December 3, 2012
ORC to activate improved flood alert system
The Otago Regional Council (ORC) is converting to a more efficient and effective system of alerting the public to
predicted or actual flooding in the Otago region.
ORC director of environmental engineering and natural hazards Gavin Palmer said the council was transitioning towards
using social networking device Twitter to send alerts to cellphones, and away from telephone ring lists.
Dr Palmer said this would allow anyone wanting to get the alerts to do so simply by subscribing to the service through
Twitter. The Twitter alert sent by ORC would notify the recipient, that in the council’s opinion, conditions could lead
to flooding. The alerts would direct the users to the ORC website (www.orc.govt.nz) to find out more detailed information on potential flood events.
Under the new system, flood information could be sent out more efficiently and effectively to a wider group of people
than previously, Dr Palmer said.
There will be two types of notifications “watches” (high river or lake level is possible within the next 36 hours) and
“warnings” (high river or lake level is likely or certain within the next 36 hours).
Dr Palmer said 36 hours was considered sufficient to give people time to prepare and respond to the flood, whilst
keeping the forecast period as short as possible.
ORC flood managers currently telephone people individually based on predefined triggers (river levels or flows at
indicator sites). ORC has 24 ring lists with a total of 430 contacts. The Twitter alerts and ring lists will operate
alongside one another in the meantime, until the new system is proven to meet ORC and community service requirements.
“Contacting the people on the ring lists is time-consuming,” Dr Palmer said. “The lists do not provide complete coverage
of flood-prone areas in Otago, or some of the areas that have the highest flood risk.”
“Moving to a Twitter-based alert system will free up our staff to assess, forecast, monitor, and respond to flood
situations; and release clear, concise, and timely information.”
Dr Palmer noted that several regional councils in NZ had either done away with ring lists, or were in the process of
doing so. The Canterbury earthquakes and the grounding of the Rena container ship off Tauranga had highlighted how
social media could connect people to resources, vital information, and each other.
In the case of Otago floods, the Twitter alert would act like a pager notification. Once people subscribed to the
service, which was free, they would automatically receive flood alert notifications until they unsubscribed from the
service. They did not need to subscribe every time there was a flood, and could unsubscribe whenever they wanted to.
Users of ORC’s website could also choose to connect to the WaterInfo website (for detailed, real-time hydrological data,
the Otago Natural Hazards Database, and the Otago Civil Defence Emergency Management (CDEM) Group website (for advice on
how to prepare, respond and recover from floods), Dr Palmer said.
ENDS