1. Water Quality in the Galveston Bay System
Teresa Long
December 6, 2012
Advisor: Dr. Dennis Casserly
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2. Table of Contents
LIST OF TABLES ...................................................................................................................................................... 1
LIST OF FIGURES..................................................................................................................................................... 1
ABSTRACT .............................................................................................................................................................. 3
INTRODUCTION ..................................................................................................................................................... 4
WATER QUALITY IN GALVESTON BAY .................................................................................................................... 4
PROBLEM DEFINITION .....................................................................................................................................................5
Oyster Water Classifications .................................................................................................................................6
Total Maximum Daily Loads..................................................................................................................................7
Pollution Sources ...................................................................................................................................................9
GALVESTON BAY FOUNDATION INTERNSHIP ....................................................................................................... 10
DATA COLLECTION AND MANAGEMENT ............................................................................................................................10
.................................................................................................................................................................................12
VOLUNTEER WATER MONITORS......................................................................................................................................12
Texas Stream Team .............................................................................................................................................13
Bacteria Sampling and Analysis ..........................................................................................................................19
CONCLUSION ....................................................................................................................................................... 20
REFERENCES......................................................................................................................................................... 22
APPENDIX A. TMDL SEGMENT MAPS ................................................................................................................... 23
APPENDIX B. WHERE TO REPORT CONCERNS ....................................................................................................... 27
List of Tables
Table 1. Characteristics of Impaired Segments of Galveston Bay ................................................................ 7
Table 2. Concentration-Based Pollutant Wasteload and Load Allocations for Upper Gulf Coast Segments 8
List of Figures
Figure 1. Chart............................................................................................................................................. 12
Figure 2. Estimated Value of Volunteer Monitor Data ............................................................................... 13
Figure 3. Phase I & II Group Training
Figure 4. Phase III Training 14
Figure 5. Water Monitoring Kit ................................................................................................................... 14
Figure 6. Dissolved Oxygen Concentration Sample Prep
Figure 7. Dissolved Oxygen
Concentration Titration
16
Figure 8. Salinity Measurement .................................................................................................................. 17
Figure 9. pH Measurement ......................................................................................................................... 17
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3. Figure 10. Secchi Disk Measurements ........................................................................................................ 18
Figure 11. Enterolert Analysis ..................................................................................................................... 20
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4. Abstract
Water quality in the Galveston Bay system is impaired from untreated or improperly treated boat
sewage. Elevated levels of bacteria in the waters of the bay pose a serious public health threat if oysters
and other shellfish are consumed from those waters that are impaired. Commercial fishing for shrimp,
crabs, and oysters in Galveston Bay is a large part of the local economy and must be sustained. Not only
is sewage harmful to humans and aquatic life, it is unsightly and negatively impacts recreation and
ecotourism, which bring billions of dollars into the local economy every year. The Galveston Bay
Foundation is a nonprofit environmental watchdog group that is dedicated to preserving, protect and
enhancing Galveston Bay for both the present and future generations of diverse users. I participated in
many projects during my internship at Galveston Bay Foundation. This paper focuses on water quality in
the Galveston Bay system, developing and implementing various tools to assist diverse users of the
bay, and training a network of dedicated volunteer water monitors. Data collected by these volunteers
