A major oil spill exercise is due to be held on the Coromandel next month, taking into account lessons learned during the Rena disaster.
The Waikato Regional Council exercise – involving up to 30 staff and including supporting agencies – will trial the use of booms to check their effectiveness in helping keep oil out of environmentally sensitive Coromandel sites.
The exercise will begin at Whangamata harbour on 12 June and may also include the Otahu estuary and Opoutere harbour, depending on progress with the booming trials.
Non-toxic sawdust may be used to simulate oil floating on the water, although a final decision on this is yet to be made.
Regional on scene commander Adam Munro said the council’s annual marine spill exercise was normally held over a day at one location, and was designed to deal with the effects of a spill inside a harbour.
“This year, following on from the Rena disaster, we’re exercising up to three days and up to three locations with a view to helping keep oil from a big spill out of the two harbours and the estuary.
“This will simulate a situation where oil is threatening multiple locations over an extended period, a scenario similar to that which affected the Bay of Plenty after the Rena grounding.”
During that time, the council and Maritime New Zealand developed a series of site specific response plans when it was predicted that oil from the Rena would impact the Coromandel’s east coast.
The narrow entrances to some Coromandel harbour and estuary areas meant there may be a good chance of using booms to help block them off from spills out to sea. However, these narrow entrances also created a number of challenges, including fast flowing tidal currents and limited access points.
“Because of potential impacts to these important and vulnerable environments every effort should be made to redirect and recover oil before it enters the upper areas of harbours and estuaries, thereby minimizing environmental damage and recovery cost,” said Mr Munro.
“Should a big spill again threaten our region we want to see if our planning, and Maritime NZ’s equipment that we use, is up to the task of protecting these environments using blocking booms to keep out as much oil as possible.”
He said the exercise – which may involve limited restrictions on boats using the trial areas - will take into account the recommendations of a post-Rena Maritime NZ report on the use of booms to protect Whangamata, Otahu and Opoutere.
Mr Munro noted that in the event of a big spill it may not be possible to protect every threatened site using booms and sites would have to be prioritised accordingly.
“This exercise will be a good opportunity to work with supporting agencies and to judge whether our current equipment is adequate for a range of scenarios.
“If we think more or different equipment is needed, we’ll make recommendations on this to Maritime NZ,” said Mr Munro.