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In early May, San Pedro Creek Culture Park opened with an outdoor festival that marked the transformation of a former concrete-lined channel to a public space with murals and fountains.
Visitors, including children, splashed in the creek in the new Plaza de Fundación, which commemorated San Antonio’s founding on the banks of the crystal-clear creek in 1718. Construction costs for this first phase of the creek’s restoration reached $57.3 million.
But by the end of May, officials closed the park again for modifications. It turned out that bacteria was to blame.
Bacteria remain the largest single pollution problem in the San Antonio River basin, according to the San Antonio River Authority’s most recent Clean Rivers Report. Of the 33 stream and river segments in the report, 57 percent are officially considered impaired because of bacteria.
Bacteria, such as E. coli, serve as indicators for fecal contamination in outdoor waterways. This can lead to skin infections and gastrointestinal illness, especially if a swimmer accidentally swallows contaminated water.
The report is a comprehensive look at all of the rivers and creeks that drain to the San Antonio River, from the uppermost headwaters in the Hill County to the bays and estuaries of the Texas Gulf Coast. It relies on seven years of water quality data from routine sampling by the River Authority, the Texas Commission on Environmental Quality (TCEQ), and others.
The report focuses on average bacteria counts and long-term trends. But zoom in closer, and it’s clear bacteria levels tend to rise and fall in local waterways based on rainfall.
For example, levels of E. coli in San Pedro Creek were relatively low in early May during the park’s opening, according to River Authority data.
However, that changed after a rainstorm on May 20. The storm was light, dropping only 0.2 inches at the San Antonio International Airport. But this small amount of runoff caused bacteria levels to spike in San Pedro Creek and by May 25, levels of E. coli in the creek had shot up more than 200 percent to 460 instances per 100 milliliters.
That’s more than three-and-a-half times the state standard of 126 instances per 100 milliliters at which a creek is considered safe for swimming.
The spike also was short-lived. By the end of May, bacteria levels in the creek had dropped back to just 36 instances per 100 milliliters.
The park reopened in mid-June after officials spent $120,000 making the creek shallower to discourage children from swimming, among other repairs.
Bacteria in local waterways come from many sources, said Melissa Bryant, who manages the River Authority’s environmental sciences department.
Bird droppings collect on parking lots and wash into the river during storms. Feral hogs leave their waste along the river’s banks. Spills and overflows from sewage lines leak thousands of gallons of raw sewage into the river. Destroying wildlife habitat for development pushes animals into riparian areas.
Contributing to the problem are the vast areas of pavement and asphalt where bacteria collect, Bryant said. Rainstorms then cause these bacteria to wash into the San Antonio River and its tributaries.
“We can see during a storm event that our E. coli levels spike up,” she said.
When people think of water pollution, the image that typically comes to mind is a pipe dumping some kind of foul sludge into a creek. That kind of pollution is known as point source pollution, and it’s the focus of most of the regulations across the U.S. meant to protect waterways.
In Texas, entities like sewage plants or industrial sites that would discharge their wastewater into a river or creek must get a permit from the TCEQ. They have to meet water quality standards and can face fines or having their operations shut down if they fail to comply.
No enforcement like that exists for bacteria pollution, which falls under the umbrella of nonpoint source pollution. That’s what makes it a much more complicated issue and a more difficult one to solve.
“TCEQ can enforce the wastewater treatment plant and others, wherever they have a discharge permit, that’s where they can really regulate,” Bryant said. “But the nonpoint source, it’s going to be up to citizens to proactively advocate green streets … for development to be done more sustainably, for protecting our riparian areas. Those are the things that limit the impact of our runoff.”
River Authority officials are pushing for a greater embrace of design techniques known as low-impact development, which can help filter pollutants like bacteria out of stormwater. These include bioswales, rain gardens, permeable pavement, among others.
Environmental groups like the Greater Edwards Aquifer Alliance and Environment Texas also want the City to begin requiring more low-impact development in its building codes, something that’s only currently required for certain areas near the river downtown.
“They’ve been talking about it for quite some time now, but we haven’t seen action,” said Luke Metzger, Environment Texas’ director.
On Thursday, Environment Texas released a report compiling state data that shows bacteria contamination on popular swimming areas. These included the San Antonio River and beaches near Corpus Christi and Galveston Bay.
Many hold out hope that San Antonio can day have waterways officially considered safe for swimming.
“A lot of the numbers in the report, you’ll find that they’re not that far off the 126,” said Charles Lorea, who drafted the Clean Rivers report. He was referring to the state swimming standard of 126 instances per 100 milliliters.
River Authority monitoring shows bacteria levels tend to stay relatively low on dry days.
For example, on Aug. 22, a monitoring station at San Pedro Creek Culture Park read 59 instances per 100 milliliters, well below the swimming threshold. Also on Aug. 22, a station on the Mission Reach recorded only 15 instances per 100 milliliters.
On average, bacteria values for many of the impaired streams in the report hover around 185 to 200 instances, Lorea said. Bryant said the highest she’s seen is around 700.
A page on the River Authority’s website lists recent water quality tests for areas like San Pedro Creek, the Mission Reach, and some popular paddling spots further downstream.
“Those are doable numbers,” Lorea said. “Maybe not in my lifetime, but within a certain amount of time.”
Until then, there’s a way to find out if your favorite recreation spot is having a bad bacteria day.