Street sweepers in two cities soon could be pulling double duty as spies.

Chicago is considering a three-year, $7.2 million contract to install and maintain 100 camera systems on its street sweepers—likely the first such application in the world. The agreement would allow Affiliated Computer Services Inc. (ACS), one of the nation's largest parking enforcement services, to perform image verification to identify potential violations. Final determination would rest with the city, which would issue the tickets.

The Washington, D.C., Department of Public Works also recently announced a similar plan. The department sweeps streets weekly during two-hour windows in the morning and afternoon, after which employees patrol the routes and issue $30 tickets to vehicles parked in sweeping zones. There are about 90 violations on every route.

“Every vehicle that's parked on the streets means that about three spaces on these streets are missed,” says Linda Grant, the department's public information officer. For every 10 miles that a sweeper misses, 100 pounds of oil and grease, 30 pounds of nitrogen, and 30 pounds of phosphorous—which promote algal growth in nearby rivers and remove oxygen from the water—are left on city streets.

“The technology supplements what parking enforcement does, since it can be extremely difficult to enforce all the street sweeping routes during the brief windows of time a city has to clean streets,” adds Barbara Roberts, vice president of the ACS public safety solutions group.

Washington, D.C.'s program is an outgrowth of a project launched in 2006 using license plate recognition (LPR) technology in the city's vehicle immobilization program so vehicles with three or more tickets within a year are booted. “It took boot crews a long time to input plate numbers, so it wasn't very efficient,” Grant says. “Washington is a compact city with a lot of cars and pedestrians; on any given day we have more than 40,000 visitors.”

The city council approved an act in May that would allow the cameras to be installed on 20 Elgin sweepers and to allow the department to mail parking tickets to violators.

Cameras will be used only on residential routes. “It's not about the residents themselves,” Grant says. “Often, people who don't live on that block park during street sweeping hours.”

Grant says the cameras cost about $36,000 each; installation, back-office support staff who monitor the images, and maintenance are calculated at about 10% to 15% of the purchase price. Grant estimates that with 30% compliance in the first month of the program, the city should receive about $747,000 in revenue; with 50% compliance in the first month, revenue is estimated to be about $534,000.

Although the potential revenues are impressive, the program is designed to influence driver behavior. The application has potential for use in other areas of city and county government as well.