary of 2019-2020 Rainfall Events: Depth and Duration
Figure 3.2. Summary of 2019-2020 Rainfall Events: Antecedent and Rainfall Intensity
23
The NEORSD Beachwood Rain Gauge began reporting data for the public on
February 28, 2012 (NEORSD, 2020). Average annual rainfall for this 8-year period was about 45 inches. In terms of annual rainfall, the monitoring period seems representative at 49 inches (March 2019 – March 2020). Table 3.4 shows the NEORSD Beachwood
Rain Gauge Data from 2012 until March 2020.
Table 3.4. NEORSD Beachwood Rain Gauge Data (2012-2020) 2012 2013 2014 2015 2016 2017 2018 2019 2020 Rainfall (in) January 1.92 1.09 2.18 1.00 5.92 2.86 3.26 3.53 February 1.53 1.79 1.60 2.65 3.46 3.62 2.44 2.37 March 3.42 2.15 1.67 1.52 4.00 5.22 4.66 3.18 6.68 April 1.83 3.41 5.91 3.31 3.22 5.78 5.06 4.55 3.95 May 1.19 3.67 3.02 4.75 2.95 7.90 4.24 4.75 5.44 June 1.40 3.65 6.41 9.45 0.79 5.30 4.19 10.47 July 3.16 6.78 7.05 3.34 2.92 3.07 3.98 3.36 August 2.93 2.55 4.66 1.83 2.83 6.08 3.72 3.83 September 8.18 3.37 4.99 2.93 3.04 1.49 5.52 4.26 October 12.16 5.94 5.27 2.61 4.31 4.00 5.11 4.16 November 1.13 3.63 3.21 2.13 3.16 6.81 5.21 1.88 December 4.78 3.29 2.14 2.82 2.47 1.50 2.95 3.05 TOTAL 41.89 47.21 38.47 33.34 56.53 51.12 49.19
In terms of a monthly comparison, 2019 was representative of recent years. June stands out as a wetter than normal month, but monthly precipitation of 10 inches does occur. Although unusual, both October 2012 and June 2015 posted similar volumes of rainfall as was shown in Table 3.4. Table 3.5 displays monthly statistics for the monitoring period. September 2019 was unusual in that it had a stronger rainfall intensity and higher average storm depth than recent years. Overall, September and
November had the least number of rain events. There was a strong storm recorded on
September 13th, which was preceded by another significant storm (See events 44 and 45 on Table 3.1).
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Table 3.5. Monthly Rainfall Characteristics for the 2019-2020 Monitoring Period 2012-2020 Avg Avg Avg Avg Ant Number Total Beachwood Month Depth Duration Intensity Dry of Depth Average (in) (hrs) (in/hr) Period Rain (in) Total (hrs) Events Depth (in) Mar 0.59 13.57 0.17 170 5 3.18 3.61 Apr 0.61 13.77 0.18 89 7 4.55 4.11 May 0.50 12.81 0.22 68 9 4.75 4.21 Jun 1.30 14.59 0.54 66 8 10.47 5.21 Jul 0.46 8.60 0.29 103 7 3.36 4.21 Aug 0.62 5.54 0.43 104 6 3.83 3.55 Sept 1.36 13.11 0.94 125 3 4.26 4.22 Oct 0.67 18.84 0.13 145 7 4.16 5.45 Nov 0.38 10.42 0.09 192 3 1.88 3.40 Dec 0.49 22.25 0.13 112 6 3.05 2.88 Jan 0.80 37.27 0.13 113 4 3.53 2.72 Feb 0.29 14.54 0.09 106 6 2.37 2.43 AVG 0.67 15.44 0.28 116 6 4.12 3.83 TOTAL 71 49.39 45.39
3.2 Water Quality Monitoring & Assessment Reporting
Biennially, each state is required to submit a list (i.e., 303(d) list) of all impaired and threatened streams and lakes located within its borders to the US EPA, as required by the federal Clean Water Act (US EPA, 2020i). The law requires states to rank and develop TMDLs for these impaired waters (USEPA Office of Water, 2009). A TMDL is the maximum pollution tolerance a water body can tolerate while still meeting water quality standards (US EPA, 2020j). States submit long-term plans to reduce pollution loads for these surface waters and the US EPA assembles these individual state lists into one national tracking system (US EPA Office of Water, 2009).
25
This collaboration is called the EPA’s Assessment and TMDLs Tracking and
Implementation System (ATTAINS). According to the US EPA’s Office of Water, there are different reasons for stream impairment. Nutrients are responsible for approximately
10 percent of all reported impairments. Figure 3.3 displays the top 15 causes cited by the
US EPA. Causes shown on Figure 3.3 that account for no more than 5 percent of all impairments are (in descending order): polychlorinated biphenyls (PCBs), unknown impaired biota, turbidity, temperature, pesticides, salinity, unknown causes, and noxious aquatic plants. The top five sources account for the majority (58%) of all surface water impairments.
2% 2% 2% 5% 2% 15% 5% Pathogens (15%)
5% Mercury (12%) 12% Other Metals (11%) 5% Nutrients (10%)
Sediment (10%) 6% 11% 9% Organic Enrichment (9%)
10% pH (6%) 10%
Figure 3.3. Impairment Causes for US Waters Source: US EPA Office of Water, 2009
In 2018, the Ohio EPA reported stream assessments (biological and chemical data) on a total of 1,538 watershed units (Ohio EPA, 2018). Streams were assessed on four major uses: human health, recreation, aquatic life, and public drinking water
26 supplies. Human health impairment was based on the evaluation of fish tissue contamination. Recreation attainment was based on the number of bacteria in the water.
Ohio used surveys of fish and aquatic insects to assess aquatic life. Public drinking water supplies focused on testing of nitrate, pesticides, and cyanotoxins (Ohio EPA, 2018).
