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Success! How Two Cities Updated Aging Water Treatment Plants

By Deborah Lynn Blumberg

Two public works staff
Tonka Bay Public Works Superintendent Robin Bowman, left, and City Administrator Kathy Laur led the city’s water treatment renovation project, which was done with the help of a low-interest loan. PHOTO BY ERIC HAUGEN

In the spring of 2017, when Tonka Bay went through its annual water treatment plant inspection, the Minnesota Department of Health (MDH) delivered some heavy news. The city could no longer wait to rehabilitate its 1970s-era plant, which was hobbling along with old equipment.

“We knew it needed to be done soon,” says Tonka Bay City Administrator Kathy Laur. “But they said, ‘Time’s up; you’ve got to do it now.’”

Like many cities, Tonka Bay had put off the project for as long as possible given the major expense. It was the same for the City of Pipestone, nearly 200 miles away near the South Dakota border, which found itself in a similar position two years prior.

For over a decade, officials in Pipestone, a city of 4,000, knew they would have to replace the city’s 90-year-old plant so it could better reduce chloride levels in the water. At high levels, chloride can be toxic to certain aquatic species. The city also needed to reduce the concentration of gross alpha emitters in its drinking water to protect public health.

“The city had been aware of these issues for quite some time,” says Pipestone City Administrator Jeff Jones.

Clean water is one of the most important services cities provide, yet it’s not cheap or easy to deliver. Upgrading water treatment facilities is a major endeavor, and cities — especially smaller ones — often struggle to find funding. Yet, as both Laur and Jones found, there’s funding available to take antiquated plants into the modern age.

Evaluating and paying for needed upgrades

In addition to the city’s 1,600 residents, Tonka Bay’s water treatment plant provides water to six homes in the neighboring community of Shorewood, plus the area police and fire departments, and the Shorewood Public Works Department.

The city moved quickly on the MDH recommendation to complete an engineering evaluation of its plant. The plant’s age was a major concern and presented challenges when it came to maintaining consistent water quality.

Three city of Pipestone staff in the water treatment plant
Pipestone City Administrator Jeff Jones, left, Water Superintendent Joel Adelman, center, and Water Foreman Justin Powers were instrumental in planning the city’s new water treatment plant. PHOTO BY ERIC HAUGEN

In November 2017, the city hired design and consulting firm WSB to evaluate the plant and water tower. The following February, WSB presented its report to the City Council. “That got the ball rolling,” says Robin Bowman, Tonka Bay superintendent of public works. “The equipment was just getting so old that it no longer was functional.”

Council members voted to move forward with renovations. The city’s timeline was too short to apply for grants, but Tonka Bay was able to secure a $1.9 million low-interest loan from the Drinking Water State Revolving Fund (DWSRF) administered by the Minnesota Public Facilities Authority and MDH. The 1.9%-interest loan covered the full cost of the project.

To help repay the loan, the city raised its water rate by 37%, passing on a portion of the cost to residents. The city prepared residents ahead of time by including information about the rate hike on utility bills before the increase as well as on the city’s website, in its newsletter, and on social media. “We had very little pushback,” Laur says.

Plant rehab = good water quality

One of the first areas Tonka Bay addressed was its Lime Softening Feed System. Tonka Bay’s central water treatment plant uses lime for softening instead of salt. WSB ranked replacing the water plant’s Lime Softening Feed System as the highest priority, and the city moved to design improvements in the spring of 2018.

Construction kicked off the following fall, and the project concluded in the spring of 2020, with delays due to COVID19. Improvements included removing the old lime slaker equipment and adding a new lime tank slurry system.

The water plant’s clarifier was reconditioned, and unnecessary equipment removed. Almost all of the plant’s valves were replaced, as was a hydropneumatic tank used as a backup to the water tower.

Renovations also included painting the plant, labeling pipes, and installing a new roof system and generator, among other improvements. Equipment has a 20-year lifetime.

