Nelson City Council is working to improve flood protection along the Maitai/Mahitahi River from Hanby Park to the end of Clouston Terrace.

Tonkin & Taylor has started to develop the concept design options for the section alongside Clouston Terrace, from the bridge to the end of the road.

We are seeking feedback from residents on these options before we move into preliminary design.

We currently are proposing the following:

• Cut back/down the existing stopbank to give the river more room to flow, under Clouston Bridge and next to Clouston Terrace.
• Build a floodwall on the landward side of the stopbank, designed to handle a 1-in-100-year flood (larger than the August 2022 storm).

Options for Clouston Terrace:

There are three options to achieve what is proposed. The key difference between the options is the height of the floodwall relative to the road:

Option 1 – Keep the road at its current level. At its highest, the floodwall would be up to 2.6 m above the road – a significant visual barrier between the road and the river.

Option 2a – Raise the road (with retaining walls). Raising the road means the wall only needs to be about 1.2 – 1.5 m above road level, so you can still see the river. Retaining walls would be used at property boundaries, with driveways sloped to meet the higher road.

Option 2b – Raise the road (with sloped embankments). Same as 2a, but instead of retaining walls, the ground within private property would be sloped to meet the raised road.

During detailed design we’ll look at the specific parts of Clouston Terrace that may be raised, reducing both the extent (length) of road raising and its height increase.

Other things to know

• Road width: The trafficked area of Clouston Terrace would narrow from about 5 m to 3.5 m. We’ll consider impacts on rubbish collection and vehicle turning during detailed design.
• Footpath access: The floodwall will change how you get to the riverside footpath. Access from Nile Street (downstream side of the bridge) may not be possible, but we’ll look at whether it can be kept during detailed design.
• Vegetation: Construction will remove most vegetation along the bank, including the two oak trees near the bridge. Replanting is part of the design, including a 1 m planted buffer on the road side of the wall (possibly in planter boxes).
• Wall design: The floodwall would likely be concrete, with the potential to incorporate art for visual and cultural amenity.

Design drawings and more detail

Detailed plan views and cross-sections showing each option are available here. These drawings show what each option would look like at four locations along Clouston Terrace.

Have your say

We’re moving from conceptual design to preliminary design, where we’ll develop enough detail to apply for resource consent. Your feedback will help shape that next stage.

Please send your comments to Engage@ncc.govt.nz by 15 April 2026, or fill in the form below.

If you have questions or would like an in-person chat, then please get in touch at the above email or call 03 546 0200 – we’re happy to help.