Ohio set a 2020 goal of 80 percent attainment of aquatic life for all its wading and principal streams and rivers (Ohio EPA, 2018). The overall trend since 2010, the baseline year, has been positive, increasing by almost 8 percent as shown in Figure 3.4.
Figure 3.4. Aquatic Life Attainment for Ohio’s Wading & Principal Streams Source: Ohio EPA, 2018
Euclid Creek was listed as impaired for aquatic life. Both the East and Main
Branch are in non-attainment status. The causes were listed as flow regime modification, pollutants in urban stormwater, habitat alterations, and unknown. The sources listed were channelization, municipal urbanized high-density area, contaminated sediment resuspension, unknown sources and urban run-off caused by wet weather storm sewers
27 and CSO activations. Fish were found to be more impacted than macroinvertebrates
(Euclid Creek Watershed Program, 2018). Overall, the upper watershed suffered from urban land use development and loss of riparian vegetation while hydromodification compromised the lower watershed (Euclid Creek Watershed Program, 2018).
Euclid Creek was also listed as impaired for recreation use, although this outcome relied on historical data. Attainment for human health was unknown and it is not currently used for public drinking water (Ohio EPA, 2018). The Ohio EPA submitted a priority ranking list for all 1536 reported watersheds. The highest priority areas were given the most points. The scale ranged from a minimum priority of zero to the highest priority of seventeen. Euclid Creek ranked in the 80th percentile with 5 priority points.
The state distribution was heavily right skewed with a median of 2 points. A histogram of the data is shown in Figure 3.5.
Figure 3.5. Priority Ranking of Ohio Watersheds Source: Ohio EPA, 2018
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Sampling is an important strategic method to identify water quality problems in the watershed (Cuyahoga Soil & Water Conservation District, 2020). Water chemistry data has been collected by the Ohio EPA and The Northeast Ohio Regional Sewer
District (NEORSD) annually since 1989. The Euclid Creek TMDL used sampling conducted by Ohio EPA, NEORSD, Cuyahoga County Board of Health, and John Carroll
University (Euclid Creek Watershed Program, 2018).
Recent sampling by NEORSD and The Euclid Creek Watershed Program was reviewed for this thesis. NEORSD’s water quality data was conducted by its
Environmental Assessment Group in the Water Quality and Industrial Surveillance
Division (WQIS). WQIS are Level 3 Qualified Data Collectors certified by the Ohio EPA.
The Euclid Creek Watershed Monitoring Program began in 2005 and was conducted by trained volunteers.
3.3 NEORSD Sampling
Since 2006, WQIS has collected water quality data on Euclid Creek and its tributaries. The number of sites and sample size have varied each year. NEORSD recommends an annual monitoring plan that is subject to approval from the Ohio EPA.
The most recent water quality data publicly available was collected in 2018, downstream of the confluence of the two branches. Three sites were investigated at River Miles
(RMs) 0.40, 0.55 and 1.65, which were labeled according to their respective distance from the mouth of Euclid Creek. The sites were monitored to collect post restoration water chemistry data and for NPDES permit regulations (NEORSD, 2019a). Stream restoration and sewer infrastructure projects were completed before and during the
29 collection period (NEORSD, 2019a). The NEORSD projects involved interceptor tunnels designed to reduce CSO activations from 60 to two events per year and have been in service since July 2018. The 2012 – 2013 restoration project goal was to improve the downstream ecology of Euclid Creek (NEORSD, 2019a). NEORSD’s Analytical Services
Division analyzed water samples from the three sites for total phosphorus, DRP, nitrite, nitrate nitrite, ammonia, alkalinity, turbidity and suspended solids. Collection techniques followed procedures outlined in the Surface Water Field Sampling Manual
(Ohio EPA, 2015). WQIS collected water samples at each site on five occasions. Field measurements were also taken for dissolved oxygen, pH, temperature, conductivity and turbidity (NEORSD, 2019a). WQIS monitoring resulted in relatively low nutrient levels as shown in Table 3.6.
Table 3.6. 2018 NEORSD Nutrient Results for Euclid Creek River Sample Date Total DRP Dissolved Mile Phosphorus (mg/L) Inorganic (mg/L) Nitrogen (mg/L) 6/19/2018 0.087 0.039 0.636 6/26/2019 0.037 0.022 0.322 0.40 7/2/2019 0.081 0.023 0.139 7/10/2019 0.038 0.022 0.314 7/17/2019 0.072 0.031 0.542 GeoMean 0.059 0.027 0.344 6/19/2018 0.079 0.044 0.587 6/26/2019 0.04 0.028 0.294 0.55 7/2/2019 0.032 0.018 0.263 7/10/2019 0.037 0.025 0.270 7/17/2019 0.067 0.032 0.500 GeoMean 6/19/2018 0.0695 0.04 0.632 6/26/2019 0.04 0.03 0.431 1.65 7/2/2019 0.044 0.026 0.400 7/10/2019 0.038 0.028 0.458 7/17/2019 0.068 0.036 0.476 GeoMean 0.050 0.032 0.473 Source: NEORSD, 2019b
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3.4 The Euclid Creek Watershed Program
The Euclid Creek Volunteer Monitoring Program (ECVMP) aimed to collect water chemistry data on a monthly basis at seven sites. The sites were located throughout the watershed and are detailed in Section 4.2. The purpose of the monitoring data was for public awareness and education (Cuyahoga Soil & Water Conservation
District, 2020). Any critical observations were reported to the Ohio EPA. ECVMP collectors conducted on-site analyses for turbidity, ammonia, reactive phosphate, dissolved oxygen, temperature, conductivity, total dissolved solids, salinity and pH.
Typically, ECVMP volunteers select one site to collect data at monthly. The monitoring program began in 2006 with five original sites. A sixth site was added in 2011 and the seventh in 2016. Weather and water level conditions were noted during collections. Historically, the water sampling collected by ECVMP volunteers was comparable to the data collected for the Euclid Creek TMDL (Cuyahoga Soil & Water
Conservation District, 2020).
