Stu Farrant, Southern Sector Manager
As parts of New Zealand bask in the tail end of our much anticipated El Nino summer, it is worth thinking about the implications for future stormwater management. With Wellington experiencing close to three weeks without a drop of rain (and only 6 mm in the past month), it is easy to concentrate on time at the beach and the wilting vege patch. But rather it is worth reflecting on what this means for the future of urban water management and the true impact of landuse on the environment.
At a time when flows in our rivers and streams are already low, and the incidence of potentially toxic algal blooms is making headlines, there is a build-up of a cocktail of contaminants on roads, carparks, driveways and roofs, ready to be discharged as a plug come the next rain event. This uncharacteristically concentrated discharge will result in acute impacts on receiving ecosystems which exceed most predictive models and historical water quality data.
With predictions for climate change to result in longer dry spells interspersed with high intensity rain, it gives us a clear reminder of the criticality of treating urban runoff and delivering resilient systems which can respond to these changing climatic conditions. It also provides impetus to recognise the true value of stormwater as a resource and deliver integrated water management solutions founded on alternative water sources and stormwater harvesting to support fit for purpose reuse. An awareness of the impacts and opportunities of our changing climate needs to drive innovative solutions to protect urban ecologies, support community health and wellbeing and provide for a more resilient future.