Child care operators say they are overwhelmed and unable to serve Calgary's quickly expanding population.

Statistics Canada figures released on Wednesday confirmed that Calgary was one of the fastest growing cities over the past five years.

And much of that growth can be attributed to a baby boom: hospitals in and around Calgary recorded nearly 18,000 births in 2011.

That boom is pushing an already stretched child care system to its limits, operators say.

Elna Bitu said demand for infant spaces at her downtown daycare is the highest she's ever seen.

Daycare operators say it's hard to keep up with demand for spaces in fast-growing Calgary. (CBC)

“We have a waiting list of at least 20 children," she said. "I've never been so busy.”

It’s a similar situation throughout the city. Callers to the University of Calgary's daycare centre hear this message: "We are currently handling an overwhelming number of phone calls at this time.”

The province is trying to meet the constantly growing demand by offering incentives to operators to hire more staff and open more infant spots, officials said.

"I know it’s difficult if you are a mother trying to get back into the workforce but again I really again encourage that parent to contact their local child and family services authority," said Cathy Ducharme, who speaks for Alberta Human Services.

Ducharme said Child and Family Services staff can help parents find the best care available for their children.