The city hopes to begin the bid process for repairs to the McBaine Water Treatment Plant later this year as questions linger about treatment options.
Repairs to the McBaine Water Treatment Plant have been in the design phase since August. Project engineer Shawn Carrico said “there’s been a fairly long process” for design, but that it is “90%” finished.
The city appropriated $23 million for the project through a bond issue for water treatment projects in August 2018. While the pandemic did play a role in slowing the project, the delay between the passage of the bond measure and the start of the project was largely due to city procedures.
Following the passage of the bond issue that is funding the project there are a number of steps that need to be done to secure and allocate funding. These include the issuance of bonds, rate increases and the appropriation of funds, according to Carrico. All of these steps require some form of approval from City Council and review by the Water and Light board, he said.
Water production manager Kevin Wiggins explains the water treatment process Dec. 16 at the McBaine Water Treatment Plant. The water flows into the primary clarifier, where it is mixed with lime to remove impurities.
The city contracted HDR Consulting, an engineering firm based out of Omaha, Nebraska, to design the project.
The improvements at the city’s water treatment plant have become the subject of controversy, as the city wants to focus on routine repairs and replacements, while some groups have called for more comprehensive changes to the city’s water treatment system.
Some have called for changes to the filtration processes used by the city as well as changes in the chemicals that are used for disinfection. These changes would improve the city’s water quality but would also present much higher costs for the city. City officials to date have been resistant to implementing the more expensive changes in favor of keeping rates and costs low.
This will be the third time the plant has undergone changes since its construction in 1970. There have been two expansions of the plant since it’s construction but the majority of the original components are still in service today, Carrico said.
The proposed renovations are intended to increase the plants production to its full potential of 32 million gallons a day, a point made last week by City Manager De’Carlon Seewood in his State of the City address.
“I prefer to say that our plant has a firm capacity of 24 (million gallons per day) because there is always something that has to be done,” Carrico said.
Sludge removed from the water during the filtration process contains oxidized iron, which gives it a rich, orange-brown color. While the water continues its treatment journey on to primary and secondary basins to remove any additional unwanted particles, the sludge is flushed from separate basins to outside lagoons to dry and solidify.
The project is planned to replace a number of components for the plant, according to Carrico. He said that some components are “at the end of its useful life” so “it’s becoming more costly to repair items than it is to replace them.”
Carrico said that the city has to “sell our second round of bonds that was approved in 2018,” which he said would likely be associated with a rate increase for residents.
The 2018 bonds were split into two sales. The first bond sale occurred in May 2019 for $15.2 million and funded the design phase of the plant’s renovations, among other water system improvements throughout Columbia, according to city spokesperson Sydney Olsen.
The second round of bonds for $26.9 million will cover the construction and repairs at the plant and additional system improvements, Olsen said.
However, some community activists have called for more changes to be made to the plant.
COMO Safe Water Coalition, founded in 2016 by Julie Ryan and Marie Brown has called for changes to the methods that are currently used to treat and disinfect water at the plant.
“Our big ask was: remove the chloramine,” Ryan said.
Co-founders of the COMO Safe Water Coalition Julie Ryan, left, and Marie Brown, right, meet in December 2016. The coalition was founded in 2016.
The disinfection method currently used by the city is a mixture of two chemicals, chlorine and chloramine, which are both commonly used at water treatment plants.
The process works like this: first, water is disinfected with chlorine, but chlorine on its own is not always enough, since chlorine can bind with organic compounds like waste products to create harmful byproducts that are known as total trihalomethanes, according to the Environmental Protection Agency.
To amend this, ammonia is added to the chlorine to form chloramine, which acts as a secondary disinfectant down the line, according to the city’s website. However, clean water advocates have recently pointed out some disadvantages in the use of chloramination, such as nitrification, according to the EPA.
“So we need some enhancement,” Ryan said. “We need a treatment that would help us get to a point where we don’t have to use chloramine.”
COMO Safe Water Coalition has proposed that the city use what is known as granular activated carbon (GAC) in the filters as a preemptive step before disinfection. What this would do is remove the waste compounds that chlorine can negatively react with removing the need for chloramine disinfection and a return to what is known as free chlorine disinfection, according to EPA studies.
Chlorine is considered to be a more effective disinfectant, but it is more reactive than chloramine which is why they are often used together, according to the EPA. Chloramination, however, presents its own issues such as the possibility of nitrification, the EPA says.
A city PowerPoint presentation states that the city conducted research and a cost-benefit analysis on the use of GAC filters and found that, in their opinion, they would be far too expensive to implement at that scale.
“Another factor involved with that is always rates,” Carrico said.
In the alternative study conducted by the city’s consulting firm HDR, they stated that the implementation of GAC filters would cost the city $39.7 million to $58.4 million along with a $2.7 million to $4.2 million increase in annual operating costs.
The city attributed the high costs of implementing GAC filters to the changes they would have to make in their treatment processes to use them as well as the costs of replacing filters whenever the media in the filters is spent.
“We looked very heavily at various combinations of granular activated carbon and biofiltration,” Carrico said. “Adding a secondary set of granular activated carbon filters did prove to be beneficial. However, it was at a very substantial cost. Our process right now is a very lean, very affordable process.”
Ryan and Brown, however, believe that the cost is justified.
“We just tried to meet regulations with whatever tools that we have,” Brown said, “and it’s not necessarily what’s best for public health.”
Ironically, in October 2021, the city was cited by the Missouri Department of Natural Resources for violations under state regulations because the levels of chloramine in the city’s water fell below the prescribed limit of 0.5 milligrams per liter for too long. This is not the first time Water and Light has been cited with violations, according to previous Missourian reporting.
Kevin Wiggins, water production manager, gives a tour of the McBaine Water Treatment Plant. The pipes transport water to the aerators, where it is mixed with air to oxidize impurities in the water such as iron and manganese.
At the City Council meeting on May 2, Ryan said that this violation points to nitrification occurring, according to experts she spoke with.
According to the EPA, nitrification in water treatment is the process of certain bacteria breaking down the ammonia in chloramine, which has many adverse effects, including disinfectant depletion and increased bacterial growth.
Brown hopes that Ryan’s words got through to the council members.
“It’s hard to tell what they’re thinking,” she said. “I’d like to hope they took it home and I think that they’re concerned about the situation.”
Carrico said that future improvements are being looked at for the plant, but nothing there are money factors which would impact future decisions.
“So we do have some folks that are pushing us to do more with the plant and improve the water quality aspects there,” he said. “At this point that timing is uncertain. We do have a future project earmarked in the budget, although it’s unfunded at this point in time.”
Ryan and Brown, in addition to their request for the removal of chloramine in disinfection, said that they were frustrated with the city’s unresponsiveness to them and other residents, but said that nothing will change unless people keep speaking up.
“You don’t get the answer to the questions you don’t ask,” Brown said.
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