Figure 3.6 summarizes the reactive phosphate levels from collections spanning from 2006 to 2019 for each site. Target levels were exceeded at all sites at least 75 percent of the time. Unlike phosphorus, ammonia levels (chosen to represent nitrogen), were consistently below target levels. Phosphorus levels throughout the watershed have remained above the target and continue to be problematic.
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Figure 3.6. Euclid Creek Volunteer Phosphorus Monitoring Data (2006-2019) Source: Euclid Creek Watershed Program, 2020
3.5 Historical Rainfall Data Exploration
Historical rainfall patterns were explored using NOAA’s National Centers for
Environmental Information website and the NEORSD’s Rainfall Dashboard website.
Daily precipitation summaries were compiled from 1939 to the present for the Cleveland
(CLE) Hopkins Airport, the closest NOAA rain gauge to the monitoring site. Five- minute interval rainfall summaries were compiled from 2012 to the present for the
Beachwood Rain Gauge (RBH), the closest NEORSD rain gauge to the monitoring site.
The Euclid Creek Watershed and the Cleveland Hopkins Airport are approximately 20 miles apart. Figure 3.7 highlights the Airport’s Watershed location in yellow and the
Euclid Creek Watershed in red. The NEORSD’s rain gauges are shown in blue. The
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Beachwood Rain Gauge (RBH) which was used for this study, is shown at the upstream portion of the Euclid Creek Watershed.
Figure 3.7. NOAA and NEORSD Rain Gauge Locations Sources: NOAA, 2020; NEORSD, 2020
Daily precipitation values were compared for the two rain gauges from 2012 to
2019. Results of a matched-pairs t-test shown in Table 3.7 show that there was a significant difference [ p < 0.05 ] between the two gauges. On average, the daily precipitation difference was 0.06 inches.
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Table 3.7. Summary Statistics for Matched-Pairs t-test Between Rain Gauges (2012-2019) Beachwood – CLE Hopkins Airport Rain Gauge Statistical Measure Mean of Daily Precipitation 0.06 inches (Absolute Value of Differences) Standard Deviation of Daily Precipitation 0.17 inches (Absolute Value of Differences) Number of Days Compared 2863 t 18.9 P-value < 0.00001
When looking at monthly trends for these same years, at least two months each year differed by more than one inch. Table 3.8 shows monthly differences between the rain gauges for the 94 consecutive months. Most importantly, there was substantial variation during the summer and early fall, when most of the sampling occurred. During these months (May – October), over half exceeded differences of at least one inch of rainfall. On average, the monthly precipitation difference was 0.89 inches. [t=10.03, p<0.00001].
Table 3.8. Difference in Monthly Rain Gauge Totals (Beachwood – CLE Airport) 2012 2013 2014 2015 2016 2017 2018 2019 January -0.25 -0.91 -0.76 -0.37 1.14 0.59 0.08 February -0.77 -1.24 -0.26 -0.57 0.78 0.37 -0.04 March -0.46 -0.10 -0.53 -0.45 -0.17 1.20 0.65 0.09 April -0.14 -0.09 0.95 0.54 -0.64 1.29 0.68 0.54 May -0.25 1.30 -1.06 0.66 -0.36 1.81 -1.48 0.61 June -0.64 -4.25 0.15 0.93 -1.33 -0.55 0.36 2.39 July -1.16 1.87 3.06 0.62 1.10 0.60 -2.70 0.74 August 0.08 -0.26 0.07 -1.02 -0.67 4.83 -1.17 0.60 September 0.62 1.41 0.52 -1.98 -2.34 0.68 1.18 2.98 October 1.76 1.24 2.43 0.44 1.35 0.32 1.33 0.84 November 0.37 0.75 -0.47 -0.18 1.05 0.86 -0.26 0.18 December 0.85 -0.81 0.19 -0.14 -0.18 -0.23 0.10 0.20
Although the rain gauges recorded different amounts from 2012 to 2019, the monthly 2019 Beachwood precipitation was compared to the historical Cleveland data
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(1939-2019) to obtain a sense of historical trends for the area prior to 2012. The monthly precipitation amounts this year in Beachwood seem typical when compared to past monthly Cleveland area weather trends, except for June. As Figure 3.8 shows, only two months since 1939 accumulated more than 10 inches of precipitation in the Cleveland area, September 1996 (11.05 inches) and October 2012 (10.40 inches). Like the historical
CLE data, the Beachwood Rain Gauge recorded two months exceeding ten inches of rainfall (See Figure 3.9).
Figure 3.8. Historical Monthly Trends at Cleveland Hopkins Airport (1939-2019) Source: NOAA, 2020
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Figure 3.9. Beachwood Rain Gauge Monthly Rainfall Totals (2012 – 2019) Source: NEORSD, 2020
Historical data points to a plausible increase in precipitation. Both data from
Cleveland Airport and all NEORSD rain gauges show a slightly positive trend. Figure
3.10 shows annual precipitation amounts for the CLE Airport at about 0.46 inches of additional rain per year (r = 0.21) and annual mean precipitation amounts for the 26
NEORSD rain gauges at about 1.57 inches of additional rain per year (r = 0.65).
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Figure 3.10. Annual Means at Cleveland Hopkins Airport and Mean of all NEORSD Rain Gauge Data (2013-2019) Sources: NOAA, 2020; NEORSD, 2020
The strongest rainfall event during the monitoring period fell on September 13,
2019. This storm had a rainfall depth of 2.42 inches over the course of 4.17 hours. The rainfall intensity was 2.12 inches/hour. In comparison to historical data, daily rainfall exceeded two inches at the Cleveland Hopkins Airport 53 times since 1939. In summary, the 2019-2020 monitoring period seems representative of rainfall in the area, noting that
June 2019 was an excessively wet month.
