Many U.S. Cities See Huge Daily Population Swings

The Amazing Effect of the 'Bedroom' Suburbs

Traffic on busy freeway
Some Cities See Huge Daily Population Swings, Census Says. Getty Images

Does your city seem more crowded on weekdays than at night or on weekends? It very well may be, according to first-ever estimates of daytime populations just released by the U.S. Census Bureau.

The concept of the daytime population refers to the number of people, including workers, who are present in a city or town during normal business hours, in contrast to the resident population present during the evening and nighttime hours.

Perhaps more clearly than ever, these figures reveal the extent of the growth of suburban "bedroom" towns and the major reason Americans now spend over 100 hours a year commuting to and from work.

Among cities with 100,000 or more people, Washington, D.C.; Irvine, California; Salt Lake City, Utah; and Orlando, Florida, show the highest percentage increases in population during the day as opposed to their resident population.

"Information on the expansion or contraction experienced by different communities between nighttime and daytime is important for many planning purposes, including those dealing with transportation and disaster relief operations," said Census Bureau Director Louis Kincannon in a press release. "By providing information on the number of people not living in the area, but nevertheless greatly affected by the event, the data can provide a clearer picture of the effects of disasters such as hurricanes Katrina and Rita."

The places where the largest percent increases in daytime over nighttime populations occur tend to be those with small resident populations. For example, among medium-sized cities, Greenville, S.C., has a daytime population that is 97 percent higher than its nighttime population. Palo Alto, Calif., increases by about 81 percent, and Troy, Mich., by 79 percent. Among very small places, gains approached 300 percent in Tysons Corner, Va. (292 percent), and El Segundo, Calif. (288 percent).

Other highlights from the Daylight Population Estimates include:

  • New York City has the largest estimated daytime population, at more than 8.5 million persons. The increase of more than half a million people over the nighttime population is bigger than that found in any other area. However, the 7 percent increase puts New York in the middle of the pack on percentage change among cities with more than a million residents.
  • The second highest numeric daytime increase is in Washington, D.C., where 410,000 workers boost the capital’s population by 72 percent during normal business hours.
  • Other big cities with large daytime gains are Atlanta (62 percent), Tampa (48 percent), Pittsburgh, and Boston (both around 41 percent).
  • Typical examples of sizable expansion of daytime populations in small cities can be found in places such as Paramus, N.J.; Redmond, Wash.; and Beverly Hills, Calif., among others.
  • About 250,000 people worked in New Orleans prior to Hurricane Katrina. Almost 150,000 of these workers were residents of New Orleans, but the remaining 100,000 lived outside the city.
  • One of the most extreme examples of daytime population increase is Lake Buena Vista, Fla., which has almost no permanent residents but swells to an employment center of more than 30,000 people during the day.