will be presented in a request for the U. S. Environmental Protection Agency to declare Galveston Bay a
No Discharge Zone.
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5. Introduction
Untreated discharge from just one weekend boater puts the same amount of bacterial pollution into the
water as the treated sewage of 10,000 people.Pathogenic bacteria resulting from discharge of untreated
or inadequately treated sewage can concentrate in aquatic life such as oysters and poses a serious
public health threat when humans consume contaminated oysters.
The Galveston Bay Foundation has been tasked with developing an Implementation Plan aimed at
reducing bacteria levels in Galveston Bay. The ultimate goal of this Implementation Plan is to secure a
No Discharge Zone declaration from the U.S. Environmental Protection Agency forthe Galveston Bay
system.
Achieving this goal is estimated to require three years of collecting and analyzing data with the help of a
trained group of volunteer water monitors. During my internship at Galveston Bay Foundation, I have
worked on many facets of collecting, analyzing, and quantifying data intended to support this goal.
Although I have served on various committees or workgroups and participated in educational campaigns
and other public outreach events, this paper will focus on water quality in the Galveston Bay system and
my efforts towards training these dedicated volunteers to collect representative samples, conduct
various analyses, and generate consistent, high quality data.
Water Quality in Galveston Bay
The Galveston Bay estuary is a semi-enclosed body of water where freshwater from rivers, bayous and
tributaries mix with salt water from the Gulf of Mexico. The Galveston Bay system comprises six
segments: Upper Galveston Bay, Trinity Bay, East Bay, West Bay, Chocolate Bay, and Lower Galveston
Bay. These six segments have a combined surface area of 519.1 square miles (1,344.5 square kilometers)
and are a valuable natural and economic resource. The Galveston Bay system is a rich, productive
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6. subtropical ecosystem which provides a valuable nursery for a diverse array of plant and animal species.
Living shorelines offer protection from storms. (Lester, 2002).
Galveston Bay has about 90,000 registered pleasure boats and the 3rd highest number of privatelyowned marinas in the United States (Galveston Bay Estuary Program, 2012). Approximately 5 million
people choose to make their homes and earn their living around Galveston Bay. Local economy relies on
the natural beauty and bountiful seafood supplied by the bay.
Several water-based industries such as recreational and commercial fishing, travel, and ecotourism
contribute billions of dollars to the local economy. The Port of Houston is the second-largest port in the
United States in tonnage and the eighth-largest port in the world. Petrochemical industries, which
produce one-half of the nation’s chemicals and one-third of the nation’s petroleum refining, rely on
transportation links provided by the bay for receiving raw materials and getting finished products to
market. (EPA, 2007). Commercial fishing for shrimp, crabs, and oysters in Galveston Bay worth a
combined $19 million annually contributes one third of Texas' annual commercial fishing income (EPA,
2007).
The UnitedStates EPA National Coastal Assessment comprehensive monitoring program rates overall
water quality in Galveston Bay as fair. Water quality index is rated poor, the sediment quality index is
rated fair to poor, the benthic index is rated fair, and the fish tissue contaminants index is rated good to
fair (EPA, 2007).
Problem Definition
Galveston Bay oyster fisheries produce more oysters than any single water body in the United Statesand
have been an integral part of local economy for over one hundred years. Prior to Hurricane Ike, the
annual Galveston Bay oyster harvest totaled between 3 and 4 million pounds valued at nearly 10 million
dollars.
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7. Oysters are filter feeders and have an important ecological role in the estuary. Oysters are capable of
filtering a volume of water per hour that is approximately 1500 times the volume of their body. A single
oyster filters 50 gallons of water in a single day. (Lester, 2002). Due to the large amount of water
filtered, any bacteria present in water concentrates in oysters. Human activities contribute to elevated
bacteria levels in the bay. Human consumption of oysters harvested in waters with high levels of
bacteria presents a serious human health concern.
Section 303(d) of the federal Clean Water Act requires all states to identify waters that do not meet, or
are not expected to meet, applicable water quality standards. Galveston Bay has nine segments which
are on the Texas Water Quality Inventory and 303(d) Listfor fecal coliform bacteria impairments. TMDL
Segment Maps showing these nine segments are found in Appendix A.
Oyster Water Classifications
Approximately half of Galveston Bay is under some form of oyster harvesting restriction (Galveston Bay
Estuary Program, 2012). When oyster waters are contaminated, or if waters areas surrounding oyster
beds have a high potential for contamination, the Texas Department of State Health Services will either
close or limit harvesting in these areas to commercial fishermen and the public. Oyster waters are
classified according to potential risk to consumers from eating oysters harvested in a particular area.
Four classifications are assigned to oyster waters:
1. Prohibited Area-- Area closed for the harvesting of shellfish which are not specified as Restricted
or Approved.
2. Restricted Area--Oyster harvesting is allowed except for direct marketing. Also called Restricted
Harvest Zones or RHZs
