Urban honey bees are arriving in Seattle on Wednesday.

Around 20,000 Carniolan honey bees are arriving at The Sanctuary Seattle downtown, the city's oldest church. The church was recently revived by Daniels Real Estate, and a new event space and banquet hall were added.

The bees will live on the roof in specially designed hives where the honey will be harvested by chef Gavin Stephenson, the executive chef at The Sanctuary Seattle.

Chef Stephenson plans to use the honey in cocktails and recipes, but the project is also about sustainability and preservation.

WATCH: High tech honey bee hive to be installed at Seattle sanctuary

"There's not enough bees for the pollination we need," chef Stephenson explained. "If you think about it, every 1/3 bite you put in your mouth, a bee had something to do with it. So, if the bees go away, we go away."

The Sanctuary is starting with just one hive on the roof for now, with the goal of reaching up to 20.

Each colorful hive is designed by ZGF Architects where designers also installed lanterns that glow so people can watch the bees in the surrounding buildings. That includes tenants in The Mark, which is the city's newest skyscraper connected to The Sanctuary. The Mark is now Seattle's second tallest building.

"We have four different hives," said Ashley Dimick, Designer at ZGF Architects. "With our design, we wanted to sort of mimic what's happening in the hive."

Chef Stephenson, who is acting as bee-keeper, also oversees an urban hive on the roof of the Olympic Hotel in Seattle. He says there is no need to immediately plant flowers or a garden on the rooftop because the bees forage and pollinate up to six miles away.

"They are amazing creatures," said chef Stephenson. "We're lucky to have them."