Gravel build-up changes river
Dramatic changes in the Waikanae river are illustrated in before-and-after photographs showing the effects of gravel build-up in the lower reaches which have degraded the picturesque river, Waikanae Estuary Whitebaiters Network steering committee chairman Chris Turver said.
“The first, taken in 1959, shows the river was navigable by quite large boats from the sea to upstream of O¯ taihanga Boating Club, with some moored in the middle of the river and others against the banks.
“The second in 2018 shows the restricted flow of the river from rising shingle banks which have made boat access impossible and reduced the value of the twice daily tidal flushing effect for marine life.
“The Department of Conservation listed the Waikanae river in March as one of the 14 most degraded waterways in the country which are to get remedial funding, but it won’t stop the shingle buildup.”
He said two factors had significantly changed the river.
“The first was the establishment in 1987 of the DoC’s Scientific Reserve which covers the entire estuary from just downstream of O¯ taihanga Boating Club to the sea.
“The second was the 1991 Resource Management Act which can be used to prevent shingle extraction on the grounds it disturbs the biota and fish life of the river bed.
“DoC has refused shingle extraction in the Scientific Reserve since 2007.”
Mr Turver said it’s bad enough that the lower river is no longer navigable but public safety is threatened by worsening flood risk, unchecked sedimentation is smothering the estuary, and the movement of biota and fish life between the sea and the river is increasingly restricted.
“The Whitebaiters Network has several times called on DoC to allow removal of shingle by Greater Wellington Regional Council but there has been no response.
“The damning result is that the lower river and estuary have been so degraded that DoC itself, in response to an Official Information Act request, has admitted that in terms of the environmental values it sets for all its assets around the country, it can only rank Waikanae estuary at 759th compared with neighbouring Ka¯ piti Island on 21.”
Department of Conservation responds:
“The department has not received any applications for shingle extract from the Scientific Reserve,” Jack Mace said. “Any application would be considered under the Reserves Act 1977, which states how scientific reserves such as the Waikanae Estuary Scientific Reserve must be managed. References to DoC listing the Waikanae Estuary as degraded are incorrect and misinterpret our ranking for the Estuary.
“The estuary has been given a ‘high’ assessment by DoC in terms of ecological value and numbers of threatened and atrisk species, and is second highest in those rankings for the Lower North Island (Estuarine systems in the lower North Island/Te Ika-a-Ma¯ ui, DoC 2016).”
On March 5 Waikanae River was chosen as one of 14 priority river catchments for restoration. This is due to its high natural values, and a strong drive from iwi and the community to restore and look after the river.”