Each report of potholes, overgrown lawns, busted stoplights and other issues to Minneapolis 311 cost city taxpayers $9.15 last year, a per-contact expense that surpasses most cities across the country.

When it launched 311 six years ago, the city joined a national trend of creating nonemergency avenues for citizens to interact with City Hall. The popular service handled 335,427 calls and e-mails in 2011, but fewer inquiries and high labor rates have driven up the cost to handle each contact.

That cost per contact -- a key measure of the service's efficiency -- has risen by $3.67 since 2007. It grew $1.28 between 2010 and 2011 alone because 65,000 fewer calls and e-mails poured in and the costs of running the center remained constant.

Minneapolis 311 director Don Stickney said fewer people called in 2011 because of shorter operating hours -- the result of budget cuts -- and a warm winter that limited the number of snow-related inquiries.

City officials acknowledged in a January presentation that Minneapolis' 311 costs per contact in 2010 exceeded every city in a comparative survey of 39 311 organizations. "A key driver of the cost per contact is personnel-related expenses," said a city performance measurement report, which added that it's hard to compare cities since Minneapolis lumps IT and overhead expenses into its calculation.

Stickney attributed the generally higher per-contact expenses to high labor costs, longer call times and the city's unique accounting practices.

"We are an outlier from that perspective," Stickney said of how Minneapolis' per-contact costs ranked with other cities in the comparative survey.

Spencer Stern, a Chicago-based consultant who specializes in 311 systems, said the Minneapolis 311 service is a national leader because of its technology, extensive data sharing and early track record demonstrating its value after the 2007 Interstate 35W bridge collapse.

"It's one of the best-run call centers in the entire United States," Stern said.

At the Lyndale Neighborhood Association, residents take annual "311 walks" of the neighborhood to report problems. The association's executive director, Mark Hinds, said it's especially helpful for residents to develop an electronic trail of reports about specific problem properties.

"I think it's a very valuable city service," Hinds said. "It really helps streamline a lot of things."

The city pays about $3 million to operate 311, a figure that has fallen by about $200,000 over the past three years. About 67 percent of that cost is attributable to salaries and benefits -- there are currently 28 employees.

Under union agreements, workers in the Minneapolis 311 call center workers make a starting salary of about $17.13 or $19.52 an hour, depending on their prior experience.

Only eight of the 39 cities from the comparative survey reported a higher starting salary than Minneapolis in 2010, and four of them were in Canada.

"Like so many other areas of city operations, they really need to take a closer look at how they compensate their employees," said Jonathan Blake, vice president of the Freedom Foundation of Minnesota think tank, which advocates limited government. Blake's organization recently researched the 311 cost per contact.

Minneapolis Mayor R.T. Rybak said it is difficult to make city-to-city 311 comparisons, but he credited the city's performance measurement system with bringing the statistics into focus.

"The bigger issue is what would it cost us if we didn't have 311," Rybak said. "We know the costs would be dramatically higher by having isolated call centers and really inefficient ways of getting service delivered."

Rybak added that the "ultimate" way to improve 311 efficiency would be to operate it 24 hours a day and add more users, such as counties, other cities or a university. But budget constraints have forced the city in the other direction -- in April 2010, hours were shortened by four hours, running from 7 a.m. to 7 p.m.

The city has tried to offer more 24/7 capabilities. Last Wednesday, it unveiled a mobile application that will allow residents to file reports whenever they spot a problem. Online reports are not factored into the city's per-contact expense calculation, however.

City-to-city 311 cost comparisons can be tricky, since each city generally calculates expenses differently. Each department in Minneapolis, for example, must account for its internal IT expenses. That and other costs, such as phones and insurance, make up about 31 percent of the city's total 311 expenses. Stickney said other cities may not be factoring those into their 311 budget calculations.

The city's goal is to bring the per-contact cost down to $8.55 for 2012. "We're expecting that we will have a more normal winter, quite honestly," Stickney said.

Eric Roper • 612-673-1732 Twitter: @StribRoper