On Thursday night I hosted a great swimmable rivers meeting organised by the local Greens in Heretaunga (Hutt Valley). It was great to see about 70 people attend and engage in the topic. We were welcomed by Te Atiawa representative Ihaia Puketapu, who also spoke passionately about collective responsibility for ending consumerism and protecting our natural world. His mihi informed us about the origin of the names of the river and land forms, and the connections to other parts of the motu.
The second speaker was Mark Heath, a freshwater scientist from Greater Wellington Regional Council whose PHD was on toxic algae blooms in the region and this river. His presentation was extremely informative and showed the complexities of the topic. At times toxic algae (Cyanobacteria) can cover up to 70% of a section of the river. The causes are multiple and the science somewhat counterintuitive. Toxic algae seem to thrive where there is low phosphorus and high sediment and varying levels of nutrients.
We learned that the river is impacted by urban stormwater and sewage overflows, heavily fertilised golf courses and parks, leaking septic tanks and more. This combination of factors can have serious effects. It was clear from the meeting that swimming and walking the dog is a risky activity along parts of the river at some times of the year. The meeting had a great discussion about how we can improve urban design and agriculture to clean up rivers. There were many questions about the risks of swimming in the river. A number of active local groups were represented and I urged people to join in and help with the practical and political work to improve the situation. I also urged them to change the Government if they want clean water! Swimmable rivers is an urban goal as well as a rural one, and everyone supports it except the National Party.