3. Conditionally Approved Area-- Open to oyster harvesting during periods with limited rainfall.
May be temporarily closed during significant storm events
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8. 4. Approved Area--Open to oyster harvesting
Each segments in the project area falls into one of the first three classifications.
Table 1. Characteristics of Impaired Segments of Galveston Bay
Total Maximum Daily Loads
States are required to develop a total maximum daily load (TMDL) for each pollutant contributing to the
impairment water body on the Texas Water Quality Inventory and 303(d) List. A TMDL defines total
pollutant load a water body can receive and still meet water quality standards. The Code of Federal
Regulations, Title 40, Section 130.2(i) allows states to establish a concentration-based TMDL for a
pollutant that is not readily controllable on a mass basis, such as a chemical pollutant typically present in
industrial outfalls.
Oyster Water Criteria:
•
Median <14 Fecal Coliform Units/100mL
•
90thPercentile <43 FecalColiform Units/100mL
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9. Table 2. Concentration-Based Pollutant Wasteload and Load Allocations for Upper Gulf Coast Segments
For oyster waters, a concentration-based (number of organisms per unit volume) measure of indicator
bacteria is used. Reducing bacteria concentrations in areas with levels exceeding limits for oyster waters
use is the primary purpose of this TMDL.
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10. Impairment of oyster waters is most likely due to marinas, recreational and commercial boat sewage
discharges, failing septic systems, wastewater treatment facility discharges of untreated waste,
migratory birds, wildlife refuges, and storm water runoff.
Pollution Sources
Human activities resulting from point source pollution and nonpoint source pollution can negatively
impact water quality in the Galveston Bay system. Point sources are single, identifiable pollution
sources subject to permit requirements and regulated by the Federal Clean Water Act and Texas
Law.Since they are effectively regulated and monitored, their impacts on water quality are not of as
much concern as nonpoint sources.Nonpoint sources originate from many sources which can be difficult
to identify. They are largely unregulated and not subject to permit requirements.
Trash and other contaminants are picked upby storm water runoff, transported across land, and swept
into the bay. Excess nutrients from fertilized agricultural lands, lawns, and gardens ultimately end up in
the bay. Bacteria from livestock, wildlife, pet waste, leaking septic systems and sewer lines are carried
into the bay by rainfall runoff.These organic materials, along with boat sewage, deplete dissolved
oxygen concentrationsdue to increased plant and bacteria growth. These organisms consume oxygen via
the respiration process.
Poor land management practices produce sediments from erosion that affects water clarity, reducing
the sun’s ability to penetrate water. Chemicals from pesticide application, motor oil, and antifreeze are
washed into the bay.
Analyzing data for trends and correlating it to human contributions can be an effective strategy to
define nonpoint source pollution.
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11. Galveston Bay Foundation Internship
Galveston Bay Foundation is a nonprofit organization that has worked to preserve, protect and enhance
Galveston Bay the past quarter century. Through programs in advocacy, conservation, education, and
research, the foundation strives to ensure Galveston Bay remains a beautiful and productive place.
Water quality issues are part of the Advocacy program, which seeks solutions to conflicts among diverse
users of the bay in an effort to protect long-term interests. Galveston Bay foundation has successfully
supported passage of state and federal legislation such as the Texas Oil Spill Prevention and Response
Act, Texas Estuaries Act, Texas Coastal Management Program, and the Federal Clean Waters and Estuary
Restoration Act of 2000.Currents efforts to have Galveston Bay declared a No Discharge Zone would
make discharging boat sewage, treated or untreated, illegal. Reducing bacteria levels in the bay and
improving water quality in general is of great importance in ensuring public health and local economy.
To date, only one coastal area along the eastern seaboard of the United Stateshas obtained the No
Discharge Zonedesignation. Marine waters adjoining the town of Wrightsville Beach, North Carolina
were declared a no Discharge Zone the by U.S. Environmental Protection Agency in February 2010
(Mallin, 2010).Determining which data is pertinent, how to collect and manage that data, and putting it
into a useable form is crucial in successfully seeking to have the Galveston Bay system declared a No
Discharge Zone.
Data Collection and Management
Once it was determined which data was relevant, research was conducted. Many sources including
boater registration records and journal articles were consulted.Pertinent fragments of information were
derived, categorized, and stored in spreadsheets for future use. A Technical Advisory Committee
comprised of experts in various fields has been formed. Examples of tools developed to collect and
disseminate information include web-based applications and maps.
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12. Galveston Bay Action Network (GBAN) is a crowdsource mapping web-based application designed to
allow the public to submit reports of water quality concerns theyobserve. Reports may be viewed in a
map based platform. These reports are reviewed by the Galveston Bay Advocacy team, and a
determination is made as to whether the observation should be reported to the proper authorities.
Contact information on where the public can report concerns to proper authorities is also accessible on
