When Mayor Charlie Hales last invited the city's largest industrial water users to City Hall, the meeting did not go smoothly.

"The mayor has called us political terrorists," said Tom Keenan of the June meeting where multiple attendees say Hales yelled at large water ratepayers about plotting a "hostile takeover" to remove Portland's water and sewer bureaus from City Council control.

That coup has grown into a ballot initiative campaign calling for the creation of an independently elected public water district to set utility rates.

And Hales's calendar shows he's scheduled another meeting with Keenan—the president of soft-drink packer Portland Bottling Co., one of the chief political backers of the district. The mayor and Keenan are slated to meet Thursday.

Portland Bottling Co. has become the first and largest donor to the ballot initiative. The company gave $25,000 on Sept. 5 to Portlanders for Water Reform, the political coalition of activists and ratepayers created to put an initiative on the May 2014 ballot.

Hales says this week's meeting, which will also include City Commissioner Nick Fish, was Keenan's idea.

"Mr. Keenan asked for the meeting," Hales said this afternoon. "The agenda will be whatever he wants to talk about. I'd be shocked if we didn't talk about water."

This time, the meeting will be held at Keenan's Northeast Portland office. He could not immediately be reached for comment.