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This could be a matter of coincidence–the city may need extra Water Department workers every other odd-yeared winter. Or it could be that it’s handy to have a few more people on the payroll when incumbents are trying to get reelected. The trend was particularly notable in two traditionally clout-driven departments, Aviation and Streets and Sanitation. Together the departments boosted their staffing by more than 400 employees between the end of 2005 and this winter. Now they’re just about down to their previous levels.

There is one other possibility: the city might not keep accurate records. According to the data I’ve been supplied, the Mayor’s Office of Special Events went from 63 employees in December 2005 to 340 this week. “That’s not correct,” said department spokeswoman Cindy Gatziolis. Actually, it might be: Gatziolis said the payroll included many seasonal workers hired to provide security for summer events or help with the city’s Jumping Jack program–which brings neighborhood festivals and parties those giant, inflatable playpens for kids to bounce around in. Gatziolis said the department had 233 employees listed in January–when demand for the Jumping Jacks isn’t quite as high–because it just left people on from last summer so it wouldn’t have to jump through as many hoops when it came time to hire people for this summer. “They were kept on the payroll but not paid,” she said. “They were dormant employees.”