The plant also upgraded to a SCADA (Supervisory Control and Data Acquisition) system that allows Public Works operators to monitor the plant remotely. “It’s the brain of the plant, and simplifies things for Public Works quite a bit,” says Laur. And, more importantly, “The water quality is now very good.”

Communicating with residents

Pipestone also got its water plant project underway with a water system evaluation done by city engineers in 2015 after the Minnesota Pollution Control Agency (MPCA) told the city it had to address its chloride issue by 2018 or face fines. The city held a public meeting for residents and invited MPCA officials and state Sen. Bill Weber.

“It was important that we made residents aware of the reasons why we needed a new facility,” and the need for an eventual increase in rates, Jones says. “Knowing we had a gross alpha issue, too, we looked for a system that would reduce or eliminate both [problems], and that’s what we ended up doing.”

The city’s engineering firm, Bolton & Menk, helped Pipestone draw up plans for a brand-new water treatment plant. Engineers and the city’s water supervisor toured half a dozen nearby plants, weighing their options.

Ultimately, they decided on a lime softening approach for Pipestone. “They did an excellent job in their due diligence,” Jones says.

The new plant was also designed to reduce the hardness of water leaving the plant, eliminating the need for residents to have water softeners at home, which contribute to chloride concentrations at the city’s wastewater plant.

Planning for grants

In 2016, city officials moved to get Pipestone’s project on the MDH Project Priority List (PPL), a list of proposed drinking water infrastructure projects from cities across Minnesota. To be eligible for a loan through the DWSRF program, cities first have to add their project to the PPL.

Pipestone water treatment plant
Pipestone received an Aquarius Award for excellence in the financing and construction of this new water treatment plant. PHOTO BY ERIC HAUGEN

Then, Pipestone solicited bids. Still two years out from MPCA’s deadline, the city also had plenty of time to apply for grants to fund the project. Jones and others working on the project secured a point source implementation grant of $7 million from the state, in addition to a DWSRF loan of $8.4 million at a low, 1.13% rate to cover the entire $15.4 million project.

Funding came through in July 2017, and construction kicked off immediately. Two years later, the new facility started treating the city’s water. In addition to the new water treatment plant, the project included installing raw water mains and a new well. The plant has a SCADA system, allowing staff to run the plant remotely, and it’s projected to last for the next 40 years.

Most importantly, the new plant has reduced the chloride concentration and gross alpha levels to below detection in Pipestone’s water. Softening water at the plant also led many residents to quit using their water softeners, resulting in real savings.

“It’s the biggest project I personally have been involved in,” says Jones. “It was a needed project and, overall, it went very well.” Pipestone, too, had to raise water rates to pay down the debt incurred with the project. “Local residents are bearing a big part of the cost,” Jones says.

From 2017 to 2020, water rates essentially doubled. But residents had plenty of warning. “Folks have been good about it,” he adds. “They like the taste of the water, and they like not buying water softener salt and lugging it down into the basement.”

Businesses have also benefitted. Many — including local car washes, a nursing home, and a meat-processing plant — previously spent significant funds to soften the water. “Those folks saw lots of savings, too,” says Jones.

Pipestone’s project received an Aquarius Award last year from the DWSRF program for excellence in innovative financing, problem solving, and protection of public health.

Clear objectives are key

To other cities looking to upgrade their water treatment plant, Laur says to prepare well ahead of time, which gives you a better chance of receiving a grant. She also recommends spending adequate time going over plans with city engineers before bidding, and then with a contractor before starting work to confirm or delete items that need to be upgraded.

In addition, cities should “make sure they’re clear on what their objectives are and keep coming back to them during the renovation to see if it’s still what they intended when the process was started,” she says. “Things can change, and frequently do, during the renovation of an existing, aged facility.”

Jones stresses the importance of hiring an engineering firm with similar experience in their portfolio and communicating often with residents. You have to let residents and local businesses know what the city’s doing and why it’s important.

Keeping the water plant up to date “allows businesses to develop and provides for the needs of the residents,” Jones says. “Quality drinking water is the foundation of a community’s sustainability.”

Deborah Lynn Blumberg is a freelance writer.