Delaware County residents realize the county's cities and villages are growing rapidly -- and new data from the U.S. Census Bureau bear that out in Sunbury.

At the end of May, the bureau released its annual population estimates for communities across the country. Those estimates suggest Sunbury is well over the threshold for city status when the next official census takes place in 2020.

According to the data, Sunbury is estimated to have 5,216 residents, easily surpassing the 5,000 needed to become a city. By that figure, the village has grown by more than 18 percent since the 2010 census, when it registered 4,389 residents.

For Village Administrator Allen Rothermel, who has watched Sunbury become a hotbed for development, that figure is far from shocking.

"It doesn't really surprise me," he said. "In May, we had something like 35 building permits issued, and we had right around 36 total for the year before. So just by May, we're already there."

The extra demand for building permits and other logistical necessities already is affecting the village.

"As much as that doesn't sound like much of a jump, in terms of staff and our one zoning person ... it's literally tripling the amount of homes built in a year along with the community development on the heels of that," Rothermel said. "It's really going to make for a challenged workforce to be even more challenged."

As the transition to city status looms, Rothermel said, the estimates only "confirm what we already suspected."

"I don't think anyone here has thought for a second that we're not going to be eligible for city status (in 2020)," he said. "That's not even something we've entertained."

Although Sunbury will remain a village for more than two years, preparation already has begun for the transition into a city.

Rothermel said village leadership is planning for the process of establishing a charter and assembling an 18-person charter committee. He said it likely would take a full two years to have everything in place for the process.

Although the overwhelming growth is "a good problem to have," Rothermel acknowledged it's a lot of work.

"It's just going to be a different mindset in terms of pretty much every operation," he said. "What we want to get right is to have the right number of staff in place and everything so that when things really start to ramp up, we're ready."