City Safe, Summer Safe and CCTV systems were also keeping close watch, resulting in the tagging not happening at all, or being removed early when it did occur.
He said taggers wanted fame and recognition but removing it quickly removed the value and purpose of the tag.
"We are finding that the most effective way to deal with tagging is to remove it quickly."
The lower incidents were also reflecting a change in society.
"Tagging is an indicator crime. Growing up is hard and young people can make bad decisions. Tagging is a bad decision - our young people are making better decisions," he said.
"Across the board, there is a committed effort to having a safer community."
Whangarei District Council spent $458,807 removing graffiti in the past three financial years to the end of June, 2016.
Over the same period the Far North District Council contractors spent about $42,329 removing 611 tags over three years, while in Kaipara 290 tagging incidents cost about $15,000.
Northland Regional Council's vandalism bill was small, as it only had to act when one of its four offices was targeted.