Mills Street stopbank
Mills Street stopbank
Stage 1 of the Mills Street stopbank upgrade has been successfully completed, and we are proceeding with further enhancements to strengthen flood defences for the Hutt Valley.
Check out this animation showing how we’ve improved the flood protection standard.
The upgraded stopbank provides protection from an approximately 1-in-200 year flood. There’s a 0.5% chance of a flood that size happening in any year.
Greater Wellington built this stopbank to provide urgent flood protection for the community. Some sections were temporarily constructed around high voltage power cables, which are due to be moved in early-mid 2025. When this happens, Greater Wellington will finish the permanent stopbank – this will be Stage 2. We plan to complete the permanent stopbank by the end of the 2025/26 construction season.
Check out this video made while the stopbank was being upgraded.
We have used advanced engineering techniques to withstand flood conditions – they are not just piles of dirt. Despite this, there’s still a risk that any stopbank could be overtopped or breached in a massive flood. Check out Greater Wellington’s flood hazard advice.
River & rock works
The new stopbank is close to the river, and is vulnerable to erosion, so further river works are needed to protect it and the other surrounding assets.
We’ll be placing up to 1,000m of rock lines at key points along the river between Melling Bridge and Kennedy Good Bridge. Rock lines are sloping walls which protect the river bank from erosion. They will be built using the rock which is stockpiled along Harcourt Werry Drive. Some willows will need to be removed in these areas.
We’ll also be shaping the river and planting trees. Our ‘bioengineering’ approach will allow the river to flow in a more natural meandering pattern. It will involve burying willow trees (that we’ve removed for the rock line construction) to stabilise the banks. A mixture of natives and willow poles (which grow into willow trees) will then be planted, and eventually the willow trees will be phased out.
Check out this video showing how we’re going to do it.
We’re engaging contractors now, and the first part of this work to move the willows from the rock line sites is likely to start in November.
Trail closure
The eastern side of the Hutt River Trail between Melling Link Bridge and Kennedy Good Bridge will remain closed to walkers and cyclists to enable us to carry out the bioengineering and rock works.
Haul roads and work areas established for the stopbank upgrade will need to be used for the rock and river works.
The site has considerable hazards, such as unstable rock piles and uneven surfaces. We are committed to working to reopen the trail as soon as it is feasible.
Trail users will need to continue following alternative routes. It’s likely that trail closures, on either the eastern or western sides, will be in place until Te Wai Takamori o Te Awa Kairangi programme is completed. We appreciate your patience and cooperation while we undertake this important work.
Working with Mana Whenua
Our programme partnership enables Mana Whenua to work with Greater Wellington to achieve Ora Tāngata (Health of People) Ora Taiao (Health of the Environment) and Ora Wairua (Spiritual Wellbeing). Our procurement criteria will include broader social outcomes and businesses bidding for contracts must show how they will achieve positive social impact for the local community.
We’re working together to develop, implement and monitor best practice holistic care for the river. Construction activities often have environmental consequences. Our flood protection work is managed so that the river can exhibit a more natural form, and so we can include opportunities for positive design, such as regenerating native plants along the river edge and acknowledging sites of cultural significance.
We will continue to monitor earthworks around Maraenuku Pā and ensure that Mana Whenua are involved in the management of archaeological discoveries. The river berms could still hold some taonga (treasures) of the past.
In previous work in Te Awa Kairangi / Hutt River, a partially carved waka was discovered.
Maraenuku Pā
North of the Melling Bridge and within the construction area of the Mills Street stopbank is Maraenuku Pā. The pā (settlement) is an area of cultural significance to Mana Whenua and was located in the vicinity of the electricity substation on Connolly Street.
It was established in the period 1839 to 1846, prior to colonisation, by Ngāti Tama from Taranaki and Ngāti Rangatahi from Ōhura (upper Whanganui River) who were closely allied to Ngāti Toa leader Te Rangihaeata.
Maraenuku Pā was built, and gardens were established even as shiploads of European settlers started to arrive in the Hutt Valley to take up blocks of land they had purchased in London from the New Zealand Company.
The sections purchased by John Boulcott were occupied by his son, who started trying to farm the land. This was close to, and part of the land occupied by Ngāti Rangatahi and in proximity to Maraenuku Pā.
The pressure on areas settled by Māori pā increased and through 1844, Ngāti Tama and Ngāti Rangatahi went on the offensive to protect the land they claimed.
The disputes for the land culminated in what became known as the Battle of Boulcott Farm and those associated with the pā were forced out. Maraenuku pā was demolished by British troops on 27 February 1846.
While no trace of the pā remains today, the history of Maraenuku Pā and the mana associated with that area does. This provides us with the opportunity to acknowledge that site and share its history with the people of Te Awa Kairangi.
We acknowledge Morris Love (Te Āti Awa, Taranaki, Ngāti Ruanui and Ngāti Tama iwi of Taranaki) for providing the cultural history about the project area.
Project Liaison
For queries relating to these works, please reach out to:
Robbie Woods - Kaiwhakahaere Matua (Project Manager), Te Wai Takamori o Te Awa Kairangi
M 021 256 6056
or email us at info@teawakairangi.co.nz