Waikanae River

Mayor Welcomes Greater Wellington’s $80k Investment in Waikanae River

Statement by Kapiti Coast District Mayor K Gurunathan


I welcome Greater Wellington's announcement of an $80k investment to remove 3000 cubic meters of wet gravel from the Waikanae River in the vicinity of the Expressway bridge. The rationale that this will reduce the risk of flooding on neighbouring properties is a prudent one. What has not been highlighted is that this will prevent this material eventually moving further downstream to adversely affect the vulnerable ecology of the Waikanae Estuary Scientific Reserve. 

I would hasten to alert GW regional council and DOC that this announcement will, without a doubt, trigger calls by others, and especially the vocal Waikanae Estuary Whitebaiters Network, for similar work to remove the gravel and sedimentation at the mouth of the river. The Network has long argued that this build up plugs the mouth and increases the potential for flooding upstream. They have argued that this build up has continued to degrade the environmental quality and biodiversity of the Estuary which is a classified Scientific Reserve deserving very high protection.  

The project is jointly funded by NZTA, M2PP Alliance and GW because the build up is directly related to the widening for the Expressway bridge in 2016. I welcome the removal of the 3000 tonnes of upstream material as that will mean this material will not move, over many years, downstream to further damage the Estuary.  

Given the consenting process, which would have needed DoC support, has successfully resulted in this project going ahead the question raised by the Whitebaiters Network remains to be answered. They have said that since 2007 discussions between GW and DOC to remove wet gravel from the Estuary area has not succeeded. Given this week's announcement will GW and Doc review the situation at the Estuary?


High levels of toxic algae found in Waikanae River

Waikanae River Bridge - Photo Tony Cutting

Waikanae River Bridge - Photo Tony Cutting

Greater Wellington Regional Council is advising people not to swim or walk dogs off-lead in and around the Waikanae River below SH1 due to high levels of toxic algae. 

Latest assessments show that toxic algae exceed safe levels in the river west of SH1, where river stones are covered and detached mats have been seen. 

“With continuing warm weather and a dry spell, we are seeing late season growth, so we are urging people to be careful near the Waikanae River in particular, says Dr Mark Heath, Senior Environmental Scientist at Greater Wellington.” 

Toxic algae are below warning levels in all other monitored waterways throughout the region. 

Given the rapid growth of toxic algae, and its potential change in coverage between weekly monitoring points, people are also urged to be able to recognise and avoid it. They should check out information signs around popular swimming holes and visit Greater Wellington’s Is it Safe to Swim? website and Facebook page for more information about, and images of, toxic algae. 

Toxic algae grow on submerged river stones in a shiny brown/dark green coating. When it dies it floats to the surface and forms small brown mats at the water’s edge. It is important to keep an eye on babies and toddlers who are inclined to put objects in their mouths, and dogs are naturally drawn to its odour. Anyone who swallows toxic algae should seek medical attention.

-Greater Wellington Regional Council