Blaine has the right to separate its water system from Lexington, a judge ruled Tuesday, following a decades-long dispute over the smaller city's contaminated well water.

It's a crucial decision in a bitter saga about access to and control over the water supply for thousands of north metro residents.

Blaine has tried for decades to split from the water system it shares with Lexington, as officials argue their much-smaller neighbor's water has unacceptable levels of alkaline, calcium and manganese. Blaine has even accused Lexington of pumping contaminated water into the city without its consent.

Lexington has fought the divorce, arguing Blaine has been "bullying" its way into taking over the system the cities built together. The city has accused Blaine of aggressive tactics, including covertly sending crews across city lines to try to cut off water connections.

Unable to reach an agreement, Blaine in 2022 sued Lexington to separate from the system, and the case went to trial in January.

Judge Jenny Walker Jasper's ruling, filed on Tuesday, confirms that Blaine has the right to break off its water system and also states that Blaine owns a key water main in Lexington, having paid to build it.

"There exists no valid justification for forcing Blaine to continue to accept Lexington's untreated water to the detriment of its own citizens," the judgment says. "Nor can Blaine be compelled to sell or give its water to Lexington."

Blaine spokesman Ben Hayle said in a prepared statement: "We thank the court for agreeing that the City of Blaine has the right to have safeguards in place where our water system interconnects with our neighboring cities."

He said the city "is ready to move forward and work with Lexington under the parameters put forth in today's judgement."

Lexington City Administrator Bill Petracek said city officials will consult with the city attorney and discuss the judge's decision.

Much of the joint water system, Lexington Mayor Mike Murphy previously said, "was built on a handshake, with the mindset that this shared infrastructure would benefit the residents of both Lexington and Blaine.

"We need to return to that mindset — one that prioritizes collaboration over conflict and ensures that we act in the best interests of our constituents."

Tiny city left with costly choices

The judge acknowledged the two cities are in drastically different positions.

Since the cities agreed to a joint water system decades ago, Blaine has ballooned from a rural community to one of the largest north metro suburbs at 73,000 residents. Lexington has roughly stayed the same size with fewer than 3,000 residents.

The ruling opens up questions about how Lexington will move forward, as the city is left with costly options for cleaning its water or purchasing its supply from Blaine.

Blaine does not plan to completely abandon Lexington. According to the order, Blaine has stated its intention to close 12 of the connection points between the two cities' water systems. But Blaine would provide one-way valves on three of the connections, allowing Blaine's water to flow into Lexington to assist with firefighting needs, keeping the quantity available for that work about the same.

Lexington has done several studies to determine how to clean its water, but none of the answers are cheap.

City officials estimated that if Lexington purchases all of its water from Blaine, it would cost about $1 million. Constructing a system to blend Lexington's water with Blaine's to dilute and treat it would cost up to $3 million.

City officials estimated it would cost Lexington about $10 million to construct its own water filtration plant.

Decades of disagreement

Blaine and Lexington in the 1970s agreed to build out a connected system and provide water to both municipalities. But Blaine has long had concerns about Lexington's water quality, as well as many connection points never being metered, meaning officials can't measure how much of each city's water is flowing.

Blaine officials say the city has spent millions improving its water quality and building water treatment facilities.

Lexington continues to use a single well. Court records show the Minnesota Department of Health previously required Lexington to post notices about its water not meeting drinking water standards.

Blaine residents have complained when Lexington's well water has flowed into the city.

The cities have operated on an understanding that Blaine provides water to Lexington during the fall and winter, when demand is at its lowest. Lexington starts pumping water from its well during the high-demand, warmer months.

Blaine officials said the split would allow the city to provide fully filtered water to its residents. Lexington argued the separation would mean it loses critical access to water resources, plus it would "impose significant financial burdens on the city."

In the ruling, the judge wrote that the best solution for Lexington is likely to construct a system to blend the city's water with Blaine's to dilute and treat the well water, or Lexington could close its well and purchase all of its water from Blaine.