SAN ANTONIO — The lack of rain has been a growing concern across Texas. The extreme heat is taking a toll on waterways in San Antonio.

Riley Perillo is from Buffalo, New York, and came to San Antonio on vacation. He had to stop by one of the top tourist attractions in Texas, the San Antonio River Walk.

“I think the boat tours and things are really cool,” Perillo said. “All the bars and stuff seem like a good time.”

Unknown to Perillo, the River Walk would look much different without a little help.

“That still has water flowing because we have saws reuse water being pumped into the river constantly,” Shaun Donovan said.

Donovan is the environmental sciences manager at the San Antonio River Authority.

“The water quality is pretty good right now,” Donovan said. “The water quantity is the big issue.”

The drought is affecting river flow. Shaun says there would be a visible problem if treated wastewater wasn’t pumped back into the city.

“The River Walk would quickly lose water and we wouldn’t be able to have barges going through the city,” Donovan said. “It wouldn’t be visually appealing. So that SAWS reuses water is vital to the economy of the city and the ecology of the river.”

Marine biology has always fascinated Donovan. He says the lack of rain is having the biggest effect on the river south of downtown.

“You’d see something all the way across to these rocks up here,” Donovan said. “So it’s probably six inches to a foot lower than typical.”

On top of low water levels, algae build up has become a growing problem.

“Algae can bloom and blossom out of control, which can have an issue like depleted amount of oxygen in the water for fish to breathe,” Donovan said. “That can cause those fish to get stressed and even die.”

More than 68% of Texas is in an extreme drought. Which leads to water evaporating. Donovan says the only solution is rainfall.

“Rain and cooler weather,” Donovan said. “That’s good for the river. That’s good for us as people.”