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CHAPTER 4
EXPERIMENTAL METHODS
4.1 Overview of Site Selection Process
Sites were visited in the same order, upstream to downstream, throughout the monitoring period. During each site visit, observations were recorded, field measurements were taken, water samples were collected for subsequent lab analysis, and statistics of these samples were later compiled and calculated.
The first site visited for each collection was Acacia, the furthest upstream,
“headwaters” of the Main Branch. The next two sites, in order, were Telling Mansion and
Schaefer Park. After mid-summer investigations, four upstream tributary locations were added and sampled next in the order of: Spencer Road, Harris Road, Community Center, and U/S Stonewater. Collections then proceeded to the East Branch. The most upstream location for the East Branch, Rockefeller Road, was sampled next. Following this site were Bishop Road and Richmond White. The next site visited was the confluence of the two branches. Independent samples were taken immediately prior to the mixing of the branches, at Highland East and Highland Main. Downstream samples were taken last at
Villaview and Wildwood.
Field samples at each site were taken at the same location unless conditions were unsafe or difficult due to summer low flow. Samples were typically taken midstream,
38 using a bucket dropped from the center of a bridge for all locations except the Highland
Site. Here, samples were taken by wading out to the middle of the stream. During a few extreme wet weather events, samples were drawn from the embankment.
Sampling began in March 2019 with nine sites: the seven volunteer monitoring sites used for the 2019 Euclid Creek Watershed Monitoring Program, and two additional sites in the upper reaches of the East Branch. The initial seven volunteer monitoring sites were Acacia, Telling Mansion, Schafer Park, Richmond White, Highland East, Highland
Main and Wildwood. The two additional East Branch upstream locations were
Rockefeller Road and Bishop Road. Due to the influence of Lake Erie, a sampling location upstream of the Wildwood location was established on July 13, 2019. Based on the elevated nutrient levels at the Schaefer Park location, an investigation was conducted on
July 31, 2019 along the tributary incorporating Schaefer Park. As a result, sampling at the
Spencer Road site began on August 6, 2019. The differences in nutrient levels between the East and Main Branches led to an investigation that was carried out upstream of the
Richmond White site on August 29, 2019. The last three sites, Harris Road, Community
Center and U/S Stonewater were added on September 4, 2019.
Sites are discussed in order of collection, from upstream to downstream. Each sampling event was completed in a day, within an approximate 5-hour timeframe. The fourteen site locations are shown below on Figure 4.1.
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Figure 4.1. Sampling sites used to assess water quality in Euclid Creek Watershed
4.2 Sampling Site Descriptions
4.2.1 Acacia
The Acacia site is the furthest upstream location in the Main Branch of Euclid
Creek. The Conservation Fund sold the 155-acre former golf course to the Cleveland
Metroparks in 2012 for $14 million (Ewinger, 2013). Future use of the site is heavily restricted, as it is intended to become a fully forested nature preserve.
The restoration project doubled the size of public park land within the watershed. There are nine other public parks in the watershed with a combined area of
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141 acres (Ewinger, 2016). These 10 parks account for 2% of the total land use within the watershed. The Donald Ross-designed golf course had extensive underground drain tiles which transferred water off-site as quickly as possible. The Metroparks planted over
6,000 trees and restored Euclid Creek to its natural banks (Frolik, 2018).
Richmond Road and Cedar Road, both heavily used 4-lane carriageways, border
Acacia on the west and south sides, respectively. Condominiums and single-family homes border the park on its remaining sides. Immediately upstream of Acacia is the
Beachwood Place shopping mall. The mall has 137 stores and services totaling almost 1 million square feet of retail area. There are over 4,200 parking spaces (Beachwoodplace,
2019). The impervious surface area for this parking may be a pollution source during wet weather events.
The sampling site was located at the bridge as the creek enters the park, at Cedar
Road. Figure 4.2a shows a downstream view of the creek from the eastern approach to the bridge. Samples were taken on the downstream side, at the center of the bridge.
There were multiple storm sewers at this location. Two sewers were set parallel to the stream channel and the remaining sewers ran perpendicular to the stream channel. As
Figure 4.2b shows, the parallel storm sewers were culverted in separate channels adjacent to the stream, one on each side. The smaller perpendicular storm pipes were located on the downstream right side of the stream, as seen in Figure 4.3.
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Figure 4.2 Acacia Site Views: (a) looking downstream from pedestrian bridge and (b) looking at sampling site from downstream location
Figure 4.3 Storm drains at Acacia on Eastern Embankment
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4.2.2 Telling Mansion
The second monitoring site was Telling Mansion, located where the creek crosses
Mayfield Road. Mayfield Road is another busy, 4-lane carriageway. This site is named for the adjacent property, the Telling Mansion Museum of American Porcelain Art. Between
Acacia and the Telling Mansion sites, the creek passes The Legacy Village. This mall, opened in 2003, consists of about 50 stores, a 135-room Hyatt Hotel, and a 355-space parking garage (Jarboe, 2015). In addition to The Legacy Village, the creek passes by two schools, The Hawken Lower School and the Julie Billiart School, and a private 36-hole golf club, The Mayfield Sand Ridge Club.
The sampling site was located at the pedestrian bridge along Mayfield Road.
Samples were taken on the downstream side, at the center of the bridge. Figure 4.4a shows the downstream view of the creek from the sampling bridge site. There was a storm sewer located parallel to the creek. Looking upstream, as in Figure 4.4b, the storm sewer is to the right of the creek. During the summer, there was a distinct orange colored water area downstream approximately 30 feet from the storm sewer. Figure 4.5 shows this stagnant, discolored water area.
