Below the surface of Granite Shoals’ water woes

The Granite Shoals water system has had a rough year, but relief could be on the way. The city has almost completed $7 million in upgrades that should remedy many of the issues with water quality, maintenance, and management.

Most recently, residents have dealt with discolored water coming from their faucets due to a murky Lake LBJ caused by flooding of the Llano River. In September, the city received a violation from the Texas Commission on Environmental Quality for exceeding maximum contaminant levels in its water. And a lightning strike to the pump system in July put the city on major water restrictions for weeks. 

Granite Shoals Utilities Superintendent Josh Hisey acknowledged that the water system needs work, but he painted an optimistic picture of the near future and addressed some of the problems over the past year and much further back.

“Most of the people we have out here in Granite Shoals have a bad taste in their mouth about water from way back in the day,” he said. 

According to Hisey, many of Granite Shoals’ water lines are old, some dating to the 1950s, and some residents might not know their home is tied into an old line or suffering from the effects of an ancient valve or dead-end line. The city has also been operating with a lackluster water plant since 2007, setting the system up for failure, Hisey said.

Hisey has supervised $7 million in upgrades to the water system since he started working for the city in 2020. Before coming to Granite Shoals, he spent 14 years with the Horseshoe Bay water department. 

Upgrades include a new water tower, a new clarifier, new software for monitoring the water system, new sludge lagoons, and a new disinfectant system. Voters approved the $7 million bond in 2019, but the economic and supply chain impacts of the COVID-19 pandemic dragged out the projects it was set to fund.

To understand the upgrades and the problems they’re solving, here is a rudimentary breakdown of how the Granite Shoals water system works:

• An intake pump draws water from Lake LBJ.
• Pretreatment chemicals are added with feedlines to disinfect and clarify the water as it is drawn into the system.
• The water enters a massive clarifier, where large particles are drawn out and sink to the bottom.
• Water leaves the clarifier and goes into filters, where it is made as clean as possible and disinfected again.
• Water leaves the filters and goes into clear wells, which store the clean, drinkable water until it is needed.
• Water leaves the clear wells and is pumped into the Blue Briar water tower.
• Water flows out of the water tower through distribution lines buried across the city and connected to homes.

Hisey noted that, of the major system upgrades, the new clarifier and disinfectant system should have the greatest positive impact on water quality. 

Granite Shoals’ old water plant, built in 2007, only had one clarifier to hold disinfected water from the lake. Once in the clarifier, large particles and debris in the water sink to the bottom due to an added coagulant. The water then ideally leaves the clarifier free of the large particles before it reaches the filters.

Only having one clarifier is a major design flaw, according to Hisey, because it could never be turned off for maintenance or cleaning. He explained that a layer of sludge at the bottom of the clarifier is normal, but because no cleaning or maintenance has been done in 15 years, that sludge layer has risen too high and is likely contributing to the poor taste and odor in city water. 

With the completion of a second clarifier, which should be online by mid-December, the city will be able to shut down the old one, clean it, and drastically improve the water’s palatability.

The TCEQ violation Granite Shoals received in September cited the city for exceeding maximum contaminant levels of trihalomethanes, chemicals formed from a reaction between chlorine used in the disinfection process and organic material in the water. The safe threshold set by the U.S. Environmental Protection Agency is 0.080 milligrams per liter. The city’s levels were recorded at 0.088 milligrams per liter in September.

Granite Shoals has switched its disinfection process from a free chlorine gas system to a chlorine dioxide system, which should drastically reduce the presence of trihalomethanes in city water, Hisey said. It should be said that chlorine, in some form, is used in nearly all water treatment processes around the world. The TCEQ violation did not result in any fines, but it noted the water would be tested again after the new clarifier is built, which should further reduce the presence of trihalomethanes in the water.

“Over the years, we’ve developed a long list of violation notices from the TCEQ — in the last eight years at least — for disinfection byproducts,” Hisey said.

The city’s most recent issues with water clarity due to the flooding of the Llano River in October were a result of poor timing and revealed a hole in its water treatment capabilities.

“The issue was that we just didn’t get back online fast enough with our chemicals to dose the 100-NTU water coming into the plant,” Hisey said.

NTUs, or nephelometric turbidity units, measure the amount of particles in water and its clarity. According to the World Health Organization, the turbidity of drinking water should never exceed 5 NTUs. While the water that reached Granite Shoals homes after the flood was below that level, at 0.28 NTU, it still took a toll on the system to process out so much material. 

Even with the majority of large particles removed from the water, many homes had green, brown, or yellow water coming from their faucets.

“It makes me not want to take a shower,” resident Tara Walker told DailyTrib.com on Nov. 17. “I definitely don’t want to cook with it.”

Green water was pouring into Walker’s bathtub on that day, and since at least August. She said the problem intensified after the river flooded.

Hisey tested the water going into Walker’s home on Nov. 17 and produced a photo showing clear water in a cup from the line feeding into the house. He explained that the discoloration could possibly be a problem with the home’s internal plumbing.

“If you have an issue and you don’t contact us or contact the city, we can never get out there and solve the problem and fix it,” he said. “If they do call us in, we’re more than happy to get out there and see what we can do, if it’s on our end.”

Even with Granite Shoals upgrading its water system, the current treatment process won’t change discolored water. Hisey offered an analogy explaining the difference between discoloration and turbidity, saying it’s like throwing a handful of dirt in a bucket of water and putting tea bags in the other. The dirt will sink to the bottom and can be filtered out, but the color left from the tea cannot be removed.

Removing discoloration from the water would require the city to switch its process to reverse osmosis filtration, which Hisey said would cost at least another $7 million in upgrades.

Contact the city of Granite Shoals about water issues at 830-598-2424 or citysecretary@graniteshoals.org.

dakota@thepicayune.com