Last summer, New York mayor and soda-hating bazillionaire Michael Bloomberg’s charity launched “The Mayors Challenge” to award $9 million to five cities “that come up with bold ideas for solving major problems and improving city life.” The field has now been whittled down to 20 top concepts.

“From sustainability and public health, to education and economic development, cities are pioneering new policies and programs that are moving the country forward,” said Bloomberg in announcing the contest. “Historically, cities have seen each other as competitors in a zero-sum game, with neighbors pitted against each other in a battle to attract residents and businesses. But more and more, a new generation of mayors is recognizing the value of working together and the necessity of borrowing ideas from one another.”

Bloomberg seems to miss his own point, though, in setting up a battle for funds between cities, some of which have far more resources and innovation street cred than others (I’m looking at you, San Francisco). That’s part of why I want to give a special shout-out to Milwaukee’s entry for the city’s HOME GR/OWN project.

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From Milwaukee Mayor Tom Barrett, writing at The Huffington Post:

Imagine vacant lots becoming orchards, gardens, and small farms. Envision foreclosed houses repurposed as small-scale food processing centers and neighborhood nutrition education sites where people connect to prepare and share healthy food. Imagine neighborhoods where foreclosed properties become assets in a campaign to improve healthy food access and demand.

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This kind of a project could turn land use on its head for cities struggling with foreclosures and poverty. Municipal governments are often notorious landholders, keeping a grip on more empty properties than even the biggest, baddest developers and banks.

The other 19 Mayors Challenge finalists have some cool ideas too, from a one-bin recycling system in Houston to a “smart energy neighborhood model” in Phoenix.

But I gotta root for the underdog here. Milwaukee’s population has shrunk by about 5 percent over the last 20 years and the city has been plagued by foreclosure, but Mayor Barrett has long pushed for sustainability. Give ’em the cash, Bloomberg — they can put it to good use.