Ammonia leak sparks evacuation

Ammonia leak at Cadburys Factory in Dunedin. Photo / Peter Mcintosh

A chemical spill closed streets and caused hundreds of people to be evacuated as central Dunedin ground to a halt yesterday.

Traffic was severely backed up on Dunedin's central city one-way system after an ammonia leak at Cadbury's Dunedin factory caused the evacuation of surrounding businesses.

Emergency services were alerted to the leak after an automatic alarm activated at 1.17pm.

Four appliances, a ladder truck and a command unit attended the incident and two firefighters in hazmat suits entered the factory with a Cadbury engineer to isolate the leak.

Fire Service Senior Station Officer Jason Hill, of Dunedin Central, said the "significant" leak led to the evacuation of Cadbury's central city facilities and nearby businesses in Castle and Cumberland Sts as small amounts of the gas leaked into the one-way system.

Both streets were closed from St Andrew St to Stuart St and Anzac Ave was also closed, causing traffic to back up for several blocks.

After firefighters isolated the leak, they ventilated the factory.

About 200 evacuated Cadbury workers had to wait for more than two hours before returning to the factory. Two tour parties in the factory at the time of the leak were forced to evacuate.

All roads reopened by about 4pm.

Cadbury's parent company, Mondelez, said the cause of the leak was under investigation.

The ammonia was used as a cleaning agent within the factory.