Improving the health of the Waikanae estuary is very important, writes Chris Turver, from the Waikanae Estuary Whitebaiters Network, in this opinion piece

None of the three authorities responsible for the Waikanae estuary have denied it is dying nor put forward any initiatives to materially improve the deteriorating quality of its marine ecology and habitat.

The Waikanae Estuary Whitebaiters Network has now received Official Information Act responses from the Department of Conservation, Greater Wellington Regional Council and Kāpiti Coast District Council and they offer little comfort.

Apart from commendable long-running efforts by the Waikanae Estuary Care Group to revegetate the estuary boundaries with land-based plantings, no plans have been produced for removing the mud which is smothering marine life or restoring marine habitat.

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What emerged from our research was a story of neglect with an independent Broad Scale Habitat Mapping Report saying mud now smothers 54 per cent of the upper estuary, resulting in the loss of 100 per cent of seagrass on which many fish and wading birds feed. And through urban sprawl there is a 90 per cent loss of saltmarsh on the estuary margins which provides habitat and breeding cover and a 90 per cent loss of buffering vegetation which limits the runoff of sediments into the estuary.

Looming over the whole future of the estuary is a huge shingle build-up in the river at the upper end of the Scientific Reserve which future floodwaters will steadily wash further down into the estuary and destroy its ecological values forever.

This is supposed to be an iconic environmental showpiece and we had hoped the authorities would recognise the issues and show some urgent leadership in restoring the marine ecology of the estuary.

While the estuary might be a "special place which must be protected", there was not one word from any of the three authorities on:

■how the smothering mud will be dealt with to allow regeneration
■how the marine ecology will be restored
■how the inexorable march of the shingle will be stopped
■future planning to restore the estuary

In short, there is no regeneration plan and no evidence from the Official Information Act responses to demonstrate that the three authorities care enough to develop a plan. The only initiative is coming from the Kāpiti mayor who is planning a forum of interested parties, now next year.

The Department of Conservation has overall management responsibility for the Scientific Reserve which covers most the estuary but has offered no solutions in its Official Information Act response.

It does not deny a word of the independent Broad Scale Habitat Mapping Report's conclusions, and accepts that while "the estuary has degraded over time, with deforestation and urbanisation being the most likely causes", it claims "the overall condition of the estuary is considered to be moderate".

The Whitebaiters Network says DoC simply won't admit there is a serious problem even though the Habitat Mapping Report states unequivocally that "the ability of the estuary to assimilate sediment loads has now been exceeded" and "the upper estuary is expected to infill rapidly and become muddier and less biodiverse".

DoC is sticking its head in the sand and, as another example, it has so far refused applications by Greater Wellington Regional Council to remove shingle for river management purposes anywhere near its Scientific Reserve where the build up is occurring.

When two authorities like these can't work together on practical measures to both safeguard residents from flooding and manage effects on the estuary, there is something seriously wrong.

The Whitebaiters Network, which is prepared to support any practical initiatives to restore the health of the estuary, proposes an independent assessment of the causal effects and recommend solutions. We do this on the basis that the three authorities have basically abrogated their responsibilities by failing over many years to stop the slow death of a beautiful estuary.