Land Information New Zealand (LINZ) has appointed Opus, Beca, and CPG to carry out critical re-surveying work in post-quake Canterbury.

The three firms will share the significant task of restoring the region's vertical control network – the system of about 400 geodetic survey markers that enable the accurate determination of heights.

The government recently gave LINZ an additional $850,000 towards this and other earthquake-related surveys in order to discover how the position of the land has changed – information that is critical as the region's infrastructure is re-established.

Land Information New Zealand’s (LINZ) Chief Geodesist, Graeme Blick, said the work was vital.

"We have already seen that large areas of Canterbury have experienced movements – both horizontally and vertically – in excess of 10cm, and close to the fault line there have been movements of more than a metre," he said.

"Precise levelling data is required in a very short timeframe, to ensure the region’s hazard monitoring abilities are not compromised. Given the flat landscape of Canterbury, this survey work is vitally important to local authorities and property owners."

The work is expected to be completed by June 2011.

LINZ will also be tendering for contracts to restore the horizontal control system – a separate network of survey markers used for mapping, which is especially significant when it comes to re-establishing property boundaries.