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Figure 4.4. Telling Mansion Site Views: (a) looking downstream from pedestrian bridge and (b) looking at sampling site from downstream location
Figure 4.5. Possible iron deposit area downstream of Telling Mansion Site
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4.2.3 Schaefer Park
The third site was located along an unnamed tributary of the Main Branch that connects downstream of Telling Mansion. This is the major tributary to the Main
Branch. The headwaters of this creek begin at Lyndhurst Park, immediately downstream of the Lyndhurst Municipal Court. This tributary creek meanders through residential homes and a second park (Roland Park) until it reaches Schaefer Park. The three town parks, Schaefer Park, Roland Park and Lyndhurst Park, are all smaller town parks, each about 10 acres of green space. Both Schaefer Park and Roland Park contain two baseball fields apiece and general green space. Lyndhurst Park has a community pool, four tennis courts, a community center, and additional green space. The approximate length of the tributary is one mile. As Figure 4.6 shows, Roland Park lies approximately halfway between Lyndhurst and Schaefer Parks.
Figure 4.6. Land use surrounding unnamed tributary to Main Branch
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The sampling site was located at the pedestrian bridge between Edenwood Road and Ridgebury Boulevard. Samples were taken on the downstream side, at the center of the bridge. Figure 4.7a is a view of the sampling bridge site and the large storm sewer located on the left embankment looking downstream from the bridge site. There were two storm sewers located at this site, one on each side of the stream. Figure 4.7b shows the second storm sewer (located on the right embankment looking downstream from site).
Figure 4.7. Schaefer Park Site Views: (a) looking at sampling site from downstream location and adjacent storm sewer and (b) second storm sewer on downstream opposite embankment
4.2.4 Spencer Road
On July 31, an investigation was carried out upstream of Schaefer Park. Schaefer
Park nutrient levels were consistently the highest in the watershed throughout June
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2019. The goal of the investigation was to sample throughout the entire tributary to determine if other areas along this creek yielded similar results. Six sampling locations were selected as shown on Figure 4.8: (1) Spencer Road, (2) Edenhurst Road, (3) Roland
Park, (4) Roland Park Storm Sewer, (5) Ridgebury Road, and (6) Schaefer Park. As a result of this investigation, the site at Spencer Road was added as another location due to high nutrient concentrations at the headwater of this tributary. (See Section 5.4 for results of the investigation.)
Figure 4.8. Schaefer Park Investigation Locations
Spencer Road is the upstream location of the Schaefer Park tributary. It is located in between Alvey Road and Roland Road. The closest residence is 5216 Spencer Road.
The location is downstream of Lyndhurst Park, in a residential area. Samples were taken on the downstream side of the stream, at the center of the stream, immediately after
47 being culverted under Spencer Road. Figure 4.9 shows the downstream view of the stream from the sampling site.
Figure 4.9. Downstream View at Spencer Road Site
4.2.5 Harris Road
On August 29th, an investigation was carried out upstream of Richmond White.
There are multiple tributaries that deposit their water into the East Branch. Eight sites were selected to gain further insight on upstream conditions as shown on Figure 4.10.
Sites sampled on August 29th were: (1) Rockefeller Road, (2) Bishop Road, (3) Golf View
Drive, (4) Route 175 (downstream of Cuyahoga County Airport), (5) Community Center on Highland Road, (6) Richmond White, (7) Downstream of Bishop Road (on White
Road), and (8) Downstream of Rockefeller Road (on Bishop Road). As a result of this investigation, three additional sites were monitored: Harris Road, Community Center and U/S Stonewater (See Section 5.4 for results of the investigation.).
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Figure 4.10. East Branch Investigation Sample Locations
The Harris Road sampling site was located on Harris Road, where the tributary crosses the road, just south of the intersection with Highland Road. The stream is culverted under the residential road. Samples were taken at the middle of the stream, on the upstream side. This site monitored upstream conditions for
Redstone Run, a tributary to the East
Branch. Figure 4.11 shows the upstream view of the tributary from the sampling bridge location.
Figure 4.11. Harris Road Site Looking Upstream
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4.2.6 Community Center
This site was located along Highland Road, at the Richmond Heights
Community Park. This small, 9-acre park is located east of the intersection of Richmond
Road and Highland Road. The park has three baseball fields, four tennis courts and a pool. This location was used to monitor upstream conditions of Claribel Creek, a tributary to the East Branch.
Samples were taken in the creek, immediately downstream of Park Avenue, at the entrance to the Community Park. Highland Road is a busy 2-lane thoroughfare for local traffic. Upstream of this sampling location, the stream travels through residential areas.
Figure 4.12 shows the upstream view of the creek at the entrance of the Community
Park. There was one storm sewer located at the sampling location as shown in Figure 4.13a. The storm sewer is located on the left side of the creek looking upstream. There was an additional storm sewer pipe draining into the creek visible further downstream from the sampling site.
Figure 4.13b shows this storm sewer pipe, located on the right side of the creek looking downstream.
Figure 4.12. Community Center Site looking upstream
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Figure 4.13. Community Center Site Views: (a) looking at storm sewer at site and (b) looking at second storm sewer downstream of site
4.2.7 U/S Stonewater
This site was located along Highland Road, east of the intersection of Bishop
Road and Highland Road. This site was located at the upstream reaches of another tributary to the East Branch. Samples were taken on the upstream side of the stream, at the center of the stream. Samples were taken at the center of the roadway bridge, immediately prior to the culverted stream section on Highland Road. The land use upstream of the sampling location is largely residential homes. Downstream of the sampling location, the stream crosses Highland Road, traversing parallel and east of
Bishop Road. It travels through StoneWater Golf Club and under the Cuyahoga County
Airport. It then passes under White Road, where it joins the East Branch. Figure 4.14a shows an upstream view of this tributary from the center of the bridge. Looking
51 upstream, the left embankment has natural vegetation while the right embankment is supported by a double layer of gabion baskets. Two smaller storm sewer pipes are located within the gabion baskets and are visible in the background of Figure 4.14a.
These two pipes were located upstream of the sampling site. Figure 4.14b shows another storm sewer that is located at the base of the gabion baskets, a few feet upstream of the sampling location.
