By Karen Gleason
The 830 Times
(Story about tour is here.)
City administrators on Monday led a tour of the city’s wastewater facilities, showing that infrastructure changes to allow larger system capacities may have to be made before housing growth on the city’s north side can continue.
City Manager Shawna Burkhart and City Public Works Director Greg Velazquez led the tour.
Participants included Mayor Al Arreola, Mayor Pro-tem Jim DeReus, Councilman Jesus Lopez Jr. and Councilman Randy Quiñones, as well as Val Verde County Judge Lewis G. Owens Jr., County Commissioner Pct. 1 Kerr Wardlaw, County Commissioner Pct. 2 Juan Carlos Vazquez and County Commissioner Pct. 3 Fernando Garcia.
city’s wastewater treatment plants during a tour of the facility on Monday. Joining the
city manager were, from left, Jaime Kypuros, engineer with Tetra Tech, the city’s
engineering consultants for the improvements; Adrian Quiroz, the city’s wastewater
superintendent; City Public Works Director Greg Velazquez and Peter Ojeda, city
marketing and communications director. (Photo by Karen Gleason)
Also attending the tour were Juan DeHoyos and Jesus Hernandez of Deroga LLC, developers of a 60-acre property that has been temporarily paused because of sewer capacity concerns; Jaime Kypuros, an engineer with Tetra Tech, the city’s consulting firm on wastewater system improvements; a representative of Texas Rep. Eddie Morales’ office, as well as a private citizen and her two children and members of the local media.
Tour participants met in front of the terminal building at the Del Rio International Airport then drove separately to Nicholas Street on the northwest side of the airport to look at an uncovered manhole.
Velazquez explained the smelly stream of murky brown water that could be seen flowing inside the manhole was coming from the Edwards Street lift station on the city’s north side.
“This picks up everything from Edwards, all of Ceniza (Hills), all of Buena Vista, the school, all up here on Mary Lou, all of the north side, comes through here,” Velazquez said.
He told the group the city’s sewage flow “splits” in the area of Walmart, with sewage north and west of the store traveling to the Silverlake Wastewater Treatment Plant on Frontera Road. All the sewage from east and south of Walmart eventually ends in a wastewater treatment plant on Guyler Lane.
The city is planning a two-phase improvement called the Northside Sewer Outfall, a $30 million project aimed at increasing the sizes of the pipes carrying wastewater to the city’s Silverlake plant.
Adrian Quiroz, the city’s wastewater superintendent, said wastewater flows typically peak twice daily, from 8 a.m. to 9 a.m., then again from 7 p.m. to 8 p.m.
“The issue is . . . the amount of wastewater that’s accumulating in a line that needs to be upsized,” Velazquez said.
Councilman Jesus Lopez Jr. asked if the line at Nicholas is an 18-inch line and was told that it is.
“And we’re going to go to a 30-inch line?” Lopez asked.
“We’re going to go to 36 inches,” Velazquez replied.
Velazquez then introduced Tetra Tech engineer Jaime Kypuros.
After Kypuros answered some questions from two developers who joined the tour (separate story here), County Judge Lewis G. Owens asked, “The first phase is to try and increase the size of the sewer line, but will the (Silverlake) wastewater treatment plant handle it?”
“Based on the study that has been done, the feasibility report, the current wastewater plant can handle that impact, yes it can. Now there’s some modifications that are going to be done, based on a report that we have, a study, in order to work on oxidation ditch 1 and oxidation ditch 2 and possibly raise up the walls, but currently, yes, we can handle it,” Velazquez said.
“So the line itself, because you’re going to double it, the wastewater treatment plant, again, is going to be able to handle that amount of volume?” Owens asked.
“That’s correct,” Velazquez replied.
City Manager Shawna Burkhart added the improvements on the first oxidation ditch at Silverlake will probably cost about $4 million and have already been financed. She said improvements to the second oxidation ditch will probably cost $4 million more, and the city will have to find the money.
“Ditch 1 (improvements) have been financed, . . . and we will be doing that work as soon as possible,” she said.
