DCC - Joining forces for a close look at South Dunedin ground

This media release was written by Dunedin City Council. The original is available to view on their website.

Dunedin (Tuesday, 22 January 2019) – The ground in South Dunedin will come under close scientific scrutiny in a new research project on soil conditions and below-surface water levels.

EQC, GNS Science, QuakeCORE, the Dunedin City Council, the University of Otago and the Otago Regional Council have joined forces on a project to test the soil and install instruments that can take water level measurements every 10 minutes.

EQC Senior Advisor John Scott says results from the study will help understand the effects of rainfall and tidal movement on the water level under the ground, and how the soil may behave in an earthquake.

“With solid scientific data from this project, the community can make better decisions on how to reduce risk,” he says.  “For example, we will have a much better idea of how wide and deep building foundations should be to handle conditions in an earthquake.”

ORC Engineering, Hazards, and Science Director Dr Gavin Palmer says the soil will be tested by cones pushed about 15 metres deep into the soil at about 20 different locations, mostly on road reserve, and water level monitors will be installed in tubes, called piezometers, at some of these locations.

“As well as giving us a better understanding of what’s going on now, the testing will help develop better computer models of the impacts of future storms and sea level rise,” Dr Palmer says.  “This in turn lets us better understand options to mitigate against and adapt to these effects in future.”

DCC Group Manager 3 Waters Tom Dyer says the DCC has budgeted $35 million on flood alleviation in South Dunedin over the next 10 years.

“The piezometer data will help inform options for exactly what that money should be spent on.

“The information will also be useful in preparing for an imminent flood, as response agencies will have a better idea of how much capacity the ground has to hold rainwater at any given time,” Mr Dyer says.

Installation is expected to start in the week of 28 January and data gathered from this project will be available on request from the Otago Regional Council.

More information/comment

John Scott, EQC Senior Advisor, 04 901 6611

Dr Gavin Palmer, ORC Director, Science, Hazards and Engineering, 03 474 0827

Tom Dyer, DCC Group Manager 3 Waters, 03 474 3873