Mayor Frank Cownie and developer Jack Hatch traded barbs Thursday over the state of Des Moines’ water utility and the taxing of the city’s residents as their campaigns close in on the Nov. 5 election.

Speaking with the Des Moines Register’s editorial board, Hatch, a former state senator, challenged the mayor's assertion that he’s worked to ensure the long-term availability of affordable, clean water in the city.

“Frank, you have not done that,” Hatch said. “I sat on the water board, and I watched you from the state Senate, and there is no plan that has been developed to ensure the quality of our water continues.”

Over the past two years, Des Moines Water Works has workshopped how it would form a regional water utility that would give the suburbs more say in the distribution of the local water supply.

Last month, Hatch released a previously confidential memo, describing the regionalization push as a “Flint-like secretive takeover.”

More:Des Moines Water Works unveils plans for regional water utility

On Thursday, Cownie accused his opponent of “fear-mongering.”

“It destroys the trust that we have spent years to build so that we can establish that trust with our neighbors, with our customers and with the communities that water works serves,” Cownie said.

Hatch has called the regionalization talks a secret process and accused the city of abdicating its responsibility by not being involved.

Cownie and Hatch were joined by fellow mayoral candidates Joe Grandanette and Chase Holm for the Register's editorial board.

Hatch and Grandanette both agreed that the Des Moines residents should vote on whether Des Moines Water Works should partner with its suburban customers to form a central Iowa water utility.

Cownie, the longest-serving mayor in Des Moines’ history, and Hatch, a former Democratic gubernatorial candidate, also clashed over property taxes.

Hatch said he’d tried as a senator to freeze property taxes for seniors still living in their homes, something he also wants to do if elected mayor.

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Cownie said Hatch should instead focus on reducing income taxes because freezing property taxes would take money away from the city and other taxing authorities, like the school district.

The mayor pointed to earlier this year when the city cut the property tax levy by 60 cents, following the passage of the 1-cent local-option sales tax.

“You need to reduce their tax bill, and that includes a lot of things,” Cownie said.

“But that’s what you didn’t do,” Hatch replied.

He said Des Moines residents' property tax bills still increased despite the cut in the levy rate because property assessments increased.

Cownie said the city fulfilled its promise and cannot be held responsible for assessments, which are dictated by the county.

On taxation, Holm, an Army veteran who’s still in the reserves, said developing on land is almost like a punishment because of the resulting higher property taxes. He rewinded back to the 19th century to the idea of implementing a “land value tax,” in which land, and not the structures built on it, are taxed.

“What it does is it incentivizes people to develop their housing," he said. "It doesn’t help the people who are speculating that have little flat parking spaces. They sit on it so that when the city booms, they can make money off everybody’s labor.”

Grandanette, a former teacher and coach, said downtown tax abatements have taken too much revenue from the city for too many years and put the tax burden on homeowners.

“We’ve got to figure out a better way to do this so that all the citizens prosper,” he said.

Austin Cannon covers the city of Des Moines for the Register. Reach him at awcannon@registermedia.com or 515-284-8398. Your subscription makes work like this possible. Subscribe today at DesMoinesRegister.com/Deal.