New RPU water source likely to come with added cost for access and treatment

ROCHESTER — Rochester Public Utilities’s director of water service isn’t ready to tap surface options for the city’s future drinking water.

“I’m still optimistic that we will find a ground water solution,” said Todd Blomstrom, who also serves as RPU’s assistant general manager of operations.

The city-owned utility is roughly one year into researching future water sources after the Minnesota Department of Natural Resources banned the city from digging more wells to tap the Jordan Aquifer until other water sources were studied.

“It has been a very stable source for Rochester for 100 years,” Blomstrom told the Rochester City Council on Monday.

He said the city’s newest well was drilled in 2024 and current supply meets the anticipated demand for years to come.

While some council members cited the news as disturbing, Blomstrom said it’s not a crisis.

“There is a solution,” Blomstrom said..

The DNR ban came with the state’s approval of RPU’s 2024 well, and Blomstrom said he understood the concerns, noting other parts of the state have seen problems emerge with growing water needs and limited resources.

A local water system master plan is being developed with $1 million in contracts, and Blomstrom said it’s too early to predict the results, since initial steps have revolved around gathering information and projecting future needs through 2065.

However, he said any change in the water supply is expected to come with added costs for RPU customers.

The city’s 2024 well cost roughly $25 million, and Blostrom said drilling wells into deeper aquifers will require added expense, as would tapping surface water sources.

Either option will also likely require added treatment facilities.

Blomstrom said RPU’s current water supply falls within state guidelines with minimal treatment, but a new source is likely to require a dedicated treatment facility, especially with the expectation of new state standards, since safe drinking water isn’t likely to be found in surface water or in other aquifers, which would prompt the city to build a treatment facility.

“First and foremost is water quality,” he said. “We have to ensure the water we’re producing for customers is safe and that it is compliant with all state and federal regulations.”

While the city’s water for the Jordan Aquifer meets state standards with minimal treatment, Blomstrom said deeper aquifers tend to see higher levels of contaminates that need to be removed.

“The idea that we could pump directly from those aquifers isn’t likely,” he said.

When it comes to surface-water options, Blomstrom said options are limited for Rochester. The Zumbro and Mississippi rivers are being studied, and he noted it’s not uncommon for larger cities to start accessing surface water amid growth and increased demand.

He pointed out Minneapolis, St. Paul, Duluth and St. Cloud moved from solely tapping ground water to accessing surface water, with Minneapolis making the move a century ago.

Still, he said he remains hopeful that new aquifer options will emerge as study compares potential costs to benefits.

With more data expected in October, RPU General Manager Tim McCollough said next steps will start to be outlined at that time.

Regardless of the outcome, Blomstrom said they will take time, since large changes to water production efforts often take years.

“We have to make sure we are doing it in a responsible way,” he said.