“Traditionally, the first step in creating a new built environment was to get rid of the water,” says Liam Foster, WSP Kaiarataki Hangarau - Wai (Technical Principal – Water).
“Drain the swamp, push the river into a culvert. Create a platform and build a city.”
The value of water, if it was considered at all, often lay solely in its ability to transport waste. The degeneration of Waihorotiu, the stream that once ran down the valley now occupied by Auckland’s Queen Street, from tidal creek to open drain to sewer, is just one example of many lost urban waterways across Aotearoa New Zealand.
Source: Auckland Conventions
New Zealand’s fast-growing and urbanised population and changing climate means that urban designers need to look beyond the 10-year plan and take a broader view.
Climate change and peak impermeability (where water can’t enter the soil because of being ‘concreted’ over) are forcing developers and consenting authorities to confront the limitations of existing design criteria. Extreme weather events look likely to occur more frequently and to greater effect.
“You can try to control nature – up to a point,” says Liam.
“But ultimately the water will go where it wants. Any artificial design solution has its limits and the more artifice you employ the greater the consequences can be when those limits are exceeded.”
Water catchment areas are an ideal context in which to frame the water-led development approach, but it tends not to align with existing land ownership or administrative boundaries.
“Piping water out of its catchment area simply creates problems elsewhere," he says.
“Developing a catchment that can still function properly so that rainwater either soaks into the soil, is stored temporarily in appropriate areas or enters a creek network, will reduce the risk of flooding. An open stream will always have more capacity and greater flexibility than any buried engineered structure. The approach also improves the health of the waterways, and boosts plant and animal biodiversity and our connection with our natural environments.”
Liam believes that taking a water-led approach that gives the first right of water to water itself (as framed within the recent National Policy Statement on Freshwater Management 2020), is our only viable approach moving forwards. Regenerative urban development (in which water management plays a critical role) enables social and cultural benefits for communities and contributes to greater business and community resilience.
It will also go a long way to helping us improve and restore the mauri of our water environments in line with the industry shift to prioritising Te Mana o te Wai (NPS-FM 2020).
We all have a part to play in helping to recognise the interests, values, and vulnerabilities of historically marginalised communities and our waterways, by including those communities in decision-making and planning, and distributing the benefits and costs of proposed adaptation interventions in a more fair and equitable manner.
“A healthy water network provides significant aesthetic and recreational benefits for people living around it. It creates a community focal point, somewhere people can connect with each other, such as recent water sensitive designs delivered by WSP for Daldy and Halsey Street in Auckland. Here the WSP team focused on integrating a comprehensive stormwater management system into the public urban realm, overcoming significant engineering constraints associated with the site and its former contaminated uses. This water-led approach in turn helped to create a shared local identity for an iconic, high profile urban environment and to help showcase and unlock the amazing transformation of the Wynyard quarter,” says Liam.