Tom and Pat Passaro of Waterford have been going to When Pigs Fly on Rope Ferry Road since the breakfast spot opened seven years ago.

"Actually, they usually have our drinks waiting on the table when we get here," Pat said at the diner on a Tuesday in late April.

Even during this late morning meal time on a weekday, most of the restaurant's tables were taken.

Regulars like the Passaros make up at least half the business at the restaurant, according to co-owner Sarina Costa, who also owns Mystic's Somewhere in Time Café.

When customers at the Mystic restaurant used to ask Costa when she was going to expand, Costa and her business partner, Gwen McGugan, used to joke, "When pigs fly." But in 2007 when they found the Waterford space and decided to open a second restaurant, the name seemed appropriate.

"It's been busier every year since we've opened," Costa said during a lull in traffic at the diner.

She described her regulars: There's Greg, who has his own personal bottle of Tabasco sauce kept in the restaurant kitchen; a Baptist pastor who comes in just about every morning for hazelnut coffee, a bagel and bacon; the "iced tea girls" who, as the name suggests, sip iced tea with every meal.

Olympic gold medalist Kara Wolters sometimes stops in with her family, Costa added.

"People like the atmosphere, because it's like being at home - you know, like being with your family," waitress Lauri Hary chimed in.

The restaurant is the latest of a long line of businesses to occupy the space since at least the mid-20th century, according to Municipal Historian Robert Nye. It follows two other popular diners.

Nye said that the original building that houses When Pigs Fly was built in the mid-1800s, and that the gable where the restaurant stands was added in the late 19th century.

The space occupied by the diner originally served as a residence, then later as a grocery store, he said. He said that since the 1940s, the space has held the Handy Shop, which sold various sundries including chocolate soda; the "legendary" diner Harriot's Kitchen; and in the 1980s and 1990s, the Village Stop diner.

Some customers - like Carol Johnston who grew up in Waterford - have been coming since the Stop occupied the space. Johnston now goes to When Pigs Fly every Tuesday to meet friends for muffins and coffee.

"It's close, close by," she said during one of those Tuesday meet-ups. "Food is good."

The popularity of the joint means parking can be hard to finagle. One of Johnston's friends did not make it that Tuesday because she could not find a place to park.

Recent renovations to the restaurant are intended to provide more space for those who have found parking to wait to be seated. Costa said the 30 percent expansion of space completed three months ago has been especially helpful during weekend shifts, when the restaurant sees 300 customers or more.

What won't be expanding are the hours of operation. When Pigs Fly is a breakfast and lunch restaurant that closes at 2 p.m., and Costa said it will stay that way for two reasons: to give her employees time with their families and to maintain quality.

"I don't wanna burn out," she said. "I wanna do this well."

T.TOWNSEND@THEDAY.COM