the GBAN website.Appendix B contains a copy of this information.
A Google map showing locations of marine pump-out facilities, both publically accessible and private,
has been developed and made public on the internet. Marinas were contacted to verify what type and
how facilities they provide and if they are operational. This map provides easily accessible information
to boaters. It is hoped that having this information in an easy to access format will reduce the number of
illegal discharges of boat sewage into Galveston Bay. Some mobile pump-out services may be scheduled
online, and phone numbers are readily available.In the future, this data will help determine if an
adequate number of pump-out facilities for boaters exist to properly dispose of sewage. It also provides
a means to identify locations that need more facilities.
A second Google map accurately depicts the location of volunteer water monitoring sites using map
coordinates. Both actively monitored sites are those sites where a volunteer monitor is desired are
shown.
Surveys were developed and administered both before and after educational presentations and other
activities as a means of tracking how effective educational campaigns aimed at reducing bacteria levels
and improving water quality in Galveston Bay. An example of a survey may be found in Appendix D.
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13. 6
5
4
Series 1
3
Series 2
Series 3
2
1
0
Category 1
Category 2
Category 3
Category 4
Figure 1. Chart
Volunteer Water Monitors
Texas Stream Team was established in 1991 and is administered through a cooperative partnership
between Texas State University, the Texas Commission on Environmental Quality (TCEQ), and the U.S.
Environmental Protection Agency (EPA). Trained, certified volunteers regularly collect and submit water
quality data on lakes, rivers, streams, wetlands, bays, bayous, and estuaries across Texas.
Water quality data collected by volunteers is extremely valuable. Sites are monitored at least monthly.
Combined, data points generated via chemical analyses, physical testing, and general observations of
the monitors produce a unique portrait of water quality parameters for that particular site and moment
in time. Over time, trend analysis provides many clues and can facilitate early identification of potential
water quality issues caused by nonpoint source pollution.
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14. Figure 2. Estimated Value of Volunteer Monitor Data
Galveston Bay Foundation acts as a branch of Houston-Galveston Area Council (HGAC), who partners
with Texas Stream Team, and trains, supports, and manages a volunteer team of water monitors. When
I joined the Galveston Bay Foundation as a water quality intern, the program was in its infancy and had
nine volunteers that had previously been managed by HGAC.
One of my first accomplishments was becoming a Texas Stream Team Certified Trainer and developing a
field guide specifically for the Galveston Bay Foundation Volunteer Monitoring Team which may be
found in Appendix C. In order for our volunteers to interact and share knowledge unique to water
quality testing in Galveston Bay, a Facebook group has been created. Since I began training volunteers,
the number of certified volunteer monitors has increased from nine to twenty-nine, with four
volunteers scheduled for Phase III training in December 2012.
Texas Stream Team
To become a certified Texas Stream Team Volunteer Water Monitor, three phases of training must be
completed.
Phase I – Classroom trainingthat includes orientation, demonstration, and practice
Phase II – Group field training, individual testing, focus on recordingfield observations
Phase III – Site visit that includes site assessment by the certified trainer, individual training on
chemical and physical testing, evaluation of proficiency, and certification
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15. Figure 3. Phase I & II Group Training
Figure 4. Phase III Training
Phase I and Phase II Training requires a full day of instruction and is conducted in a group setting. Phase
III Training is usually done at an approved monitoring site which the volunteer will regularly monitor.
Volunteers are provided a kit and trained to conduct testing and record data in a manner that produces
clear, consistent results across the monitoring group.
Figure 5. Water Monitoring Kit
Core water quality parameters monitored by volunteers include:
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16. Dissolved Oxygen
Salinity
pH
Temperature (Air and Water)
Water Transparency
Depth
Field Observations
A sample is collect from just beneath the surface of the water by lowering a white bucket, allowing it to
sink, and pulling it up. Proper footwear should be worn to prevent slips, trips, and falls.
Dissolved Oxygen Concentration
Dissolved oxygen concentration is a measure of the amount of oxygen freely available in water.
Concentration is measured in milligrams per liter (mg/L). This analysis requires more skill than the other
tests and proper technique is essential.PPE (safety glasses and gloves) is required for this analysis. Two
sample bottles are filled with sample water and capped under the surface of the water. Manganous
sulfate and alkaline potassium iodide are added to the samples, which are inverted and allowed to settle
twice. Sulfuric acid is added, and the samples are slowly inverted for 3-10 minutes. At this point,
dissolved oxygen levels are fixed and the titration can be carried out anytime within a 6 hour period.
When I began training volunteers, many had difficulty getting the two aliquots to agree to within 0.5%. I
discovered this was due to not understanding how to read a meniscus, and began spending extra time
teaching this aspect of the analysis. Volunteer monitors come from all walks of life and have various