Figure 4.14. U/S Stonewater Site Views: (a) looking upstream from sampling site with storm drains further upstream and (b) looking upstream from site with storm sewer at sampling site
4.2.8 Rockefeller Road
This site was the furthest upstream sampling location along the East Branch of
Euclid Creek. Rockefeller Road parallels I-271, connecting White and Chardon Roads. It
52 is a 2-lane carriageway in a predominantly residential area. There is one school located upstream, the Willoughby-Eastlake School of Innovation.
The sampling site was located along the east shoulder of Rockefeller Road, just south of a residential home located at 2901 Rockefeller Road. Samples were taken on the upstream side of the stream, at the center of the bridge above the stream. The stream was culverted under the roadway. Figure 4.15 shows the upstream view of the East Branch.
On the left embankment, there is a storm sewer draining into the creek immediately upstream of the sampling location.
Figure 4.15. Upstream view of Rockefeller Road Site
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4.2.9 Bishop Road
This site is directly downstream of the Airport Greens Golf Course. This small tributary drains an interior pond of the golf course, northeast of the Cuyahoga County
Airport. The tributary runs under Bishop Road, the location site for sampling. The tributary is east of Bishop Road, while the airport is west of Bishop Road. This location was selected to monitor any potential water quality impacts associated with the golf course.
The sampling site was located on the east shoulder of Bishop Road, just south of the intersection of White Road and Bishop Road. Bishop Road is a busy 2-lane carriageway. Samples were initially taken on the downstream side of the stream; however, the stream level was very low at this location during the early summer, making it difficult to sample. Starting in July 2019, sampling was continued at the same roadway location, but on the opposite (west) shoulder of Bishop Road. Samples were taken on the upstream side of the stream, at the center of the roadway bridge. Figure 4.16a shows the upstream view of the tributary as seen from the sampling site bridge. There is a storm sewer draining into the stream under the bridge abutment. Figure 4.16b shows this storm sewer. The photo was taken on the downstream side of the bridge, looking at the right abutment when facing upstream.
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Figure 4.16. Bishop Road Site Views: (a) upstream view of tributary and (b) storm sewer at sampling site, downstream side of bridge
4.2.10. Richmond White
This site was downstream of the confluence of the Bishop Road tributary with the East Branch. The site is located on Richmond Road, at the intersection of Richmond and White Roads. Richmond Road is another busy 2-lane thoroughfare. Land use surrounding the site was a mixture of businesses and residential homes. This location was downstream of the Cuyahoga County Airport.
The sampling site was located at the pedestrian bridge along the east side of
Richmond Road. Samples were taken on the upstream side, at the center of the bridge.
Figure 4.17a shows the upstream view of the East Branch. On occasion, due to inclement weather or low flow conditions, samples were taken directly in the stream, upstream of the sampling site. These samples were accessed by climbing down the embankment
55 located alongside White Road. Figure 4.17b was taken at this location, looking downstream at the routine bridge sampling site.
Figure 4.17. Richmond White Site Views: (a) upstream of East Branch at sampling site and (b) looking downstream at the sampling site from upstream location
4.2.11. Highland Main
The East Branch of Euclid Creek converges with the Main Branch approximately
3 miles downstream of the Richmond White site. The confluence of the two branches occurs at the Highland Picnic area, within the Euclid Creek Reservation. This picnic area is located close to the intersection of Highland Road and Euclid Creek Parkway. The 3- mile stretch of the East Branch between Richmond White and the confluence of the branches is in a predominantly residential area. The East Branch loosely parallels Route
6, Chardon Road.
Unlike the residential land use of the East Branch, the Main Branch lies within the protected natural setting of the Cleveland Metropark. The Main Branch of Euclid
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Creek parallels Euclid Creek Parkway until the Parkway terminates at the southern entrance of the Euclid Creek Reservation, at the intersection of East Green Road and
Euclid Creek Parkway. The Main Branch is protected for about 2.5 miles upstream of the stream confluence location. The park has wooded, canopied recreational trails. The Main
Branch meanders through the park, which is full of lush vegetation and steep hillsides.
Samples were taken directly in the stream, along the left embankment (looking upstream), just upstream of the confluence of the East and Main Branches. Access to the site was through the park, past the basketball courts and bridge. Figure 4.18a shows a downstream view of the Main Branch. The photo was taken on the bridge, looking at the confluence of the two branches. Figure 4.18b was taken at the approximate sampling site, looking upstream at the bridge.
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Figure 4.18. Highland Main Site Views: (a) looking at sampling site and (b) looking upstream from sampling site
4.2.12. Highland East
This sampling site was adjacent to the Highland Main sampling site, in the interior of the Euclid Creek Reservation, near the intersection of Highland Road and
Euclid Creek Boulevard. Samples were taken in the middle of the stream, just upstream of the confluence of the streams. During inclement weather, care was taken to obtain independent samples as close to the site as possible.
Highland Road was closed due to construction during much of the monitoring period. Figure 4.19a shows construction equipment in the Main Branch, downstream of the confluence of the two branches. Ten years ago, a small dam was removed under this high bridge at Highland Road. The 6-foot high, 40-foot wide concrete dam was originally constructed to pond water for wading at a YMCA camp (Scott, 2010). After 77 years,
58 construction commenced in order to improve water quality issues like downstream flooding, erosion, sediment build-up and better fish migration (Scott, 2010). Figure 4.19b shows the upstream view of the East Branch.
Figure 4.19. Highland East Site Views: (a) downstream view of the confluence of the two branches and (b) looking upstream from site
4.2.13. Villaview
Collection began at this location on July 13, 2019. Due to Lake Erie’s record- setting mean monthly water levels, the direction of water flow was questionable at the
Wildwood sampling location, the most downstream sampling location. Beginning in
May 2019, the Great Lakes recorded 100-year water level records (Army Corps of
Engineers, 2020). High lake levels continued throughout the monitoring period, and into
2020. Thus, the Villaview site provided additional water chemistry testing downstream of the confluence of the two branches.
