MISSOULA, Mont. -

A new twist on a story we've been tracking on Mountain Water Company.

First some history, Mountain Water operates Missoula’s only water system and is owned by The Carlyle Group, which is an international private equity firm.

The owners have refused to sell it to Missoula.

In response, the city is suing Carlyle and claiming that public ownership will quote "ensure the citizens of Missoula have long-term access to a stable, safe, plentiful and predictable source of clean water.”

Now, Missoula is teaming up with other cities who want control of their water sources too. Missoula met with Apple Valley, California to discuss their similar water situations.

The parent company Park Water Company owns both cities' water. Park Water Company is owned by The Carlyle Group.

Both Missoula and Apple Valley, California believe owning their water sources is best for them for many reasons.

Missoula Mayor John Engen just upped the anti.  It’s joining forces with Apple Valley.  Both city leaders believe this collaboration will bring them a bigger voice. 

"We can present a united front," said John Engen.

In Missoula Monday, Apple Valley representatives said their water rates are getting too high, too fast.

"Our situation here in California is getting more difficult all the time under a supplier of water that's coming under a private utility because our constant rate increases. The rate hikes are out of control," explained Frank Robinson, Town Manager from Apple Valley.

It's the same complaint in Missoula.  Both cities say full control is the answer.

"I think that we continue to be open to a conversation with Carlyle. If they'd like to figure out a way to do a deal with the city of Missoula and a deal with Apply Valley," said Engen.

After hearing about this collaboration, we reached out to The Carlyle Group. They didn't know anything about this. They sent us this statement.

"The Mayor's attempt to take this fine company by legal force is unfortunate and we will continue to vigorously assert our property rights."

And it doesn't stop there. Mayor Engen is reaching out to the other three water systems owned by park water company in hopes that they will join too.

"The essential resource that is water will be available to them at a reasonable price for a very long time and a way to guarantee that is through municipal ownership," explained Engen.

Despite the pressure from individual cities, Carlyle is showing no signs of backing down.  It plans to keep ownership of the water companies.