Butler County's population continues to rise, and its southwest corner continues to be the major driver of the growth.

The county added about 900 people in 2017, according to the U.S. Census Bureau's most recent estimates.

The biggest additions were 322 people to Adams Township, 287 to Cranberry Township, 266 to Valencia and 199 to Jackson Township.

Of the growing municipalities, Cranberry Township has showed the biggest growth since the 2010 census. The township has grown from 28,098 people in 2010 to 30,762, according to the bureau's 2017 estimate.

“Our population has been increasing for about 15 years,” said Jerry Andree, Cranberry Township manager. “We anticipated this population growth.”

Andree said the growth has brought to the town ship new businesses that are creating good jobs. He said Cranberry's government has been fostering an atmosphere that allows the municipality to grow without too much interference.

“We think (the growth) is a result of good planning that results in a great place to live and work and play,” he said. “We find companies locate to communities where their employees like to live. If you create a great place to live, companies will follow there.”

Andree said if Cranberry continues to build usable amenities like libraries and parks, then people will find it on their own.

“Our comprehensive plans map out everything we're doing until the year 2030,” he said. “We estimate our population (will be) 50,000.”

Other areas of Butler County, including Butler and Butler Township, are losing population, continuing a trend from recent years.

The city has 63 fewer people, while Butler Township has 69 fewer people, according to the 2017 estimates.

Butler Township has fluctuated at times, but the city has consistently decreased in population since the 2010 census. The city has decreased by 650 people and last year had a population of 13,107, according to the 2017 estimate.

“I'm kind of surprised by those numbers,” Butler Mayor Ben Smith said.

Smith said he has seen a good trend in young people moving to the city. He said Butler has been working to meet standards for what people are considering a modernized city.

“A lot of people are moving into cities that have easy walkability and upscale apartments,” he said. “While we are a walkable city, there's not always places to live that are conducive to that (lifestyle).”

City Councilman Jeff Smith said the population decrease is, in his opinion, a function of lower rates of homeownership. Smith said the city's concentration of social services makes it an ideal place for those who need them regularly to stay for a time, but leave when they no longer need the services.

“Unfortunately Butler has a pretty high transient population,” Jeff Smith said.

Smith said one positive is a more recent trend of young home-buyers who are choosing to settle down in Butler. Smith said the city's aging housing stock actually draws in some people, because of cheaper prices.

“More and more, you are seeing young people buying homes and fixing them up because buying a home is much less expensive than renting,” Jeff Smith said.

Ben Smith said residents are doing what they can to help the city stop the population slide.

He said projects like the Historic Architectural District, a grass-roots, residents-led movement to rezone the area near the Ritts Park District and preserve a neighborly community, are the types of projects that not only draw people to the city but entice them to stay.

Ben Smith said the combined efforts of the city and its residents could turn the trend around.

“We're trying to make the city safer and nicer,” Ben Smith said.