The Rail and Maritime Transport Union is setting up pickets at seven locations around Christchurch as its strike action continues.
The union's 200 port workers have said they will go on strike for 13 days, starting today, after negotiations with the Lyttelton Port broke down.
Union organiser, John Kerr, said union members will set up pickets at several port sites, as well as two haulage companies, and rail sites.
He said the pickets won't stop people from crossing, but to get the union's message out to the wider public.
Mr Kerr said the two key sticking points are the port company's refusal to pay staff who returned to work after an earlier strike notice was lifted, and refusal to give parity with another port union, the Maritime Union of New Zealand (MUNZ).
"[The strike action has] already had an impact as the company told us yesterday that they had cancelled all shipping through until next week. This isn't about making management suffer. This is about our members pride and dignity and trying to get a fair deal."
The Lyttleton Port has said it is disappointed that the union has refused a generous salary increase.
It said it was no longer asking the union to make roster changes, which were agreed to by MUNZ a year ago.
In a statement the Lyttelton Port said the MUNZ members received a salary increase of 4 percent this year and 3 percent for the next two years, because they embraced the flexible roster system.
John Kerr said the union was prepared to meet any time with the port to continue negotiations.
No update has been available from the Lyttelton Port this morning.