Oil Pollution Response overview
The oil pollution response components fit within Maritime NZ's wider National Maritime Response System. The vast majority of national-level oil pollution incidents will have an associated stricken vessel or offshore oil and gas installation – it is rare to have a significant oil spill that cannot be traced to a source. Therefore, for a national-level oil pollution response, the National Maritime Controller and National Maritime Response Team will be stood up, and the National On Scene Commander and the Maritime Emergency Coordination Centre responders will be deployed.
For an overview of the National Maritime Response System, how it is initiated, key roles, refer to the Maritime Incident Response overview.
Oil pollution response is managed using a three-tier system
Oil pollution response is managed using a three-tier system. The tiers describe the level of response, not the spill and are also applied to readiness activities.
Those responsible for each tier are required to prepare for and respond to an oil spill appropriate to their level of responsibility:
Tier 1 oil spill responses: the operator responds to and manages these oil pollution incidents (for example ships, offshore oil and gas installations, and oil transfer sites).
Tier 2 oil spill response: the regional response team, led by the Regional On-Scene Commander (ROSC), manages these oil pollution incidents
Tier 3 oil spill responses: the National Maritime Response System manages these national-level marine oil pollution incidents, led by the National On-Scene Commander.
There is an escalation process. The Regional On-Scene Commander can declare a Tier 2 response, where an operator's capability is exceeded. Similarly, the National On-Scene Commander can declare a Tier 3 response and manage any response that is beyond the capability of a regional response team.
If the scale of the incident is beyond New Zealand's domestic capability, arrangements are in place to secure overseas assistance.
New Zealand Marine Oil Spill Readiness and Response Strategy
National-level oil pollution response is guided by the New Zealand Marine Oil Spill Readiness and Response Strategy 2022-2026, and the National Marine Oil Spill Contingency Plan 2020.
Marine Oil Spill Contingency Plans
It is also a requirement for each regional council to have a Regional Marine Oil Spill Contingency Plan (RMOSCP) and for each operator of a ship or offshore installation to have a Shipboard Marine Oil Spill Contingency Plan (SMOSCP) or Offshore Installation Oil Spill Contingency Plan (OIOSCP), respectively.
The RMOSCPs hold valuable information that can be utilised in a national-level response, such as environmental sensitivities and preferred response options – and additional supporting information such as key contacts, regional assets and expert contractors.
Marine oil pollution response options
A marine oil pollution response must be undertaken safely and ensure oil removal activities cause minimum harm to the environment.
The overall approach to a marine oil pollution incident follows the ‘Cone of Response’ which illustrates the general cascade of priorities:
- source control – controlling the release of the oil at the source, or removing the oil from the vessel
- containment at the source – containing the oil, so that it cannot spread
- removing free floating oil – using booms and skimmers, or dispersant (if suitable)
- protecting shorelines from oil – using booms to stop the oil from hitting the shore
- shoreline cleanup – removing oil from the shoreline, using machinery or doing this manually with hand tools.
Due to safety concerns, weather conditions or equipment limitations, it may not be possible to control the incident using the primary priority action. In which case we assess the viability of the next option, and so on. In extreme situations, the only option that is available to the response is shoreline cleanup.
Natural recovery
If the spill is far enough from shore and unlikely to impact marine wildlife, it may be appropriate to allow oil to disperse naturally. The ocean contains bacteria that break down the oil. We would continue to monitor and assess the situation.
Dispersants
Dispersants are chemicals that help remove oil from the sea surface by breaking oil slicks into small droplets. The small droplets are then dispersed and diluted into the underlying seawater by wave action, where they are broken down by bacteria. The most known of the group is Oil Spill Control Agents or OSCAs. Only approved OSCAs can be applied to marine oil spills, and then only under specific circumstances and conditions.
For more information on dispersants:
Containment and recovery
Booms can be used to contain free-floating oil. Skimmers or sorbents can then be used to remove the oil from the water's surface. Once recovered, the oil is taken away for disposal.
Shoreline clean-up
Where oil has reached the shoreline, the team will assess the impacts of response activity in each area. Each intervention action must be measured against the option of natural recovery.
Prioritisation is important. For each sensitive area, several factors are included in a detailed analysis. These factors include ecological value, cultural significance, socio-economic value and recovery time.
Response personnel
We have approximately 150 National Response Team members and approximately 400 trained responders nationwide, many of whom are regional council staff, and members of the regional response team.
Maritime NZ staff will also be called upon to assist with a response, including for technical advice, legal advice and Public Information Management (PIM)
External support from national and international partners
External support from national and international partners and providers takes many forms. Examples include:
- locally contracted services for personnel, vessels, aircraft (fixed wing, heli and unmanned aerial vehicles) heavy machinery, waste management
- advisory services for offshore oil and gas incidents, maritime law, salvage and towing
- internationally contracted services for oil spill trajectory modelling (to determine where a water-borne spill is likely to travel)
- membership benefits with global response agencies, who provide response personnel and resources
- bilateral support agreements for responders and resources.
Cost recovery
Maritime NZ responds to oil spills under the premise that ‘the spiller pays’.
Response costs are claimed once the response has been terminated. The costs include those associated with responders for example time, travel, accommodation, PPE, specialist advisory services, equipment (rental and replacement, if required), consumables, contracted services.
National-level oil pollution incidents in New Zealand and beyond
Examples of marine oil pollution incidents that have required a national-level response (or have resulted in international support and cooperation) include:
- 2024 sinking and oil spill from the HMNZS Manawanui – Upolu, Samoa
- 2019 grounding and oil spill from the bulk carrier MV Solomon Trader on Rennell Island, Solomon Islands
- 2017 sinking and oil spill of the container vessel MV Southern Phoenix - Suva Harbour, Fiji
- 2011 grounding of the cargo vessel MV Rena off the Tauranga coast.
NZ Maritime NZ oil spill responders also supported our international partners at two offshore oil and gas incidents:
- 2010 Deepwater Horizon loss of well control and extensive oil spill in the Gulf of Mexico
- 2009 Montara loss of well control and subsequent oil spill in the Timor Sea.