The Christchurch City Council says demand for portable toilets in the city has outstripped supply, forcing it to source portaloos from overseas.
The National Civil Defence Controller, John Hamilton, says more than 1000 of the portable toilets have already been distributed, but supplies are stretched, so hundreds more have been ordered from the United States.
Mr Hamilton says thousands of chemical toilets are also being delivered, and another 20,000 of those have been ordered.
The council is encouraging residents to use their red council bins for toilet waste and says storage tanks will be made available so people can empty their chemical toilets.
Mr Hamilton says a truck with 18 showers will also be visiting the most affected suburbs from Monday.
Heavy traffic holding up clearance
Heavy traffic is making the movement of waste around Christchurch difficult.
The city's three transfer stations are all nearly full but blocked roads are preventing trucks from moving that waste to the Kate Valley landfill, so the stations may have to close.
Chemical and portable toilets have also been affected, with the delivery of new units and the cleaning and emptying of existing units held up by traffic.
Civil Defence is asking those who do not have urgent business to stay off the roads.