Seventeen linemen at Dunedin City Council-owned Delta Utility Services will stage a 24-hour strike on Tuesday following failed mediation talks yesterday.
Delta and the 17 staff, who will picket the company's offices on Tuesday, are at odds over conditions being renegotiated in their collective agreement.
Engineering, Printing and Manufacturing Union organiser Mike Kirwood yesterday said mediation was undertaken as earlier negotiations over the new collective had stalled, but there was "no resolution" from yesterday's talks.
He said Tuesday's strike was "stage one of the campaign" and the linemen would discuss the possibility of further industrial action later next week.
Mr Kirwood did not believe there would be any disruption to consumers, except that non-urgent jobs could possibly take longer.