Local Government Magazine
LG Magazine

Smart solutions – Earthquakes

Christchurch 2011: Flooding of streets caused by liquefaction. Photo courtesy of Tonkin + Taylor.

How could local authorities improve how they prepare for, and respond to, the possibility of earthquakes in their regions? Patricia Moore investigates.

Graphic images from September’s earthquake and tsunami in Indonesia are yet another reminder of the fragility of the earth’s crust. Closer to home, the Kaikoura and Christchurch earthquakes were an indication of how under-prepared we are for a significant seismic event. But with service offerings changing, smarter solutions are readily available for local bodies.

Dave Dekker, technical principal, earthquake engineering and building structures at WSP Opus, says since the Kaikoura quakes his firm has cemented in changes.

“Our damage prediction tool has been further refined to allow targeted rapid assessment of key client infrastructure, ensuring prioritised access for maintenance and repair.

“We’ve also developed smart technology where real-time instrumented monitoring of a building can be remotely accessed to review the actual effects of an earthquake and inform decisions on likely damage and required repair.”

Dave says WSP Opus has also trained additional staff in inspecting damaged buildings, emphasising both technical and health and safety aspects, and developed a model whereby, following the rapid building assessment process, a senior engineer is sent in to explain to client leadership teams what impact, if any, the event has had.

“For local authorities, advancement of damage prediction tools means that rapid assessment efforts can be prioritised and targeted where they are most efficient in the critical first hours after an event.”

It’s a similar story at Stantec. Civil water team leader, Stephanie Thompson, says changes have taken place in the firm’s emergency planning and management area. This is particularly the case when looking at the resilience of networks immediately after earthquakes or natural disasters, and up-skilling capability to carry out robust condition assessments for council infrastructure.

“For local authorities, this means more collaborative team environments to carry out urgent repair projects quickly and efficiently,” says Stephanie.

Where, historically, councils have focussed their planning primarily on emergency response measures, Tonkin + Taylor technical director Mike Jacka says he’s seeing a greater understanding of how complex and challenging the longer-term recovery can be.

Mike’s based in Christchurch where, he says, everyone now thinks they understand the liquefaction hazard – because they either had liquefaction on their land or they didn’t.

“The problem is that the next earthquake might be quite different to previous ones,” he says. “Christchurch City Council has recognised this and is taking a wide range of future earthquake scenarios into account when determining liquefaction assessment requirements for resource and building consents.

“We’re currently working with the council to develop an interactive ‘liquefaction laboratory’ public awareness website which aims to help people better understand the range of liquefaction damage that may occur in future.”                 

Dave agrees awareness of risks has increased. He notes that many local authorities are now more connected across the emergency management sector. And, he says, available resources, particularly online, are raising awareness of emergency preparedness and planning.

He suggests local authorities without inhouse specialist engineering resources should pool resources with neighbouring authorities or consider specialist advice when planning their response plans.

“We’re assisting many local bodies to assess their risk exposure to earthquakes in a number of ways including seismic assessment of council-owned buildings and critical infrastructure, as well as providing engineering advisor services and contracting to councils to provide staff resource in an emergency.”

Dave Dekker; Technical principal; earthquake engineering and  building structures, WSP Opus.Stephanie Thompson;  Civil water team leader, Stantec. Mike Jacka; Technical director, Tonkin + Taylor.

He says WSP Opus was on the ground immediately following the Kaikoura earthquake and had several senior staff members working exclusively for Wellington City Council helping manage building assessment information to understand the impacts on the city’s building stock.

Stantec’s principal engineer and Nelson team leader Don Young has been supporting Kaikoura District Council in its rebuild and recovery programme since 2016.

Stephanie explains she was appointed as acting infrastructure recovery manager, which encompassed substantial tasks in initially identifying asset damage and quick responses to get the systems back up and running.

“Don then led the negotiations and achieved a successful outcome with the funding agencies on behalf of the council. In addition, we’re part of the Kaikoura District Council panel, assisting with the rebuild programme including three waters, community facilities, structures and roading, helping to streamline tendering processes and to produce smart and resilient designs.”

She suggests councils could be more pro-active on several fronts. She lists improved collection of underground infrastructure data; collecting information electronically, not on paper; and improving the efficiency of current business-as-usual processes.

Stephanie also suggests council move from paper forms and maps to electronic data; install resilient infrastructure, such as flexible pipelines; and improve CCTV assessment processes in preparation for an earthquake.

“This data can be used as a baseline to determine the repairs required as a direct result of the earthquake.”

Stantec worked with Wellington Water to complete a resilience study identifying critical areas within its network and determine a skeleton network with water supply distribution points that could provide a basic level of supply during an emergency event, says Stephanie.

“We developed innovative sets of algorithms that identified approximately 400 kilometres of critical networks with approximately 240 kilometres requiring seismic resilience upgrades. We then developed a three-stage critical network upgrade programme with capital expenditure spread evenly across each stage.”

Natural disasters, such as earthquakes and cyclones, have an unfortunate tendency to highlight pre-existing risks nobody had given much thought to beforehand, says Mike.

“A question we often ask when issues like liquefaction, rock-fall, and flooding occur, is, ‘how would you have managed this hazard if it came to light before the event?’.

“All too often there’s no clear answer. I think local authorities would do well to make sure they have a practical and consistent approach to natural hazards management now, so they don’t have to work it out from scratch and under intense pressure, after a disaster strikes.”

When it comes to planning how to respond, and then recover, from a disaster, Mike favours the ‘plans are worthless but planning is everything’ school of thought.

“The very nature of a disaster is that it’s unexpected. So, inevitably, it won’t eventuate as you were planning. But if people are empowered with the skills, information and support to make good decisions when the time comes, things have a way of working out for the best.”

• Patricia Moore is a freelance writer. mch@xtra.co.nz

This article was first published in the November 2018 issue of NZ Local Government Magazine.

Subscribe to Local Government Magazine >>

Related posts

Three Into One

LG Magazine

Flawed Thinking

LG Magazine

LED for Auckland

LG Magazine