levels of scientific knowledge and experience. Successful Phase III training and certification depends on
the ability of the trainer to teach techniques on the level of understanding the volunteer possesses.
For the titration, 20ml of sample is added to a vial. A titrator syringe is filled with sodium thiosulfate and
the sample is titrated to a pale yellow color. A starch indicator is added and the sample is titrated to a
clear endpoint. Dissolved oxygen content in mg/L is equal to mg of titrant used. Results of the two
aliquots must agree to within 0.5%. An average reading from 2 samples is recorded.
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17. Seasonal variations exist. There is an inverse relationship between dissolved oxygen concentration and
temperature and dissolved oxygen concentration and salinity.Dissolved oxygen concentration can be
correlated to excess plant and bacteria growth caused by excess nutrients. Dissolved oxygen levels are
perhaps the most important indicator the ability of a body of water to support and sustain aquatic life.
Healthy aquatic ecosystems are dependent on dissolved oxygen concentration:
•
•
•
<2 mg/L: Fatal to most species
<3 mg/L: Stressful to most species
>5 mg/L: Sufficient for most species
Figure 6. Dissolved Oxygen Concentration Sample Prep
Figure 7. Dissolved Oxygen Concentration Titration
Salinity
Salinity measures the concentration of dissolved salts in water.Concentration is measured in parts per
thousand (ppt). In an estuary, fresh water inflows from streams and rivers combine with ocean water.
Dissolved salt content affects distribution of plant and animal life, and concentration of dissolved oxygen
decreases as salinity increases.
A large graduated cylinder is filled with sample water, a thermometer is hung in the graduated cylinder
so that it is totally submerged. A hydrometer is lowered into the graduated cylinder it does not touch
the thermometer or sides of the graduated cylinder. Once the hydrometer has stop moving,
temperature is read underwater and recorded. Specific gravity is read and recorded. Salinity is
determined using tables provided in the Field Guide provided in Appendix A.
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18. Figure 8. Salinity Measurement
pH
pH is a measure of hydrogen ion concentration and is measured in standard units on a scale of 0-14,
with 0 being acidic, 7 neutral, and 14 basic. Most suitable pH range for aquatic life is 6.5-9. Significant
changes in pH, either sudden and dramatic or a steady increase over time, may be an indicator of
problems with water quality.
A small test tube is filled to the line with sample water. An indicator is added, the vial is inverted 10
times, placed in a viewer and pH is determined by a color comparison.
Figure 9. pH Measurement
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19. Temperature
Air and water temperature are measured in degrees Celsius (0C), ±0.50C . Air temperature is measured
by hanging the thermometer out of sunlight and wind. Water temperature is measured in the bucket of
sample water and read underwater. Temperature has a direct correlation to other parameters being
measured, such as dissolved oxygen content, and can be used by data managers to determine percent
oxygen saturation.
Water Transparency and Depth
Water transparency and total depth are measured in meters (m). Transparency is a measure of turbidity
or clarity.Proper footwear should be worn when performing this testing to prevent slips, trips, and falls.
A Secchi disk is lowered into the water until it disappears and depth is measured. The disk is lowered
again until it disappears, then is raised until the white areas are just visible and depth is recorded. The
two depths are averaged and recorded. Total depth of the exact point being sampled is also recorded
and used in trend analysis. The Secchi disk is lowered into the water until the cord becomes slack, and
then raised until straight. Total depth is measured and recorded.
Figure 10. Secchi Disk Measurements
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20. Field Observations
Field observations are extremely valuable. A sudden absence or severe reduction in aquatic life is an
indicator that something is amiss. Since a volunteer monitor records these observations on a regular
basis, they have first-hand knowledge of water quality conditions that may not be immediately apparent
from chemical analysis. Parameters measured and recorded are:
•
•
•
•
•
•
Algae cover
Water surface conditions
Current weather conditions
Tide Stage
Water clarity, color and odor
General observations that may affect the sample collected, such as nearby boat traffic or
unusual foam, etc.
Bacteria Sampling and Analysis
Volunteers are trained to collect samples for bacteria analysis. A chain of Custody Form is completed for
all samples. Samples are analyzed using the IDEXX Enterolert method. Enterococcus is an indicator
bacterium that is normally found in the intestines of humans. Since this organism survives in salt water,
it is a better indicator of human sewage in brackish waters than fecal coliform.
Getting Galveston Bay Foundation’s bacteria lab operational has been one of the projects I’ve worked
on for my internship. Volunteer monitors have been trained to collect samples, and the next step is
training those that have the aptitude and time to perform and become competent at the laboratory
analysis. Quality Control measures have been determined and documentation methods included in an
EPA Quality Assurance Project Plan. A Standard Operating Procedure adapted from the City of Houston
Environmental Lab’s procedure is in the final draft stage.
Sample Collection
Samples are obtained from the bucket grab sample before any other monitoring activities occur to avoid
contamination and must be placed on ice immediately, then delivered to the lab within a 6 hour period.
19