Euclid Creek is culverted under I-90 and is daylighted at Villaview Road.
Villaview Road is a busy 4-lane thoroughfare. The creek is channeled into three large parallel concrete culverts. The stream daylights west of the intersection of Villaview
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Road and East 185th Street. The sampling site was located at the top of the headwall along the north side of Villaview Road. Samples were taken from this downstream side of the stream. Since the creek travels through three independent chambers, samples were taken in the western and central channel, whichever had the strongest moving current.
The eastern channel typically was stagnant. Figure 4.20a shows the downstream side of the culverts and the sampling location situated above. The downstream view of the creek is shown in Figure 4.20b, which was taken from the sampling location.
Figure 4.20 Villaview Site Views: (a) looking at sampling site from downstream side and (b) looking downstream from sampling site
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4.2.14. Wildwood
This sampling site was in the Cleveland Metroparks, at Euclid Creek
Reservation, Wildwood Park. The sampling occurred along Villa Angela Drive. The sampling location is approximately 1000 feet from Lake Erie, where Euclid Creek empties into Lake Erie. The creek enters an oxbow at this location, where a general mixing pattern of water flow was frequently observed. The lakefront park consists of a mix of wooded land, walking trails, wetlands, a small boat marina, and beaches
(Cleveland Metroparks, 2014).
The sampling site was located at the pedestrian/roadway bridge prior to the parking lot for the boat launching ramp area. Samples were taken on the upstream side, at the center of the bridge. Figure 4.21a shows the upstream view of Euclid Creek taken from the left embankment of the bridge (looking upstream). Figure 4.21b shows a storm sewer along the upstream side of the right embankment.
Figure 21. Wildwood Site Views: (a) looking upstream from sampling site and (b) storm sewer at sampling site, upstream side
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4.3 Field Equipment
Stream characteristics were observed and recorded for each site visit. The following parameters and units of measure were logged: turbidity (cm), conductivity
(µS/cm), water temperature (oC), pH, dissolved oxygen (% and mg/L), air temperature
(oC), time of day, and stream velocity (fps). Triplicate water samples were collected and stored on ice for lab analysis of reactive phosphate and nitrates within 24 hours.
A clear, 120 cm long tube was used to measure turbidity as shown in Figure 4.22.
Water was filled to the top of the transparent tube then drained through the attached hose until the 4.5 Secchi disk located on the tube bottom was visible. A value of 120 cm meant clear water, or no turbidity. If the visibility was less than 120 cm, two independent measurements were taken and averaged. For example, a value of 5 cm meant the Secchi disk was just visible, but any additional water eliminated the visibility of the disk. Figure 4.23 shows typical views used for recording different turbidity depths.
Figure 4.22 Turbidity tube used to determine stream characteristics
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Figure 4.23. Measuring turbidity: (a) looking into the tube to view Secchi disk for unclear water (b) Looking at the tube filled with clear water.
Conductivity, water temperature, pH, and dissolved oxygen field measurements were taken with a Hanna HI 9829 Multiparameter Probe. The probe was immersed into a bucket containing stream water. Where feasible, the probe was also immersed into the stream to verify readings as shown in Figure 4.24.
Water velocity was initially recorded using a Geopacks Flowmeter. Flow could not be measured at the strongest current location for many of the sites. Approximate flow values were recorded using general observation methods. An object, such as the turbidity tube, was used to measure a distance along the stream. The time an object took to traverse this distance was recorded and repeated several times. The current was
63 approximated using the basic linear equation (푑 = 푣푡). If the stream flow was no stronger than a light wind current, no observation was recorded.
Figure 4.24. Multiparameter Probe used to determine stream characteristics: (a) Typical reading in bucket completed at all site locations (b) Back-up stream reading completed at sites where access to direct stream sampling possible.
4.4 Lab Analyses
As mentioned above, triplicate samples were collected during each site visit for nutrient analysis. All samples were analyzed in a lab within 24 hours. Each vial contained approximately 50 milliliters (mL) of stream water. Twenty mL was used for a reactive phosphate test and another 20 mL was used for a nitrate test.
Nutrient levels were tested with a Hach DR900 Colorimeter. For the reactive phosphorus test, Method 8048 (power pillows) was followed (HACH manual, Reactive
Phosphorus). For each water sample, two clear glass vials were filled with 10 mL of
64 stormwater per vial. One glass vial was used as the blank cell and the other as the sample cell. One packet of the phosphate reagent was added to the sample cell and shaken for 15 seconds. The sample cell was set aside for two minutes of reaction time. The blank cell was placed into the colorimeter, covered and zeroed. It was removed and the sample cell was read for its phosphorus (PO4) level in milligram per liter (mg/L).
A similar procedure was followed for nitrate testing. For each water sample, Method 8039 was followed using powder pillows(HACH manual, Nitrate). Once the nitrate reagent was added to the sample cell, it was shaken for one full minute. The sample cell was then set aside for five minutes then placed one at a time into the colorimeter and read for nitrate levels in mg/L nitrate as nitrogen. Figure 4.25 shows a typical vial used for testing. Figure 4.25. Typical glass vial
used for laboratory testing
4.5 Statistical Methods
Two-sample t-tests, matched paired t-tests, analysis of variance (ANOVA) and
Tukey comparison tests were performed for univariate data. A significance level of 0.05 and two-sided alternate hypotheses were used for all tests. These statistical methods were used to find any appreciable differences in the parameters collected for the 14 sites during wet and dry conditions.
For the investigation of conditions at an individual site, two-sample t-tests were used for comparing wet and dry conditions. Comparisons for multiple sites were
65 completed using matched paired t-tests. Statistics for these multiple site comparisons were analyzed using the same condition (wet versus dry) and the same collection day.
