Local Govt | National News Video | Parliament Headlines | Politics Headlines | Search

 


Important Porirua Harbour habitats at risk

Important Porirua Harbour habitats at risk


The results of a recent survey show sediment entering the harbour continues to be a problem in Porirua Harbour.

The latest five-yearly survey of Porirua Harbour intertidal habitats has shown that the area of estuary covered in freshly deposited mud has increased substantially, particularly near the Kakaho and Horokiri streams.

Soft mud reduces the water clarity, the amount of oxygen in the sediment, and the growth of vital seagrass. This results in a loss of habitat, reduces recreational and aesthetic values and the estuary’s ability to function effectively.

The density of seaweed growth near the mouths of the Porirua, Pauatahanui and Horokiri streams is evidence that nutrient inputs (nitrogen and phosphorus) remain high. Seaweed mats can smother sediment and seagrass. When the seaweed dies it starves the sediment of oxygen and causes black smelly mud.

Although there are large, healthy areas of saltmarsh in the eastern Pauatahanui Arm, saltmarsh is absent in the Onepoto Arm of the harbour. Saltmarsh areas are highly productive, provide valuable habitat for fish and birds, and offer flood and erosion protection.

“Though this is only the second habitat mapping survey in Porirua Harbour, the findings confirm that important habitats such as seagrass and saltmarsh remain vulnerable to the effects of human activities on land” says Greater Wellington Regional Council’s Coastal Scientist, Dr Megan Oliver.

“Sediment and nutrient inputs from the surrounding land and waterways are reducing sediment quality, biodiversity and healthy functioning of the estuary”.

The Regional Council commissioned the second broad scale habitat mapping survey of the intertidal area to assess the changes in key estuary habitats (eg, saltmarsh and seagrass) and substrate (e.g. areas of mud and sand).

The information has been gathered as part of the Regional Council’s State of the Environment Monitoring requirements under the Resource Management Act.
Information from the report will feed into the Porirua Harbour and Catchment Strategy and Action Plan’s sediment reduction and estuary restoration work and help focus policy and management decisions related to land-based activities.

The Strategy and Action Plan is a council and community project that has been prepared and adopted by four key stakeholders – Te Runanga o Toa Rangatira, Porirua City Council, Wellington City Council and Greater Wellington Regional Council - along with 10 other agencies. A new joint committee of the four organisations is now being set up to work more closely and to oversee the implementation of the strategy.

Ngati Toa Rangatira kaumatuaTaku Parai says it’s good that the regional council is closely scrutinising the condition of the harbour to ensure everyone is aware of these issues and helps to turn them around.

“Loss of significant habitat in the harbour is a problem that has affected Ngāti Toa for many generations. Having access to the information provided by these surveys is empowering for iwi and the whole community to work together for positive change,” says Mr Parai.

The issues arising from the survey are being addressed as part of the harbour strategy.

Porirua Mayor Nick Leggett and Regional Councillor Barbara Donaldson point out that a lot of work is happening including sewer and stormwater upgrades, community education, the development of an estuary restoration and catchment revegetation framework, research and a review of the region’s regulations
Work on a catchment erosion control plan will be completed in February followed by its implementation. This, along with improved earthworks control, will have an impact on reducing sediment entering the harbour. It’s also a reminder to the community that re-vegetation of the catchment is one of the most significant things we all can push to reduce sedimentation.

Over summer, the regional council will be carrying out routine annual measurements of sedimentation in the harbour. There are also plans to undertake habitat mapping of the subtidal areas of the harbour.

The report can be downloaded from the document library on GWRC’s website – search for “Porirua Harbour broad scale survey” or visit http://www.pcc.govt.nz/Publications/Porirua-Harbour-and-Catchment-Management-Programme

ENDS

© Scoop Media

 
 
 
 
 
Parliament Headlines | Politics Headlines | Regional Headlines

Joint Statement: Establishment Of NZ-China Strategic Partnership

At the invitation of Governor-General Lt Gen The Rt Hon Sir Jerry Mateparae and Prime Minister The Rt Hon John Key of New Zealand, President Xi Jinping of the People’s Republic of China made a state visit to New Zealand from 19 to 21 November 2014.

During his visit, President Xi Jinping met with Governor-General Jerry Mateparae, and held talks with Prime Minister John Key. The leaders had an in-depth exchange of views on bilateral relations as well as regional and international issues of common interest. More>>

 
 

Parliament Today:

Savings Targets: Health Procurement Plan Changes Direction

Next steps in implementing DHB shared services programme Health Minister Jonathan Coleman says the Government has agreed to explore a proposal put forward by DHBs to move implementation of the shared services programme to a DHB-owned vehicle. More>>

ALSO:

More on Health Policy:

Auckland Unification: 'No IT Cost Blowout' (Just More Expensive)

Following discussion of an update on Auckland Council’s Information Services Transformational Programme at today’s Finance and Performance Committee, council has released the report publicly. More>>

ALSO:

Other Expensive Things:

Gordon Campbell: On The SAS Role Against Islamic State, And Podemos

Only 25% of the US bombing runs are even managing to locate IS targets worth bombing. As the NYT explains at length, this underlines the need for better on-the-ground intelligence to direct the air campaign to where the bad guys have holed up... More>>

ALSO:

Public Service: Commission Calls For Answers On Handling Of CERA Harassment

EEO Commissioner Dr Jackie Blue is deeply concerned about the way in which the State Services Commission has handled sexual allegations made against CERA chief executive Roger Sutton this week and is calling for answers. More>>

ALSO:

Gordon Campbell:
On Andrew Little’s Victory

So Andrew Little has won the leadership – by the narrowest possible margin – from Grant Robertson, and has already been depicted by commentators as being simultaneously (a) the creature of the trade unions and (b) the most centrist of the four candidates, which would be an interesting trick to see someone try in a game of Twister. More>>

ALSO:

China President Wishlists: Greens Welcome Xi, But Human Rights Need To Be On Agenda

“President Xi has made some progress on climate change, but he must also lift the Chinese government’s game on human rights issues,” Green Party Co-leader Dr Russel Norman said... It is important that our Government continues to urge the Chinese government to show restraint and respect human rights in both Tibet and the Xinjiang province.” More>>

ALSO:

Airport Security Breach: CAA Fines Minister

Minister Brownlee has been issued an infringement notice and is required to pay a $2000 infringement fine for breaching Civil Aviation Rule 19.357(b), which states no person may be in an airport security area without an appropriate identity card or document. More>>

ALSO:

Get More From Scoop

 

LATEST HEADLINES

 
 
 
 
 
 
 
 
Regional
Search Scoop  
 
 
Powered by Vodafone
NZ independent news