Leaky pipes and irrigation runoff responsible for up to 90% of Austin creek's flow

If it weren't for the leaky pipes, Austin's Waller Creek would be a trickle of its current self.

AUSTIN (KXAN) -- If it weren't for the leaky pipes, Austin's Waller Creek would be a trickle of its current self.

Instead, the Bald Cypress Trees surrounding it reach out to dip their large extensive roots into the water, giving them a reliable source of water that's helped turn the creek into a lush shaded oasis running through the heart of the University of Texas at Austin campus.

Meanwhile, water cascades down the rock surrounding the creek, primarily runoff from campus irrigation.

This combination of leaking drinking water, waste water, and irrigation runoff makes up to 90 percent of the creek's flow, according to a new study by University of Texas Professor Jay Banner.

"Every city in the world suffers from it, so that's a big negative," he said. "But a positive on the other hand, was that these trees actually are doing better during droughts, so it's making them more resilient."

To reach that conclusion, Banner and his team compared the growth records of the Cypress Trees along Waller Creek, with those growing on Onion Creek about 12 miles away.

With the help of students, the team pulled out wood core samples from the trees and look at the rings, with thicker rings reflecting wetter times and strong growth and thinner rings reflecting dryer times and little growth, according to the study.

The results showed that even during times of extreme drought, the trees on Waller Creek showed steady and healthy growth, whereas the Onion Creek trees had thinner rings, reflecting weaker growth.

"At the end of the day, the negatives will still far outweigh the positives," Banner said. "Even though there's a benefit, we have to consider, do we want to engender this?"

Banner said determining whether or not to fix the pipes is a decision left for the UT and Austin Water Departments.

However, he hopes his research can be used to help make better decisions when planning for future growth.

"We're pumping a lot more water around town just to get the amount of water that we need," he said. "Can we plan for the future and actually prevent those costs from coming up, and, at the same time, perhaps provide this positive consequence by having a more controlled water network system where we can deliberately create the largest drip irrigation system in the world?"