Model Maggie Rizer Is Engaged!

 Astrid Stawiarz/Getty Images

Maggie Rizer is engaged!

The former supermodel will say "I Do" to businessman Alex Mehran on  Sept. 18 in upstate New York, she told at the HauteLook party in New York City Thursday.

"We're getting married on Lake Placid in the big foliage season. I grew up right near there," Rizer, 32, tells Us.

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She wants her dress to be "very elegant, almost like Marni [or] Balenciaga feeling, but elegant, like couture. I want a very corset, fitted, gorgeous couture gown. Pop it in Lake Placid there!"

Mehran, 28, proposed on Rizer's birthday, Jan. 9. By the end of the day, she'd already "knocked out all the details" of their big day, she jokes.

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"He was not happy. He was like, 'Can't we just enjoy it for a second?'" Rizer laughs.

The couple met 10 years ago through his sister and mutual friends, including model Karen Elson. But they didn't turn romantic until they had "an amazing date in Paris," Rizer explains.

Rizer was "in Paris doing couture… and he was studying in Bologna, because he's a few years younger than me," she says. "He brought me to this amazing restaurant that only he remembers the name of because of course, I was busy working and was like, 'You make the reservations.’”

But after their Eiffel Tower date, they fell out of touch. "I was dating somebody, or he was studying abroad. Then finally, three-and-a-half years ago, we got together," she says.

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So what are the newly engaged plans for Valentine's Day?

"To make out," Rizer tells Us.

Rizer was last in the news for accusing her stepfather of embezzling millions of her modeling earnings — leaving her $2 million in debt to the IRS. He was sent to jail shortly after.

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