How the system works & Disclaimer

Receiving Greater Wellington (GW) flood warnings is an advisory service, and GW does not accept responsibility for any losses incurred due to flooding. GW expressly disclaims any liability for any failure of the service to deliver notifications or otherwise function as intended, as well as for any actions taken or not taken by recipients based on the receipt or non-receipt of a warning.

However, we strongly advise users to take these warnings seriously and to take appropriate measures to protect themselves and their property in the event of a flood. We also recommend monitoring weather forecasts, current conditions and taking any necessary precautions.

What system is GW using to implement flood warnings?

GW is using a Software as a Service (SaaS) system provided by TNZ Group Limited to implement flood warnings. This New Zealand-born company specializes in message delivery technology, streamlining business communications worldwide. For more information, please visit the TNZ Group Limited website.

What is the flood warnings process?

The GW Forecast and Warning Duty Officer (FWDO) receives a river or rainfall alarm via the GW telemetry system. Using the TNZ system, a template message is sent in Interactive Voice Response (IVR) format to assigned recipient’s mobile phone and/or landline. The TNZ system enables FWDOs to efficiently distribute flood warnings, ensuring the timely and accurate delivery of flood information, thereby protecting both people and property in the region.

During a flood, FWDOs won't track individuals’ interactions, but will be used for system analysis later. The FWDOs will no longer be making or receiving phone calls regarding flooding.

How does the system work?

  • If the FWDO receives a telemetry alarm, they manually send a IVR through the TNZ system to all associated clients.
  • The client will receive the IVR phone call from the flood warnings line (04 915 2777).
  • Each client provides up to 9 phone numbers (main and 8 alternatives).
  • Clients are requested to answer the IVR phone call with 'Hello' even though they are aware it is an automated IVR. This ensures the system functions efficiently by distinguishing between a human response and an answering machine.
  • Each number provided is called up to 3 times, with the system checking for invalid numbers. It leaves a short message on the answer machine once (if encountered) and calls back every 2 minutes for failed transmissions.
  • If the client answers, the IVR will play 2 or more times based on their keypad interactions.
  • If the client presses an invalid keypad (‘3’ to ‘9’ or ‘*’ or ‘0’ or ‘#’) or a valid keypad (‘1’), the IVR restarts.
  • A successful transmission is when the client pushes ‘2’ on the keypad (confirming they have received the IVR) or ‘1’ on the keypad during the call. Pressing ‘2’ on the keypad stops the IVR, and the TNZ system responds with “Great, thank you for confirming. Please pass this message on” and ends the call.
  • A failed transmission is when the client hangs up, presses only invalid keypads (‘3’ to ‘9’ or ‘*’ or ‘0’ or ‘#’) or doesn’t press any keypads.
  • For questions or feedback, the client can call the flood warnings (04 915 2777) and leave a detailed message.

What information will be stored on TNZ’s SaaS system?

  • All information provided in the registration page.
  • All registration page and TNZ system interactions.
  • All information collected regarding message recipient consent will be retained for a period of two (2) years from the date each message is sent.

Please see our privacy statement for more information.

GWRC Flood Warning