Ensconced by limestone bluffs, the picturesque lagoon known as the Blue Hole in Georgetown beckons locals who want to spend the day wading, swimming, fishing, or picnicking. It’s an idyllic spot made even more inviting at this time of year, when early summer rains assure that the glimmering waters of the San Gabriel River are high and the oak trees are particularly verdant.

But just 14 miles upriver lies the Liberty Hill Wastewater Treatment Facility. In the past seven years, the plant has repeatedly come under investigation after residents in Georgetown, Leander, and Cedar Park have complained that the parts of the San Gabriel flowing through their backyards—waters in which their children had once played and even been baptized—were now covered in algae, filled with foam, and stinking of chlorine and sewage. Last year, the Texas Commission on Environmental Quality (TCEQ) issued a report citing the wastewater facility for discharging raw, untreated sewage as well as dangerous levels of E. coli bacteria and unacceptable amounts of algae-producing ammoniacal nitrogen and phosphorus. Last month, the TCEQ cited the plant again for releasing 3,000 gallons of partially treated wastewater; at the site of the outflow, an investigator discovered 18 inches of sewage and shudder-inducing blood worms.

The city of Liberty Hill disputed the 2018 report and is negotiating the financial penalties assessed for past violations.

Scout Gockel ’22 was still a high-school student when his mother read about the San Gabriel controversy in the newspaper and mentioned it to him. As an amateur scientist, he was intrigued. Originally fascinated by genetics and molecular biology, he developed a particular interest in researching water quality thanks to a summer internship after his junior year under the mentorship of Dr. Stuart Reichler, an associate professor at the Practice College of Natural Sciences at the University of Texas (UT) at Austin. So the San Gabriel story stoked his imagination, but for the time being, he simply filed it away in the back of his mind.

From left to right: Nicole, Vanessa, Edu, and Scout preparing to measure dissolved oxygen at one ... From left to right: Nicole, Vanessa, Edu, and Scout preparing to measure dissolved oxygen at one of their sites in Liberty Hill.

Question and hypothesis

After arriving at Southwestern University for his first year, he enrolled in an introductory biology course as well as the Ecolab Practicum, a class that focuses on environmental monitoring and conservation and gave him further opportunities to practice water-quality testing. Both experiences confirmed what he already knew from his years in high school: he wanted to major in biology. Then, he learned about the research opportunities made available by the King Creativity program. “So I started researching the pollution in the San Gabriel immediately and found it was way more involved. I thought it was going to be a river monitoring job, but now, it was a legitimate investigation,” he states.

In addition, there didn’t seem to be any ongoing monitoring of the South Fork of the San Gabriel. Gockel was confused: if local authorities were aware of water-quality problems in the river, why wasn’t continued monitoring taking place, and why wasn’t anyone doing anything to improve conditions? Undeterred by his status as a first-year college student, the enthusiastic young biologist decided that he might as well investigate himself.

Gockel recruited a team of students with one overarching goal: to determine the extent of the contamination in the San Gabriel River. He sought out fellow Ecolab student Nicole Rajtak ’22, an environmental studies major and Spanish minor who says she knew nothing about the controversy until Gockel told her about it. They were joined by Vanessa Jones ’22, Edu Swarts ’22, and Miriam Ibarra ’19. Thus began a two-semester project that, Gockel says, local residents “should care about, even if you hate the environment, because the San Gabriel River and the Edwards Aquifer feed into each other, and people derive their water from both of these sources.”

Scout and Vanessa wade through the San Gabriel to collect aquatic macroinvertebrates. Scout and Vanessa wade through the San Gabriel to collect aquatic macroinvertebrates.Methods and materials

Rajtak explains that during the past two semesters, the team systematically collected water-quality data from five sites: two upstream from the Liberty Hill plant, one downstream, and two much farther downstream in Georgetown. “There’s a wastewater treatment plant in between those, which acts as a control: this is how a normal plant would affect the water compared with how much the Liberty Hill facility is changing the water,” she adds.

The first step of the process entailed using probes to test the levels of nitrates, phosphates, and dissolved oxygen in the river. Excess nitrates and phosphates, which are discharged by treatment plants but can also come from untreated sewage and runoff from fertilized grounds, cause a kind of pollution called eutrophication, which leads to explosive growths of algae (i.e., algal blooms). Algal blooms cause foul odors, deplete oxygen in the water, and block sunlight that would feed underwater plants, resulting in dead zones of aquatic flora and fauna. When the algae themselves die, they decompose, which reduces the concentration of dissolved oxygen, further suffocating larger life forms such as fish.

Fecal-indicating bacteria collected from the San Gabriel River. Fecal-indicating bacteria collected from the San Gabriel River.Simultaneously, they collected water samples to test for E. coli, a species of bacteria specific to fecal matter from humans and other warm-blooded animals. Although E. coli can itself cause a number of illnesses, its more important use in the students’ experiment was to indicate possible sewage contamination and therefore the presence of other pathogenic, or disease-causing, microorganisms.

