Surprise's economic development team celebrated a special birthday this month with a celebration that looked like any other birthday party.

There were cone party hats, "happy birthday" signs, decorations and a Costco cake.

Except this Costco cake wasn't for one of their team members. It was for Costco. The whole party was for the retail giant.

The northwest Valley 'burb is getting increasingly creative.

For years now, Surprise residents have said they wanted a Costco. For years now, Costco has been mum about whether it plans to come.

Costco declined to comment on this story, for example.

So the city has pressed on. The birthday party is just one scheme on a list of fawning the city has done in the last few years to attract the popular store.

RELATED: Costco, Hobby Lobby, discussed for Surprise, city emails show

Costco is No. 1

The city first realized just how badly residents wanted a Costco in 2015 when it did its first survey asking residents to name top retailers they wanted in the city.

More than 3,000 residents responded, and half of them named Costco. Costco was No. 1 on the list.

"It was so overwhelming, it was the first time it generated a conversation," said Jeanine Jerkovic, the city's economic development director.

The city called the retailers on the top 10 list, which also included Hobby Lobby, Old Navy, and Texas Roadhouse, Jerkovic said.

But that wasn't enough. They needed more. So they got balloons. They got signs. Then, they all got together and took a photo where they are all smiling and laughing, and a few are jumping in the air.

That was just the start.

Celebrating Costco's birthday

The next year, the city was having an employee appreciation event. Each department decorated a totem pole.

Costco was at the top of the economic development's pole.

This is how the birthday tradition got started. The city took a photo of the totem pole and sent it to the retailer in a birthday card. "You're at the top of our retail totem pole!" the card said.

The city considers the retailer's birthday to be the anniversary of the day Costco opened its first store, on Sept. 15, 1983.

The next year, in 2017, the city sent the retailer a postcard. "Wish you were here," it read.

That year, the city did a second resident survey, and Costco topped the list again.

Emails reveal potential location

By sending Costco fun notes, Surprise hopes to stand out in a crowd and build a relationship with the company, Jerkovic said.

"Whatever business you're in," she said. "You're in the people business. Having them get a sense that we want to welcome them — that's so important."

Last year, The Arizona Republicobtained emails from the economic development team to Costco pitching a store for Prasada, a development straddling Loop 303 between Greenway Road and Peoria Avenue.

A flurry of speculation continues. Nearly every month, a resident posts on a community page on Facebook about Costco.

This year, economic development staff and other city employees decided to throw the party for Costco.

A party to which Costco would not come.

What say you, Costco?

The closest Costco location to Surprise is the Arrowhead area of Glendale. That's about 20 to 30 minutes away for many Surprise residents.

As Surprise grows and sprawls farther north and farther west, it may become more likely that Costco will come. But Costco representatives don't comment on things like this.

The Republic sent the company a list of questions, including whether it was coming and what it's birthday wish was, and a company representative replied and said the company would not comment.

Jerkovic said she has reached out to the company as recently as May. Asked whether she thinks Costco could come, she gave a comment sure to give rise to even more speculation.

"It's closer than it's ever been," she said.

Reach reporter Jen Fifield at jen.fifield@azcentral.com or 602-444-8763. Follow her on Twitter @JenAFifield.

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