Mangrove Removal Bill – Futile and Flawed

Local Mangrove Removal Bill Takes Chainsaw To Legal Rights

For over a decade a debate has raged in some local communities between those who regard mangroves as an invasive weed and others who appreciate their ecological role as coastal nurseries. Now the Thames-Coromandel and Hauraki District Councils want a local Bill passed in Parliament for the sole purpose of enabling mangrove removal. One law just for mangroves and one law for everything else? 

The Bill absurdly attempts to nullify the Resource Management Act and all other laws controlling mangroves. Pardon? Really?  This is not a serious and credible effort to resolve the issues.  Instead, it has the hallmarks of a populist but futile attempt to appear to be “doing something”?  

The “weed” versus “nursery” arguments have been well rehearsed.  But the vital role mangroves play as a natural shield against storm tide surges, erosion, and sea-level rise has largely been ignored.  

Mangroves have been well proven to be a very effective defence against storm tides and erosion because they dissipate wave energy.  Farmers next to the Hauraki Plains coast with has a fringe of protective mangroves reported little wave action during cyclone Drena in 1997.  Drena caused over $3 million of damage to Moanataiari suburb in Thames which had a sea wall.

The Parliamentary Commissioner for the Environment has confirmed that extremely damaging storm tides such as Drena, which are currently 1-in-100 year events, will occur every year with just 0.5 m of sea level rise.  0.5 m of sea level rise is certain, the only uncertainty is how soon. 

half M rise ann event Parl Comm

The Lower Firth already has New Zealand’s highest ever recorded storm tide rise of 1m.  Storm tides and currents are often intensified in harbours and estuaries. 

 A Waikato Regional Council  Report on Mangroves in the Lower Firth of Thames had this conclusion in the Executive Summary:

“Coastal hazards mitigation

The mangrove forest provides a number of ecosystem services, which mitigate the potential coastal erosion and inundation hazards that exist for the low-lying Hauraki Plains. 

 The present-day mangrove forest provides a high level of protection to the stopbank from wave-induced coastal erosion”

The Councils are already being pressured by coastal property owners to provide “hard” barriers against coastal erosion and flooding.  A quick review of the maps on Councils coastal hazard website will confirm that many of the very same areas at most risk from storm tides and tsunami have a protective mangrove fringe.

It is nonsensical to tear out a highly effective natural barrier against storm tides, erosion, and sea level rise only to then replace it with a hugely expensive and ineffectual wall or other “hard” structure.

To a lesser extent mangroves also provide some measure of protection against a tsunami. Numerous studies following the Christmas Day tsunami in 2004 showed that places with mangrove protection suffered much lower loss of life, and damage to property than areas with no mangroves.  Mangroves are trees so they are also a great resource to sequester carbon and help reduce co2 emissions.

One of the arguments advanced for the local Bill is the loss of habitat in the Firth of Thames for godwits and other birds due to the expansion of the mangroves.  The Auckland Unitary Plan already has a provision, using existing laws to allow mangrove removal in areas where bird habitat has been affected. There is no need for special legislation to achieve that objective. In any case, the threat to birdlife from mangrove expansion seems to be greatly overstated. A Waikato Regional Council risk assessment of the environmental and other threats to Miranda/Firth RAMSAR reserve showed that agricultural land use (dairy), sedimentation, climate change, and urban and industrial use all posed much greater threats than mangroves.  But of course, we won’t be seeing the Councils promoting special local laws to tackle those issues.

relative risk RAMSAR

Under the proposed new Bill every other existing law which controls mangrove management – including the Resource Management Act –  would be swept aside.

Mangrove removal would be placed on a pedestal with a unique legal privilege not given to any other activity.  The right to a hearing before an independent commissioner or the Courts would be ditched.  Instead, the Councils including some members who have already prejudged that mangrove removal should occur, would merely “consult”.  There is no right of appeal – the Council would have the final say – kangaroo court anyone?

Our laws require every person or Council wishing to carry out an activity of similar scale to obtain a resource consent.  Imagine the huge outcry all around the country if this Bill were ever to be passed. 

Every man and his dog, and every other Council would be demanding special legislation for their pet project because they too were “frustrated by the time, cost and process”. Legal chaos would ensue.  The Bill has zero chance of becoming law.

The Councils should abandon this futile and flawed proposal.  To avoid being an embarrassing laughingstock – please go back to working through the existing Tairua and Whangamata resource consents (removal was halted due to failure to comply with the conditions), collaborate with the Regional Council under the 2016  agreed Statement of Intent, and comply with the laws which apply to everyone else.