The second step entailed macroinvertebrate sampling—at the mention of which Gockel’s expression becomes rapt while he practically rubs his palms together with avidity. Macroinvertebrate sampling might sound like a fancy new dining trend, but in actuality, it’s an important procedure that Gockel first became enthralled by during his internship at UT. Macroinvertebrates are small organisms without a backbone, such as dragonflies, beetles, worms, leeches, and small crustaceans; collecting and analyzing such creatures can help researchers determine the health or condition of the water bodies in which they’re collected because they respond in various ways to pollution. “We would shoo bugs into this big net, take a small sample of what we got, remove the bugs in the lab, and identify them,” says Rajtak. “The premise of that is the bugs have a certain threshold of pollution they can live in, so if you collect bugs that can only live in extreme pollution, you have a problem.”

Gockel adds, “The chemical and bacterial data that we collected in this area are like a photograph: they tell you at one specific moment how the river is doing. But the bugs have to live in this environment for weeks to months, so macroinvertebrate sampling gives a much bigger picture of what is happening over time.”

Collecting insects may sound romantic to young scientists who are fascinated by fieldwork, but there was one major hiccup when it came to collecting specimens in the spring: the weather. Rajtak recounts that during their first outing, “it was a Saturday, and it just poured that week, and we got really weird results.” At other times, cold temperatures hampered their efforts, but Rajtak says their fearless team leader remained undeterred. “It was 12 degrees with wind chill one time, and we were making fun of Scout because he was out there in the water saying, ‘I’ll be fine, I’ll be fine’!” she laughs. Gockel confirms, “I had my hands in the water, and I thought, ‘I don’t want to get frostbite. This is a mistake.’ But I still got enough bugs, so it was worth it!”


The young scientists revealed some of their findings during the 2019 King Creativity Symposium and again at the 20th annual Research and Creative Works Symposium. However, the story ends on something like a season-ending cliffhanger because they are reluctant to publish the results of their experiments without further research. They do, however, hope to continue sampling next year depending on whether they can acquire funding for the water chemistry portion of the project. They also invite incoming and returning Southwestern students to contact them if they want to join the team in 2019–2020.

In the meantime, one of the most significant outcomes of their research has been their own learning. “I had no idea how to do any of this. Scout taught me and the rest of the students who work with us,” Rajtak reflects admiringly. “I also got to learn that I really like to be in the field, which I couldn’t have done in the classroom.” She’s looking to gain further field experience through conservation and other internships related to her major. 

Gockel says he loved “everything” about the project: “I loved getting to do something I was so excited about every weekend, and I loved getting to introduce other kids to something that they maybe wouldn’t have learned about otherwise.” He feels the San Gabriel River project gave him a better understanding of—and a chance to refine—various techniques he had learned previously. For example, he and Rajtak had the opportunity, rare for undergraduates, to work with an autoclave, an industrial sterilizing device that kills bacteria, viruses, fungi, and spores using pressurized steam and heat. “And we’re freshmen who know how to use it!” Gockel says appreciatively. But another major takeaway was just the process of planning a major research project from beginning to end. “The main thing I learned is how organizing is important,” he shares. “Before, I was just learning how to do the various techniques, like sampling and calibrating probes. But now, I have to do all the research before even proposing project, talking with different science professors and reading their papers. Then, I have to find students like Nicole, and I have to think about how to recruit other students who would be interested. After we won the grant, I had to figure out how to create a budget and decide about all the equipment we’d need even before even stepping into the lab, get an account with Fisher Scientific [an international laboratory supply company], and buy it—all of this as a first-year student.” 

What the group also hopes will come of their project is raising awareness about the wastewater controversy. “The goal here is not to crack down on anyone. It’s just to share what we found,” Gockel maintains. “Someone who’s professionally trained should get in there and do something about this if something looks concerning. We’re concerned, so we’re trying to raise awareness of the issue.”

“Not to mention the San Gabriel is a really important river, so not just college students should be monitoring the water quality,” Rajtak adds. Gockel explains, “The San Gabriel River and the Edwards Aquifer feed into each other. People derive their water from both of these sources. So even if you hate the environment, you should care about this.”

Fecal-indicating bacteria collected from the San Gabriel River.


Ultimately, Gockel and Rajtak are excited to have had the experience to do professional-level water-quality field research during their first year of college. They express gratitude for their advisor, Visiting Assistant Professor of Environmental Engineering Rebecca Edwards, and for the support and lab space lent by Director of First-Year Biology Laboratories Stacie Brown and Director of General Chemistry Labs Willis Weigand. They say they also appreciate that various Southwestern staff and professors in the sciences contributed their expertise and supplies, such as Biology Lab Technician Christy Schaller and Professors of Biology Ben Pierce and Romi Burks.

Rajtak advises future Southwestern undergraduates committed to research to talk to everyone they can, from professors to “anyone you think might have a vague interest” in the project. Gockel agrees: “Having talked to so many professors and people about the project, we were able to make it better and better because everyone had ideas of how to make the data better. It’s going to be better the earlier you get people’s input.”

Of the King Creativity grant and the Research and Creative Works experience, Gockel comments, “There’s always a way to get things done at Southwestern. You can get the funding. We’re just baby freshman, but we got money from this cool grant to do something that genuinely affects things. So go big, or go home.”