The tour’s next stop was on Brewer Drive, at a manhole that will be the end point of the first phase of the Northside Sewer Outfall project. That project aims to increase wastewater flow capacity from burgeoning development on the city’s north side, increasing the size of pipes from the existing lift station on Edwards Street in the Del Rio Hedges area north of Walmart all the way south to the Silverlake plant.
Wastewater department workers lifted a manhole cover on Brewer Drive, and Velazquez invited tour participants to look down into the manhole.
“As you can all see here, the line is completely full,” Velazquez said.
The tour’s last stop was at the Silverlake Wastewater Treatment Plant on Frontera Road.
Burkhart first led tour participants to the large concrete influent box on the north end of the facility.
“This is where your inflow comes in. . .You’ll see that the pipe (going into the influent box) is about half-full, and that’s because this pipe is a 24-inch pipe, not an 18-inch,” Velazquez explained.
He continued explained how the plant works and the capacities for which it was designed.
From the influent box, wastewater is pumped into one of the plant’s two oxidation ditches, sometimes called “racetracks” because of their long oval configuration.
Velazquez said the city is planning to enhance the oxidation capacity of the two ditches, which will allow for faster breakdown of the organic waste in the water.
Burkhart reiterated the city currently has the funding to make improvements to one of the plant’s two oxidation ditches.
“We have to get the second one funded,” she told the group.
She added the improvements to each ditch would cost about $4 million.
Burkhart told the group. “Sewage is 99 percent water, 1 percent solids, so when you get into these racetracks, that’s where the bugs (bacteria) are eating down on the solids. So, once it goes to the clarifier, which we’ll see here in just a moment, it has a big squeegee on the bottom, and that squeegee moves in a circle, and it takes usually about 24 hours, so once the solids fall out, they (form) what’s called a sludge blanket.
“Once that sludge blanket gets to a point that they push it into a hole in the bottom of the clarifier, it gets pumped back to the head works or it gets pumped off to the drying beds.
We’re not going to be able to sustain this plant like this for very much longer, because we will have to have sludge presses because we are way too big for drying beds.
“It takes way too long to dry the sludge, so we need to eventually gravitate to a sludge press that presses the water out, and that’s captured and that water is treated, so that’s the basic notion of this,” Burkhart said.
As the tour of the plant continued, Quiroz told tour participants one of the “biggest issues” facing the plant is the amount of flushable wipes that end up in the plant.
“A lot of people don’t understand that flushable wipes do not break down. They are flushable, but they do not break down. I think that’s any wastewater plant’s biggest issue,” Quiroz said.
Quiroz also told the group improvements and upgrades to the city’s wastewater treatment plants are included in a master plan for the facilities.
“We have an engineering feasibility report, we have a breakdown, pretty much a master plan, of upgrades we need to do within a certain time frame. We have a five-year, 10-year, 20-year, up to a 50-year CIP (capital improvement plan). We’ve just got to make sure that we stay on track and secure funding and keep following it,” Quiroz said.
He said among the improvements planned at the facility include the addition of two more aerators to agitate the wastewater and replace the existing brush aerators with disc aerators, which are more efficient.
He said the same improvements are planned for the second oxidation ditch.
As the tour drew to its close, Burkhart said, “That’s why I’ve said, let’s not concern ourselves with the small projects that are not relevant to building a city. We have to maintain our water and sewer infrastructure.”
She said, “The only time you will see me as city manager absolutely blow budget is when this sewer plant goes down or when our water plant goes down. So when (Greg Velazquez) tells me, ‘I have two rotors out of three down,’ we got problems, because we can’t keep the (beneficial) bugs alive if we’re not giving them oxygen, and now it’s a health and safety issue for the community, so if there’s ever a time I ask for a ratification, it’s going to be on a sewer plant.
“This is the most critical function of what Greg does. That and providing water,” she added.
At the end of the tour, Burkhart thanked everyone for attending and noted, “We appreciate everybody’s attendance and participation. We hope that we’ve given a little education on our sewer system and we really do appreciate your time coming out tonight.”
The writer can be reached at delriomagnoliafan@gmail.com.
