Current works

Removal/trimming of willows

11 January 2021

Tree trimming areaŌtukaikino Creek at The Groynes

  • When: Starting 18 January 2021 for about 4 weeks
  • What: Pedestrian walkway diversion

We’ll be trimming and removing some willows from the Ōtukaikino Creek between Groynes Park and Dickeys Road. The trees border the pedestrian walkway by the dog park at the Groynes. Many trees have dropped limbs into the creek bed, which are re-growing and restricting the flow capacity of the channel. Many are also in decline due to their age and need to be removed for the safety of park users.

Access to the walkway will continue. Pedestrians will be diverted around the work area, into the dog park and back on to the walkway from 18 January for about four weeks. Please follow all signs. In time, new plantings on the exposed banks will provide protection of the edge of the creek from high flows and help existing native plantings to flourish.

Thanks for your patience while we complete this routine maintenance work for your safety.

For additional information please call 0800 324 636 and ask for the Area Engineer – Northern.

Weed control in the Opihi River

December 2020

The Opihi River is one of the largest flood protection schemes in South Canterbury. Within the scheme Environment Canterbury staff and contractors carry out weed control measures in the open riverbed primarily to help flood flows pass through, and to enhance biodiversity values.

Environment Canterbury uses glyphosate-based herbicides to control weed growth in riverbeds and berms under the terms of Resource Consents CRC981580 and CRC041535. This is an important aspect of flood control. Left unchecked this vegetation is a flood risk, occupying the channel and forcing flood waters towards farmland and riverside communities. Weed growth can also contribute to the loss of aquatic habitats and nesting areas for native birds. Routine spraying can help avoid these effects.

Glyphosate is widely used in New Zealand and other countries as a general purpose herbicide, it is regulated in New Zealand by the NZ Environmental Protection Authority (EPA) and there are laws around its use. Products containing glyphosate are considered safe, provided users follow the safety instructions on the product labels. The EPA’s statement about glyphosate, as well as a fact sheet and information about how glyphosate is regulated in New Zealand is available here.

With the current weed control of the Opihi River by Pleasant Point, we are spraying the river bed fairway (onto the riverbed scrub, not into or near the water) to target lupin, willows and broom to alleviate congestion in the flood channel. The ability to maintain invasive weeds over large areas is critical for the ongoing maintenance of the river bed  for flood protection, biodiversity and natural character, including greatly increasing habitat for threatened braided river birds.

Kaiapoi flood protection | McIntoshs bend rock works

Works to reduce flood risk to the Kaiapoi township are planned from December 2020 to July 2021.

The Waimakariri and Kaiapoi River stopbanks are part of the Waimakariri-Eyre-Cust flood protection system. We will be strengthening the riverbank rock lining and placing stopbank rock armouring along the riverbank. We will also carry out improvements to the Ferry Road carpark, riverbank access tracks, and wetlands.

These upgrades will be carried out by Environment Canterbury, with funding support from the Ministry of Business Innovation and Employment’s Provincial Development Unit (PDU).

Find out more about Kaiapoi flood protection works at McIntoshs bend (PDF File, 368.46KB).

Lower Waitaki River erosion

On Friday, 31 July 2020 a public meeting was held at Waitaki Bridge Hall to discuss remediation works and gather community views on the proposed work and funding model. All Lower Waitaki River Rating District ratepayers were welcome.

We now need the help of ratepayers from the Lower Waitaki River Rating District to develop a solution that best represents the interests of all landowners in the Lower Waitaki area. Your rates notice will indicate if you are a ratepayer of this district.

Have your say on the Lower Waitaki River erosion

To get an idea of everyone’s views, we have designed a brief survey – the results will help us and Otago Regional Council understand what works should be done and help us decide how to fund them. This is your chance to have your say.

How to have your say:

The survey should take less than 15 minutes to complete.

Supporting documentation:


Environment Canterbury coordinates river engineering work in the Waitaki River downstream of the Waitaki dam on behalf of the Lower Waitaki Rating District (Canterbury and Otago ratepayers).

The objective of this work is to control unwanted vegetation growth in the central part of the riverbed and encourage vegetation growth on the on the river berms/margins.

This work limits the extent of erosion in the riverbed margins and adjacent productive land with the aim of protecting people and property from flooding.

Over the summer of 2019/2020 there were a series of heavy rainfall events in the Southern Alps that filled the lakes in the upper catchment and resulted in high flows in the lower river system.

  • These very high flow events, followed by subsequent continuous high flows in the river, have caused significant erosion at 13 different locations down the river.
  • To control the erosion at the 13 locations will require remediation work with an estimated cost of $1 million.
  • These costs are additional to the existing routine river control program costing approximately $500,000 which is currently financed through an existing funding model.
  • The proposal uses that same funding model to raise the extra $1 million required for a program of remediation at each of the 13 sites.
  • As yet, no decisions regarding remediation of the erosion have been made.

If you have any questions, contact customer services on 0800 324 636 ask for Shaun McCracken.