Graffiti removal by drone underway in Washington state

• Using drones can free up maintenance workers while helping paint over graffiti in places that are difficult or unsafe for workers to reach, the report says.

Catch up quick: State lawmakers authorized a pilot program last year to test how well drones armed with spray paint could cover up graffiti alongside freeways.

• As of last month, the state had spent about $22,000 testing the graffiti-fighting drones, and planned to spend another $38,000 by the middle of this year.

What they found: The report calls the drones "a very effective" tool, particularly when removing tags in "precarious locations" that could injure workers.

• The drones also can cover up graffiti more quickly than workers, deterring taggers from "retagging" the same area, per the report.

What's next: Transportation officials are recommending that the state buy more drones to expand the program.

• The state is also testing the use of radar and cameras to catch taggers in the act.