21. Samples are collected in pre-labeled Whirlpak bags containing a tablet to neutralize chlorine. Other
measures to prevent contamination include:
•
•
•
•
Using a sterilized beaker to obtain sample from bucket
Never pre-rinse the sample bag
Do not touch inside of sample bag
Never immerse sample bag in the bucket, always pour sample water into the sample bag
Laboratory Analysis
Once samples arrive at the lab, they are prepped and placed in an incubator at 410C ±0.50C for a 24 hour
period. Samples are checked for a blue fluorescence under ultraviolet light. The number of cells
displaying fluorescence is counted and Enterococci concentration is calculated in colony forming units
(cfu’s) by using Most Probable Number charts. A level of ≥35cfu’s is considered to be above limits set for
recreational waters by TCEQ.
Figure 11. Enterolert Analysis
Conclusion
Galveston Bay Foundation’s draft Implementation Plan has a solid foundation in place for collecting,
analyzing, and presenting data to the U.S. Environmental Protection Agency requesting Galveston Bay to
20

22. be declared a No Discharge Zone. Supportive efforts from the Technical Advisory Committee and the
Certified Volunteer Water Monitor Group will continue to be invaluable and are vital to the success of
this worthwhile endeavor. Every effort was made to ensure the continuity of the many projects I started
that require long term attention.
I am proud to have served and contributed in the initial stages of this massive undertaking. I will
continue to support this effort on a volunteer basis. Protecting and preserving the quality of water on
our planet is essential to sustain life. There is no life without water. There is no substitute.
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23. References
Chapter 5: Gulf of Mexico National Estuary Program Coastal Condition, Galveston Bay Estuary
program. In (2007). National Estuary Program Coastal Condition (pp. 289-301).
Retrieved from
http://water.epa.gov/type/oceb/nep/upload/2007_05_09_oceans_nepccr_pdf_nepccr_
nepccr_gom_partg.pdf
Lester, J., Gonzolez, L., Sage, T., &Gallaway, A. (2002). The state of the bay: A characterization of
the galveston bay ecosystem. (2nd ed.). Webster, TX: Galveston Bay Estuatry Program.
Mallin, M., Haltom, M., Song, B., Tavares, M., &Dellies, S. (2010). Bacterial source tracking
guides management of boat head waste in a coastal resort area. Journal of
Environmental Management, 91(12), 2478-53.
Texas Commission on Environmental Quality, Total Maximum Daily Load Section. (2009). Six
total maximum daily loads for bacteria in waters of the upper gulf coast segments 2421,
2422, 2423, 2424, 2432, and 2439. Austin, TX:
Why is galveston bay important to you?. (2012). Retrieved from
http://www.gbep.state.tx.us/why-important/why-important.asp
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24. Appendix A.TMDL Segment Maps
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25. 24

26. 25

27. 26

28. Appendix B. Where to Report Concerns
27

29. 28

30. Appendix C. Field Guide
29

31. 30

32. 31

33. 32

34. 33

35. 34

36. 35

37. Appendix D. Source Tracking Documents
36

38. 37

39. 38

40. 39

41. 40