ANOVA and Tukey comparison tests were completed to analyze the difference in parameters for adjacent sites using Minitab software.
Linear regression was used to analyze bivariate data. A significance level of 0.05 and two-sided alternate hypotheses were used for tests for slope. Individual parameters collected versus time were analyzed. The strength of the relationship, coefficient of determination, and residual plots were evaluated. Additional bivariate analysis was completed for some individual sites using two of the collected parameters (regressions completed in Excel and Minitab software).
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CHAPTER 5
DRY WEATHER RESULTS & DISCUSSION
5.1 Dry Weather Flow Overview
This section details the results of the parameters collected during dry weather conditions. Bivariate data was compiled for each site to determine if any appreciable changes in nutrient level, pH, conductivity, turbidity, and water temperature occurred over time. One of these sites, Acacia, will be described in detail below. This statistical process was repeated for each of the remaining 13 sites and can be found in the Appendix
A: Dry Weather Results. Parameters were also compared between the two branches of
Euclid Creek, the East and Main Branch. The statistical differences for each branch were compiled for all 23 dry weather collection days and tested for significance at 0.05 level.
This comparison was calculated for both the upper and lower reaches of the two branches and is discussed in this chapter. The upstream tributary impacts to the branches were investigated and compared by evaluating the differences in nutrient concentrations between adjacent sites for all dry weather collection dates.
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5.2 Dry Weather Flow Conditions at Acacia
There was considerable variability in the phosphorus concentration at Acacia, ranging from a minimum 0.14 mg/L to a maximum of 0.79 mg/L. The lowest phosphorus level was the last collection on March 8, 2020 while the highest level was recorded on
September 11,, 2019. Phosphorus concentrations were observed to have some rapid changes during the summer. On June 30, the average concentration was 0.25 mg/L. Two days later, on July 2, the concentration more than doubled to 0.54 mg/L. There was no wet weather between the two collection dates. On July 2, there was active construction upstream of the collection site on the adjacent roadway, Cedar Road. Although construction on Cedar Road was present throughout the summer, the activities that day appeared to involve placement of new catch basins nearby, possibly influencing results.
Figure 5.1 shows the phosphorus concentrations over time for Acacia. The range of values
(0.65 mg/L) is almost four times as wide as the interquartile range (IQR) of 0.17 mg/L.
Figure 5.1. Acacia: Dry Weather Phosphorus Mean and Standard Deviation Levels over Time Based on Triplicate Samples
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Two colorimeters were used for analysis. Since there was a discrepancy in nitrate readings between the meters, testing was carried out with standard solution. Results of testing showed that the new meter provided accurate readings and the old meter was reporting inflated nitrate values. Figure 5.2 shows the results of 81 water samples tested for nitrate level using both colorimeters. Lower nitrate readings (0.0 – 0.5 mg/L) tended to result in closer outputs between the two meters than higher readings. Due to the discrepancy in readings, all subsequent readings were conducted with the new meter.
Figure 5.2. Dry Weather Nitrate Mean and Standard Deviation Levels over Time Based on Triplicate Samples Comparison for Old and New Colorimeter
Phosphorus comparisons were also conducted for the two meters. There was no significant difference between the reported phosphorus levels [p > 0.05] and therefore no accuracy issues. In general, all nitrate readings were below 2.0 mg/L. The higher nitrate readings shown below in Figure 5.3 were performed with the older Hach meter.
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Excluding the old meter readings, dry weather nitrate levels at Acacia ranged from 0.1 to
0.5 mg/L. There was little variation in nitrate readings (IQR = 0.2 mg/L). There may be a seasonal trend, with nitrate readings slightly increasing with warmer weather and declining with cooler temperatures.
Figure 5.3. Acacia: Dry Weather Nitrate Mean and Standard Deviation Levels over Time Based on Triplicate Samples
Nutrient levels peaked during the summer months. Mulholland and Hill (1977) studied weekly nutrient concentrations for two first-order streams in eastern Tennessee for seven years. They reported annual maximum concentrations of nitrates and soluble reactive phosphorus in both streams sampled during the summer and biannual minimum values in the spring and fall. Variability in phosphorus and nitrogen may be related to the connectivity of storm drains to upstream watersheds; which promotes rapid drainage and connectivity to diverse surface and groundwater sources (Janke et al., 2014).
Elevated concentrations of dissolved nutrients from these sources during dry weather baseflow can be substantial contributions to overall nutrient yields (Janke et al., 2014). 70
Headwater alterations, presence of buried sanitary sewers, potable water pipes, and storm drains can contribute to pulses of nutrients into streams (Kaushal et al., 2014; Paul and Meyer, 2001; Walsh et al., 2005; Allan et al., 2008).
The most common water quality problem in the United States is elevated levels of phosphorus in urban streams caused by nonpoint sources (US EPA, 1996). Urbanization may limit the natural process of phosphorus sorption by soil and biological uptake of phosphorus within riparian buffer zones (Sonoda and Yeakley, 2007). Soil saturated with phosphorus year-round may be an additional source for urban streams (Sonoda and
Yeakley, 2007). Landscape irrigation during dry weather conditions were shown to make large contributions to nutrient loads in residential catchments in a coastal residential community in Orange County, California (Toor et al., 2017). The highest daily nutrient concentrations for this study were found to occur from 6 pm to midnight. Pet waste nitrogen contribution exceeded lawn fertilizer contribution in a suburban Baltimore watershed and pet waste represented 84% of all phosphorus input in a Minneapolis-
Saint Paul watershed (Carey et al., 2013).
All efforts were made to minimize error for nutrient analysis. For small watersheds, Harmel et al. (2006) reports that there are four error sources leading up to nutrient analysis used for TMDL calculations: streamflow measurement, sample collection, sample preservation/storage, and laboratory analysis. The probable range error formula shown in Equation 2 below, the root mean square error propagation method, was used to estimate the cumulative water quality data uncertainty (Topping,
1972).