No time for diluted ambitions

Dramatic changes in the water cycle mean we can no longer go with the flow.

Water; too much, too little, too polluted, too taken for granted? We’ve seen the reports of flooding in New South Wales, Australia in recent weeks, and the deaths. Auckland has just been hit by flash floods after severe thunderstorms. We’ve experienced our share of flooding in Otepoti Dunedin in recent years and will again. But in Southland there’s drought and in Otago we’re drawing excessively from our waterways. The Manuherikia is not only a river cutting through Central Otago; it is also a contest between nature and the economy, and is in decline.

Meanwhile many of our wonderful glaciers will be gone this decade, as ice melt gathers pace. Water is essential for life. And yet too much in the wrong place and not enough in the right place puts us all at risk.

Adapting to an uncertain future will require a new relationship with water in both urban and rural communities. To restore the health of the Manuherikia, for example, the river flow must increase. First and foremost we must recognise the health, or mana, of the water as described in the 2020 National Policy Statement for Freshwater. To do so will require some farmers giving up constant irrigation and return to dryland farming with reasonable support to do so.

Water in the urban setting of Otepoti Dunedin is more complex because we are having to think seriously about urban design in an already well-established city. Yet there is a large body of work now, globally, on the concept of "blue-green" cities: cities, in other words that bring water management and green infrastructure together. The urban space can be made "softer" with permeable surfaces, rather than concrete, and rainwater capture to soften and manage downpour events. The provision of water-holding features in South Dunedin — using Forbury Park, Bathgate Park and Tonga Park — could reduce flooding risk to surrounding homes and deliver flood resiliency.

Water-sensitive urban design must take into account changing coastlines as well, of course, and the St Clair-St Kilda Coastal Plan, the result of years of community engagement, was adopted by the Dunedin City Council in February 2022. An adaptive management approach has been proposed, with use of nature-based solutions including coastal set-back as conditions change.

Where and what we build matters. If we build new homes on Forbury Park, for example, we’ll be reducing flood protection and increasing flood risk alongside the risk of more drowned assets. If we allow excessive irrigation draw from the Manuherikia, it will become less of a river, and more of a "pea and ham soup" as archaeologist Matthew Sole describes it. We can no longer afford the extractive exploitation of our freshwater. Aukaha chairman Edward Ellison expressed it best last August when he said, "We’re looking to get an outcome that reinstates the mauri, that gives us the opportunity to have mahinga kai — that connection our people sense and feel when they see and touch that river that it’s close to reflecting a natural state."

The climate crisis makes clear that we can no longer consider these issues in silos. We need to think and plan in an integrated, holistic way.

The National Adaptation Plan is anticipated to be released in August this year. It will consider hazard in all its guises and we can be sure that water, as coastal inundation risk, as flood risk, as risk from extreme storm events, and as an absence in dry, drought prone parts of the country, will feature strongly.

So let’s not water down ambition. I want to see support for farm transitions with thriving rural communities and "blue-green" urban design to meet the scale of the challenges ahead. I want to see leaders demonstrating ambition, not incrementalism.

Scott Willis is a climate and energy consultant. Each week in this column one of a panel of writers addresses issues of sustainability.