He was planning to go back after work and see what needed to be done to fix them up.
Campaign spokesman Andrew Hollis said he did not believe anything "malicious" had happened.
"It's probably just kids.
"I don't think Phil Twyford came over one night and knocked them over in a fit of rage," he joked.
The campaign has since held a series of public protests, including a hikoi that blocked the highway at the Wairoa Bridge, in an attempt to influence the NZ Transport Agency and Government into speeding up decisions on the future of a series of projects related to State Highway 2 that were being re-evaluated, including the Tauranga Northern Link.
At the end of September, the agency said it expected to complete the re-evaluations in less than four months.