Will the San Antonio River ever be swimmable? KSAT Explains

San Antonio River is mainly a tourist attraction, but there are dreams of making it a place people can swim one day

Editor’s note: Two quotes in this article included typos as a result of an error during the transcription of an interview. The quotes have been corrected. It has also been updated to reflect the correct location of the Blue Hole on the property of the Headwaters at Incarnate Word.

The San Antonio River defines our community. It’s devastated our city while bringing prosperity. It’s also the reason that San Antonio exists.

However, few of us would willingly jump into the urban reaches of the San Antonio River. It’s not, by any stretch of the imagination, as clean as the nearby Comal or Guadalupe. Why is that?

“We have a trash problem,” explained Steve Graham, assistant general manager of the San Antonio River Authority.

Our area has had this problem for years, and while improvements have been made, change takes time.

Trash piled in the San Antonio River. (2022) (ksat12)

“That trash isn’t being done by me or us, all of us. No one ever wants to say I’m part of the problem, but we all are,” added Graham.

The Blue Hole

It’s not just trash that makes the San Antonio River a biochemistry lesson. To understand it better, we’ll need to float our way back to the beginning.

“This is the historic source of the water that feeds to the river,” explained Graham, referencing the Blue Hole.

Located on the property of the Headwaters at Incarnate Word, the Blue Hole sits as an icon of San Antonio’s history. After all, it is the spot where civilization began in the area. It was once a prolific spring.

“You’ll actually get this blue, iridescent kind of water flowing out of here. It’s really magical,” Graham said.

Magical, yes, but only on rare occasions. These days, it’s mostly dried up.

Image of a dry Blue Hole on the property of the Headwaters at Incarnate Word. (2022) (ksat12)
Image of The Blue Hole on the property of the Headwaters at Incarnate Word. (2022) (ksat12)

The Edwards Aquifer level at the J-17 well needs to be at 672 feet or more for water to flow out of the Blue Hole. So, the question becomes, “Where does the water in the San Antonio River that we see around the River Walk come from?”

River Walk water source

It came from wells for many years, but area leaders realized the aquifer needed protection.

“For the last 20 years, the primary source of the River Walk water and the water going downstream has been reclaimed water,” Graham said. “Now, that can all change when it rains. We get a lot of rain. Water in these springs does flow every couple of years as well. But, predominantly when you’re on the River Walk having a margarita, that’s reclaimed clean water for the most part and the zoo well making up most of the flow of the river.”

Effluent water, as it’s called, can make up as much as 90% of the water in the river. While the water comes from things like sewer plants, it is clean.

“Then when we place it under the UV lamp, if it fluoresces brighter than that, then it will be positive for E.coli,” explained Zachary Jendrusch, a Laboratory Supervisor at San Antonio River Authority, as he demonstrated samples.

Image of glowing water samples taken by the San Antonio River Authority that tested positive for E. Coli. (2022) (ksat12)

San Antonio River water contains E. coli

Yes, water from the San Antonio River does contain levels of E. coli, depending on what part of the river is tested. While the water going into the river may be clean, San Antonio’s pollution eventually takes effect.

E. coli, as you’ve probably heard, is a primarily unfriendly bacteria that can have bad results if ingested. The E. coli gets in our river from excrement.

“If you’re not picking up after your pet, then that, the excrement, is being flushed into the river, and that’s the source of E. coli,” said Jendrusch.

It’s not just Fido’s fault, though. Animals of all kinds contribute, including feral hogs who use the river as their restrooms. Even ducks’ waste helps to pollute the river. It’s one of the reasons they tell you not to feed the ducks.

How do we know that? A special machine in the San Antonio River Authority’s lab can break down whose gut the E. coli comes from.

And that leads us to one of the most common questions about the San Antonio River:

“Why can’t you swim in the waterway?”

“The reason why there’s more of the concern as far as pollutants go is because there are elevated levels of bacteria, mostly E. coli bacteria, largely, in downtown San Antonio,” explained Shaun Donovan, environmental sciences manager for SARA.

This is an important point. While you can’t swim in the river in San Antonio, that’s not necessarily the case farther downstream.

“The water quality does get better as you go downstream, as you get away from urban city centers. One of the biggest reasons is stormwater runoff. You have the accumulation on streets, on sidewalks, on lawns, parks,” Donovan said.

While rainfall is a good thing in most cases, it’s not good for water quality.

“We can have pretty good water quality in these long drought periods. But the minute it rains, the water quality goes horrible,” said Graham.

Then the question becomes: “What happens if you’re walking along the River Walk and you fall in?”

“You’re not going to get sick. You know, if you jump in the river and you take a few gulps of water, things might not be as good, but you’re not going to get sick just from falling in the River Walk,” said Donovan.

Safe to eat the fish

That goes for the species that call the river home, too. You’ve likely seen someone fishing in the river.

“It’s completely safe to eat fish in our system. The only exception is about a 15 or 20-mile stretch of Leon Creek that has an impairment for edible fish tissue, meaning you should not eat fish out of the lower portions of Leon Creek. But every other water body in our basin is considered safe for consuming fish,” said Donovan.

These kinds of water quality issues are not just a San Antonio problem.

“We are certainly not alone in the urban water quality issues, and it’s something that every single major city in the country deals with,” Donovan said.

River’s water quality improving

The good news is San Antonio is headed in the right direction.

“You talk to some people who have horror stories from 30, 40, 50 years ago about what the what the river was, and where we are now is light years beyond what it was in many, many years ago,” Donovan said.

Much of that is thanks to the moves taken by the community and the San Antonio River Authority, including inside their lab, where water testing takes place daily.

“The functions of the lab are critical because they really tell you all the other actions and decisions you’re making and actions you’re taking. Are they impacting the river in a meaningful way?” added Donovan.

That includes actions like the habitat restoration along the Mission Reach and the River Authority’s new campaign, “Don’t Let Litter Trash Your River.” A recent report card from the River Authority gave the San Antonio River a “B” overall, but it received an “F” for flood insurance and public trash.

“Awareness leads to action. Action leads to advocacy, where someday none of us would ever think to throw something on the street because we know that street will go to a curb and that curb and to a pipe. That trash will make its way eventually to some creek or tributary that goes to the San Antonio River,” said Graham.

That means more of the San Antonio River may be swimmable someday.

“I’m an optimist. So, you know, I hope that there’s something in the near future,” said Donovan.

“We often are at recreational standards that absolutely would allow you to go canoeing and kayak in what we call secondary recreation. But the primary rule is when you put your head in the water. We’re not there yet, but we do have a dream. That’s sort of our big dream is where and how can we make the river more swimmable,” added Graham.


About the Authors:

Justin Horne is a meteorologist and reporter for KSAT 12 News. When severe weather rolls through, Justin will hop in the KSAT 12 Storm Chaser to safely bring you the latest weather conditions from across South Texas. On top of delivering an accurate forecast, Justin often reports on one of his favorite topics: Texas history.

Myra Arthur is passionate about San Antonio and sharing its stories. She graduated high school in the Alamo City and always wanted to anchor and report in her hometown. Myra anchors KSAT News at 6:00 p.m. and hosts and reports for the streaming show, KSAT Explains. She joined KSAT in 2012 after anchoring and reporting in Waco and Corpus Christi.