An earthquake was felt today in Samoa almost at the same hour the tsunami struck a year ago.

Incumbent Bob Parker is way ahead of rival Jim Anderton in the Christchurch city mayoralty race, according to a poll issued today.

Sewage will flow into the Kaiapoi River for at least another month and it could take a year to rebuild all the area's quake-damaged sewerage systems.

There has been more earthquake activity in Canterbury this morning and overnight with eight strong aftershocks continuing to rattle the region.

Liquefaction was a huge problem, and many hard-hit Bexley residents believe that was because their homes were built on what was once a swamp.

At least three aftershocks have hit Christchurch in quick succession this evening, the latest a magnitude 4 quake centred within 5km of Christchurch at a depth of 9km.

To protect the occupants from the elements, tarpaulins are strung up between the poles to create makeshift walls.

Things are looking up for thousands of householders in areas worst hit by the Canterbury earthquake.

The Government hopes it will be able to give thousands of Canterbury property owners in the worst earthquake-hit areas some idea of what the future holds by the middle of next week.