UPDATE, AUG. 16, 12:18 P.M. CT: More than 90% of Unite Here Local 1 members voted in favor of a strike, the Chicago Sun Times reports. If a new contract is not signed by Aug. 31, workers at hotels including the Palmer House and Sheraton Grand Chicago will walk out.

ORIGINAL STORY: Come Sept. 1, roughly 30 Chicago hotels could be impacted by a strike that would leave properties more vacant and a lot dirtier.

Members of Unite Here Local 1, a union of more than 15,000 hospitality workers in and around Chicago, are voting today on a possible strike that would take effect that day if a new collective bargaining contract is not signed, the Chicago Sun Times reports. The previous contract expires in three weeks.

The strike — centered largely around properties cutting staff positions and overburdening those that remain, according to a video on Unite Here Local 1's website — impact more than two dozen Chicago hotels.

"Business is booming. Fifty-five million tourists came to Chicago last year. In 2017, Chicago hotels made over $2B. That's more than ever before. We know the companies can afford our demands," the video said.

Choose Chicago reports hotels in the city posted $2.3B in revenue last year, about $30M more than 2016. Chicago tourism has been steadily increasing for years, and surpassing the 55 million visitors mark is a win for Mayor Rahm Emanuel, who had set a goal to reach that point by 2020. Occupancy in Downtown hotels was more than 90% in June, according to Choose Chicago. Last year set records for demand, but average daily rent dropped slightly.