Austin’s Historic Landmark Commission has approved using milled steel rods as replacement parts on 12 of the city’s iconic moontowers.

The commission OK'd the proposal from Austin Energy on Monday night. The electric utility is overseeing the restoration efforts, which began in 2014 and were initially expected to finish last year.

So far, five of the city's 17 remaining towers have been restored. The work stalled last year after contractors ran out of original replacement parts salvaged from two towers that had been taken down due to nearby construction.

Cara Bertron, deputy historic preservation officer with the city's Historic Preservation Office, said the steel parts will replace some of the worn-down, cast iron connectors and wrought iron rods on the 125-year-old structures. She told the commission nine towers will be restored, while the other three need to be completely reassembled.

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“Each of the 12 towers will have approximately 40% of original material remaining,” she said. “That accounts for the 40% failure rate on the towers that have been rehabilitated so far.”

Commissioner Kevin Cook said he has concerns about how well the new parts will match the original structures.

“But these being painted metal structures and with the elements in Texas, I think the moonlight towers will ultimately be about the DNA of the design more so than the original material,” he said. “It’s just impossible to keep something exposed like this. Keeping them alive is most important.”

City staff are also working on a strategy to inform how the original and replacement parts are interspersed in the towers. The proposal still needs approval from the Texas Historical Commission because the towers are designated state historic landmarks and on the National Register of Historic Places.

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