While workers cause the population of Sauget to balloon 10 times its normal size, the village of Shiloh sees its population drop more than 40 percent each week , according to the U.S. Census Bureau.
The estimates are intended to help city leaders plan for emergencies and include cities with more than 2,500 workers -- more than 6,900 such cities nationwide.
For example, in the 2010 census, Sauget's population jumped from 243 residents to more than 2,600 people because of workers flooding into the village. The jump represents the fourth greatest increase in the percentage of a community's population in the state, and 19th in the entire country.
Sauget Police Chief Patrick Delaney said he was not surprised to hear of the population jump because the village is home to the Gateway Grizzlies baseball stadium, part of the St. Louis Downtown Airport, multiple chemical plants, barge companies along the Mississippi River, a 700-acre industrial park, and four night clubs.
The biggest concern for Sauget police is the influx of people at night to visit the village's four night clubs, Delaney said. The clubs stay open until 6 a.m. or 24 hours a day and require the department to double the number of officers on duty from two to four officers per night shift.
"What is unique about Sauget is when people learn our population is about 240 people they always ask, 'What do you have, one police officer?' No, we have 12 officers because we have 2,000 people who work in the town and especially for the weekends when we have 4,000 to 5,000 people coming to the night clubs in the area," Delaney said.
In terms of the number of workers, Scott Air Force Base sees the greatest increase in the metro-east. Nearly 11,000 workers enter the base each day, more than tripling its population to about 15,600 people.
The base also had the greatest percentage of workers who also live there with 77 percent. Highland followed with 48 percent, and Edwardsville with 37 percent.
Belleville remains the largest employment center in the metro-east with an estimated 21,600 people working in the city. Workers cause the city's population to jump 10 percent to about 48,400 each day.
On the other hand, O'Fallon sees its population decrease about 11 percent each day for a weekday population of about 24,100 people.
On the opposite end of the spectrum, Shiloh sees its population drop from about 12,000 people to 7,200 during the day. The estimated 4,800-person drop stems from commuters leaving the village for work elsewhere. The 40 percent drop in population is the sixth-greatest such change in the state, according to the Census Bureau.
While the population may drastically change, police staffing is determined through a statistical analysis of the department's calls for service, Shiloh Police Chief Jim Stover said. For example, Shiloh police receive more calls for help on Fridays and Saturdays.
"As far as looking at whether this is a bedroom community or not, it really doesn't determine staffing or when I have people on," Stover said. "Basically, it is when our statistics show we need officers."
Shiloh trails the metro-east with only 7 percent of its residents working in the village. Glen Carbon and Swansea follow close behind with about 10 percent of their residents working in those villages.
Statewide, Chicago sees the biggest jump in population due to commuters. The city's population jumps more than 177,000 people during the day to total about 2.88 million people.
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Contact reporter Daniel Kelley at email@example.com or 618-239-2501.