SAN ANTONIO - A KSAT-12 Defenders test of the San Antonio River flowing out of the zoo shows a new treatment plant installed there is working to disinfect the water.
However, a test of water downstream on the River Walk showed elevated E. Coli compared to previous results.
April Alcoser of the city's Public Works Department said there was one major source of contamination at the zoo.
"We're talking about all resident animals that are there and nonresident animals," Alcoser said.
The Defenders tested the San Antonio River in August 2013 in three places: upstream from the zoo, downstream from the zoo and at the River Walk.
For years there have been concerns that the bacteria count at the River Walk made the river potentially dangerous.
Those concerns came to a head when Dallas Mavericks basketball team owner Mark Cuban years ago criticized the water quality in the river in highly publicized comments.
The recommended limit for E. Coli in recreational water is 394 colony forming units per 100 milliliters of surface water.
The San Antonio River is not considered a recreational body of water in that swimming is not allowed.
However, tests found low E. Coli counts upstream from the zoo in August of 2013 of 272 cfu.
Downstream from the zoo the E. Coli level shot up to 12,600 cfu.
Much of that reading is attributed to animal and bird waste from the zoo washing into the river.
On the River Walk the reading declined to 1,550 cfu.
In late 2013, construction on a water treatment plant downstream from the zoo was underway.
Alcoser said the goal was to disinfect water coming out of the zoo with ultraviolet light.
"We're expecting that once the treatment facility is in operation that it's going to significantly lower the bacteria levels," Alcoser said in 2013.
After months of delays the plant finally began operations at the end of May 2014.
The Defenders once again tested the river water on June 5, 2014, through an accredited lab.
Tests were done upstream from the zoo, downstream from the zoo and at the River Walk.
The test found the E. Coli upstream from the zoo was much higher than before at 1,870 cfu.
Downstream from the zoo, however, it was drastically reduced from the 12,600 cfu reading from August 2013 to 1,180 cfu, evidence that the water treatment plant was working to disinfect the water flowing out from the zoo.
The big surprise was the River Walk reading, which was the highest of all three at 5,710 cfu.
At the River Walk, tourists and locals weighed in on whether it is important to keep the river clean.
Helen Gonzales works at the Hard Rock Café on the River Walk and said she has not heard any complaints.
"No! Nobody cares about touching the water," Gonzales said. "Why would you care? Everyone says that they love it here. I mean people come from all over: France, Spain, Brazil."
Tourist Jennifer Shallet from Abita Springs, Louisiana, felt the same way.
"It doesn't matter to me," Shallet said. "I mean we're taking a boat ride. We're not going swimming in it. I come here for the history. It doesn't bother me."
Enid, Oklahoma visitor Kourtney Janes, however, rated clean water moderately important on a scale of one to ten.
"Probably at least a five or a six, just to know you're going to a clean place and especially, you know, being a visitor," Janes said.
Public Works is now looking into why the latest test of water upstream from the zoo and downstream at the River Walk tested higher for E. Coli than previous tests.
Alcoser did send this email in regard to that: "The UV Treatment Plant has been very effective at reducing bacteria levels discharging from the zoo. The timing of the egret population and other wildlife, such as ducks could have affected the increase levels of bacteria above the zoo and within the River Walk. The time of day, temperature and turbidity (sediment) could have also effected the bacteria levels."
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