Water Works
Science and service converge in a Rollins field study that has helped bring clean water to the Dominican Republic for more than two decades.
October 09, 2017
It’s May 2017 on the island of the Dominican Republic. It’s hot. Sticky. Almost unbearably so. But Rollins chemistry professor Pedro Bernal is unfazed. There are water filters to assemble. There is information to collect and numbers to record. And it’s here, doing this work, that Bernal is most energized.
“I do pretty well in the heat,” Bernal says, remembering the two weeks he spent in the rural center of his native country this spring. “They’re going to have to send a medevac to evacuate me from one of those mountains someday.”
For the better part of his career, Bernal has led teams of Rollins students to the island to conduct field studies on water sanitation—monitoring water quality in tiny, remote villages and installing water filters in people’s homes. This spring, he led a class of six students to the Caribbean as the cap to his Maymester course, Water, Sanitation, and Health in the Dominican Republic.
Over the course of the 21-year-old project, Bernal and his charges have installed more than 20,000 water filters in rural communities across the island, leaving a lasting impact on the Dominican people and creating life-changing—and sometimes career-defining—experiences for generations of Rollins students.
A Global Crisis
Around the world, 2.1 billion people lack access to safe water at home.
“For most people in developed countries, municipalities do water treatment and you go to the tap and get it,” explains Bernal. “A lot of people around the world don’t have that luxury.”
The breadth of impacts this crisis has on lives around the world can be hard to imagine:
- 263 million people spend more than 30 minutes round-trip collecting water.
- 159 million people are dependent on surface water.
- 1.8 million people die from diarrheal diseases each year—the majority of them under the age of 5.
“I knew it was a problem in my country, but I didn’t know it was that bad,” says Mariela Mera ’20, a chemistry major. Like Bernal, she hails from the DR—the capital city of Santo Domingo. After expressing an interest in chemistry as a high school student, Mera was introduced to Bernal through her uncle, who happens to be a lifelong friend of the professor. During her senior year, she drove out from the capital to meet Bernal on one of his annual visits to the island. That experience led her to Rollins and, eventually, back to the DR as one of Bernal’s student scientists.
“You see people getting water from the rain and using a dirty cloth to filter it,” she says. “Then you see how the filter works with that same water and now, thanks to the filters, they’re drinking clean water.”
Bernal’s project employs a simple approach—Household Water Treatment and Safe Storage—which the World Health Organization has designated as a viable solution for water sanitation.
“Our filter is a device that people can put in their own homes, so they can purify a small amount of water that is good enough to drink,” he explains. “When I was first exposed to this work, there was already a filter in place. Since then we’ve done tons of work on the ground, and we have tweaked the system. Our filters are an improved version of what already existed.”
How It Works
Water is collected in a simple, 5-gallon bucket.
A precise amount of bleach, a product that’s widely available throughout the country, is added to the water using a syringe. This kills the dangerous bacteria and microbes that may be present in the water.
After 45 minutes, the water runs through a sediment filter (similar to a coffee filter) to remove the dirt.
A second cartridge, a carbon filter, removes the chlorine and makes the water drinkable.
In the Classroom
“The first two weeks of the course are designed to teach you how to use all the equipment that you’ll need once you’re in the DR,” says Caroline Rosendahl ’18, a marine biology major.
Students also spend a large portion of that time studying the issue at hand.
“I knew about the water crisis,” Rosendahl says, “but I didn’t know how big it was until I started to read about how many people are actually suffering from not getting enough water—or even worse than that, clean water. Then, when we were in the DR, it was not just a text. We were seeing real-world problems.”
On the Ground
In the field, students assist Bernal in microbiological and chemical assessments of water in some of the DR’s most remote villages.
“We check pH, turbidity, and chlorine,” Rosendahl explains.
The numbers determine immediate next steps—whether the team will install new filters or service existing filters—and contribute to Bernal’s collection of long-term data about the water filters.
“I have data that goes back to 2001 and gives me a sense of how the filters are working,” Bernal says.
He estimates that in the communities he works in currently, he and his students have installed roughly 6,000 filters. Some of the filters have been in use daily filtering water for more than a decade.
San Bernal
Bernal has been engaged in community work in the DR since 1993. “The story, as you might imagine, is complex,” he says. It all started with a church flyer.
“It had an article about some folks who were doing work in the border region of the Dominican Republic and Haiti through a diocese of the Catholic Church. And one of the things they were working on was water.”
Twenty-one years later, Bernal has garnered a reputation on the island that matches the fondness his students feel for him at Rollins.
“People there love him,” Mera says. “He’s like a saint. They call him San Bernal.”
“It gave me a direction.”
A graduate of Bernal’s DR field work, Liz Thiele ’01 has spent her career focused on waterborne diseases. This summer, Thiele returned to the island with Bernal’s Maymester course—this time as a technical consultant for the Carter Center, focused on the eradication of guinea worm. Thiele, who is currently a visiting scholar at Vassar College, remembers how the course inspired her early in her career.
“My experiences with this work have enriched my life in ways I never could’ve predicted,” Liz Thiele ’01 says.
“I remember that first trip when we were leaving the country and just kind of thinking to myself, ‘This can’t be the only time I ever come here.’ The spirit of the country infected me a little bit,” she says. “And then that just sort of continued to grow with the subsequent trips. It gave me a direction. It gave me a different perspective on how I could use my interest in biology to answer questions that were directly related to public health.”
Lasting Connections
Days in the field are long and hot. There is a lot of walking—much of it uphill—and carrying heavy equipment. “The heat is so intense,” admits Mera. “The humidity. The sun never stops. The sun is always there.” But it’s the moments in between that really resonate.
“They are walking into people’s homes, talking with them,” Bernal says. “Eating with someone who’s cooking for them. It’s community engagement at its best.”
“People from the countryside share absolutely everything with you,” Mera says. “It’s incredible. They will ask you to sit down, and then they will go to the neighbor’s house to find chairs.”
“And not only that—they’ll come with a tray of coffee!” adds Rosendahl.
“The kids were the ones showing us around because the kids were the ones who knew which houses we needed to go to,” Mera says. “They were showing us which houses needed their water checkups and which houses didn’t have a filter.”
“I think what it always came down to was just connecting with people,” Thiele says. “They’d come up to you and say, ‘My babies haven’t had diarrhea since we’ve been using the filters.’ So, you know that in at least these specific instances the work is making a difference.”
A Direct Impact
In order to test for the presence of E. coli, samples must incubate for at least a day. Rosendahl remembers when one sample came up positive for the dangerous bacteria.
“That’s when Dr. Bernal said, ‘We have to alert them immediately,’ she says. “So, in that moment, you know you could’ve saved someone from having severe, life-threatening diarrhea. Knowing that you’re not just learning but doing something good for someone outside your country—that’s really important to me.”
“I didn’t even know that you could actually mix chemistry with community work,” Mera says. “So it actually made me realize that what I’m doing currently is really what I want to do. When I go back next time, I want to go as a student leader.”
“I happen to think that this is an incredibly significant experience for students,” Bernal says. “If I could do it more than I do it, I would. It’s probably my favorite activity. There’s a great deal of satisfaction that comes from seeing that you are having a direct impact on someone’s life.”
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