Columbia's aging McBaine Water Treatment Plant is on the verge of a much-needed upgrade

The aging McBaine Water Treatment Plant, with equipment nearing the end of its usable life, needs an upgrade.

The City of Columbia's project to improve the plant is budgeted at about $21.5 million.

This includes final engineering design from HDR Inc. and about $20 million in construction costs paid through a future bond sale as part of a $43 million bond issue approved by voters in 2018 for capital improvements to the water system.

Price volatility could impact how a construction bid package is formed. Material costs are starting to come down, however, said Ryan Saffels, HDR associate vice president and project manager.

The city has tried to put as much forethought into costs as it can, said Shawn Carrico, Columbia Water and Light engineering supervisor.

"We do hope things continue to come down," he said Monday. "We're finalizing the 90% cost estimate. We can discuss that at a future meeting when we come back for authorization to bid the project, provided we move forward tonight."

The bulk of the work involves stainless and electrical materials, Carrico added.

As the city looks at bid alternatives, Mayor Barbara Buffaloe hopes the city will identify further funding availability to provide additional money to cover alternatives or even additional improvements. There are grants for which the city has applied and will learn the outcome in mid-October, Carrico said.

Even with the price volatility, HDR believes it still will meet the original intent of the project presented to voters, said Trent Stober, HDR vice president and project principal, who also is a Columbia resident.

The Columbia City Council, following a public hearing Monday night, authorized the city in a 5-1 vote to proceed with finishing out the design plan for improvements and start the Missouri Department of Natural Resources permitting process.

The design was 90% complete as of Monday.

First Ward council member Pat Fowler voted in opposition over concerns that even with upgrades, there still likely will be cancer-causing disinfectant byproducts in the city's water system. The DNR permit would close off an opportunity for design strategies to further reduce or eliminate these byproducts.

Second Ward council member Andrea Waner is on maternity leave and did not vote.

Fifth Ward council member Matt Pitzer, who voted in favor, wanted clarification on why it took until Monday to hold the public hearing, when the original timeline was to have the project underway in fiscal years 2021 and 2022.

The delay was due to the HDR service agreement and the extra time used to develop the project design since the bond sale has not yet happened, Carrico said, while recognizing there was a delay in getting the engineering contract in place.

The ideal timeline to put out the construction project for bid after design and DNR permitting is end of year, said Dave Sorrell, Columbia utilities director.

Construction then would likely start next summer if the ideal timeline occurred.

Project timeline; treatment upgrades

Plan finalization by HDR will take at least another two months, and the DNR permit process will take anywhere from three to six months to complete. After that, the project can go out for construction bids, followed by up to two years of construction.

The upgrades will get the McBaine plant back to treating 32 million gallons per day, or MGD, improving upon its current 24 MGD limited by equipment reliability issues first identified six years ago, Stober said.

Aging infrastructure will be replaced, along with improving treatment performance and preparing for future treatment enhancements, such as a granular activated carbon contactor, or GAC, he added.

A GAC would have an added construction cost of $47 million and an annual operational and maintenance cost of $4 million to $5 million based on 2020 cost estimates. Such a system would allow for free chlorination as a secondary disinfectant to prevent biological growth in the city's water distribution system.

The project is planned to modernize the McBaine system and aims to reduce water treatment disinfection byproducts, which can cause cancer. Some are regulated, while others aren't, Stober said.

The city currently uses a mixture of chlorine and ammonia, or chloramine, for its primary and secondary disinfectant. When the treatment plant previously had used free chlorination without a GAC, its disinfection byproducts were exceeding regulation amounts, Stober said, answering a question from Pitzer.

The exceeding of regulatory amounts was due to the plant increasing its treatment and distribution system capacity over the years, Carrico added. This was in 2008-09, which led to the reevaluation of what disinfectants are used, he said.

Other regulatory changes also led municipal water systems to adopt chloramines, said Eric Berggren, HDR vice president.

Treatment performance will improve even without a GAC for now, Stober said. Plan improvements include replacing aerators, softening basin mechanisms, filtration components, finished water pumps, chemical feed systems and instrumentation.

"Before implementing a (GAC), we recommend to assess where we are at after these improvements are made," he said, noting future addition of a GAC system would be an extra piece to what already is in the improvement plan. "Everything we pay for now we'll be able to use into the future."

Of what is feasible under the current budget, HDR will "replace every major treatment process at the plant," Saffels said, noting this includes additional monitoring for water quality parameters and automating of systems.

Community comments

Chief among comments from community members Monday was that much of what is being done now is coming far too late and the treatment plant needed review at least 10 years ago.

There is an opportunity to put solar panels on the facility to help offset some operational costs, said one speaker, who also was concerned if upgrades would address micro- and nano-plastics as well as per- and polyfluoroalkyl substances — known as PFAS.

Julie Ryan, co-founder of the CoMo Safe Water Coalition, said she should not have to have a whole carbon filtration system in her home to have safe drinking water.

She also is concerned over the decade of consulting costs and no substantive action.

"There has been no accountability for this plant being de-rated and now we are spending a lot of time having to restore capacity because no one was held accountable when it was de-rated," she said, adding a GAC would address changing EPA regulations and chloramines. "Rate payers spent the money to fund the drinking water planning working group that said remove chloramine, and it's not getting done."

David Switzer, member of the Water and Light Advisory Board, spoke on his support of city staff and the work done by HDR.

"I support the treatment plant upgrades. I think they are a good thing. I also think activated carbon is a good thing." he said. "If the city were to invest in that, I would be very excited.

"That's not a staff decision. They can give you the information that says (the costs). These are experts, and we should challenge them, but it is not healthy to assume bad faith in terms of actions from consultants or staff."

Charles Dunlap covers local government, community stories and other general subjects for the Tribune. You can reach him at cdunlap@columbiatribune.com or @CD_CDT on Twitter. Please consider subscribing to support vital local journalism.

This article originally appeared on Columbia Daily Tribune: McBaine Water Treatment Plant upgrade plan moves forward