The Hutt River is a steep alluvial river that starts from the Tararua Ranges and enters Wellington Harbour at Petone. It flows through the mountainous terrain of southern Tararua and western Remutaka Ranges with several streams and rivers from the Eastern and Western Hutt hills joining with it on the journey.
The catchment is spread over 655 square kilometres, nearly seven times the area of Wellington Harbour. The 56-kilometre long Hutt River has a history of flooding with four main tributaries – Akatarawa, Mangaroa, Pakuratahi and Whakatiki. A storm in any part of the catchment could result in flooding. It takes only seven hours for heavy rain at the top of the catchment to turn into floodwaters at the Hutt River mouth.
Flooding impacts more people, more often than any other natural hazard. With around 200,000 people living alongside the river, this work is one of the key tools we use in flood protection management, minimising the risks of flooding to lives, homes and businesses.
Over the past 15-20 years the rock structures along the river have moved and collapsed, making the riverbanks more vulnerable to erosion and flooding. We need to keep them well maintained so that we have a resilient and protective barrier. We expect to see more flooding events as climate change brings more severe weather.
We are using heavy machinery in order to improve our defences, which may include activities such as: diverting the water channel while we work to ensure fish passage and sediment disruption is minimised, create additional rock structures to build up our banks and move existing rock structures to create stronger banks.
We will be working at 29 sites along the river and we have site specific event management plans, which in same cases including relocating fish while we are working. The sites along the river will be monitored both before and after the work takes place, to ensure sediment disruption is minimised.
Remedial work won’t be carried out on weekends and public holidays and the Hutt River Trail will remain open. Some diversions around worksites may be in place, so please follow signage and instruction from the work crews.
The Hutt River provides opportunities for many environmental, ecological and social benefits, ranging from weekend leisure activities to ecological links down the whole valley length.
Following a review of the 2001 Hutt River Environmental Strategy, a new and revised Action Plan has been developed. Te Awa Kairangi/Hutt River Environmental Strategy Action Plan (HRES Action Plan) frames the vision and sets out what is needed to achieve the aims and objectives identified by the community for the management and enhancement of the river corridor environment.
Greater Wellington works with our regions communities to manage the flood risk from rivers in our catchments. Our approach to managing flood risk is to understand river and floodplain processes and provide a coordinated response through our floodplain management plans in partnership with the community.
Hutt Floodplain Management Brochure [1.2MB] (PDF 1.2 MB) [this is designed to be printed at A3 size]
The Greater Wellington Regional Council (GWRC) Hutt River (Te Awa Kairangi) flood protection project for the City Centre section is a combination of stopbank raising and widening on both banks of the river, as well as river channel widening. The project stretches some 3 kilometres from Kennedy Good Bridge to the Ewen Bridge downstream and completes an upgrade to the level of protection for the more intensively urbanised river plain contiguous with the Hutt City town centre.
This project’s urban interface also gives rise to opportunities for additional ‘layers’ of public benefit to be realised over and above flood protection. These additional benefits can be gained from combining the projects of stakeholders, particularly Hutt City Council’s (HCC) town centre improvements called Making Places, and the New Zealand Transport Agency’s (NZTA) Melling Bridge and highway intersection improvements, with the flood protection project.
The map below shows an overview of the Hutt Valley. To find out flood hazard information about a specific area, download the plan number shown below from the flood map box on the right of this page.
Alternatively you can view our GIS maps online.
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