2023-04-11 - April 2023 update
Despite a wet start to the year, we’ve been making good progress on finalising Stage 2. We’ve included details in this update, what’s planned for Stage 3 and when this work is expected to be underway. We’ve provided an update on what’s happening with the inanga (whitebait) ponds near Stages 1 and 2.
Please don’t dump rubbish and greenwaste on or near stopbanks
Illegally dumped rubbish and greenwaste is expensive to remove and can cause damage to gear our contracting teams use to maintain stopbanks – tree branches and mowers don’t mix.
Stage 2 almost complete
This stage is divided into two parts, A and B. Stage 2 involves 20 properties, from 48 Henderson Street to 80 Landing Road and 2 – 6 Mananui Avenue. Due to consistently bad weather, Stage 2A progressed more slowly than expected, however it’s now complete, with repairs to the stopbank done and some finishing touches being made to grass cover and fencing.
Stage 2B involves work to the section of the stopbank where the floodwall is also located. Two teams have been working, with one removing vegetation and the other focusing on repairs to the stopbank. The teams are working with Whakatāne District Council to reduce the cumulative impact for residents beside the Hinemoa Stream, where a stormwater upgrade project is planned. We appreciate the ongoing support of residents and the positive feedback – thank you!
Stages 3 and 4 involve the stopbank behind Riverside Drive and this work is scheduled for the 2023/24 and 2024/25 constructions seasons (spring, summer and early autumn).
Why aren’t some trees allowed in certain areas on or near a stopbank?
Tree roots can grow through a stopbank and leave holes allowing water (seepage) to flow through it and cause the stopbank to fail. Tree roots can also get underneath floodwalls, lifting wall sections and breaking joints.
Stumps can also cause problems as they rot, leaving holes in the ground and potentially allowing water from sand layers beneath the ground to come up around the stump and impact the integrity of the stopbank.
Here are some photos from Stage 2 highlighting the risk of some trees and tree roots close to the stopbank and floodwall.
Members of the team checking out soil characteristics following removal of a large puriri tree.
Tree roots impacting the base of the floodwall and top of the stopbank.
Whakatāne Project Future Proof: What is it?
You may have heard that further upgrades to flood defences in the Whakatāne area are planned: Whakatāne Project Future Proof. This project will happen over multiple stages and involves upgrading the stopbanks and floodwalls along the town centre stretches of the river (from McAllister St Pump Station through to the Whakatāne Boat Ramp).
In April 2017, the Whakatāne district experienced widespread damage to homes, property, businesses, as a result of the events generated by ex-Tropical Cyclone Debbie. As the climate changes, communities across New Zealand are adapting to meet the challenges of a rising sea level and more frequent, more significant rain events that may cause flooding.
Using data gathered from historical events, as well as what we understand about the changing climate, we know town flood defences need to be upgraded. We have been working closely with the Whakatāne District Council and Te Rūnanga o Ngāti Awa and will be having conversations with the community in the future, to keep you informed about work that is planned.
Bylaw Authority records
The team has had some queries about prior Bylaw Authorities issued for work on a property that may not have been passed on as part of information when the property has been sold.
Any property owner in a Bylaw applicable area can contact the Regional Council to find out if a Bylaw Authority has been issued for the property previously. Council has records for all Authorities that have been issued since the original Flood Property and Drainage Bylaws came into effect in 2002.
It’s worth noting that the Safeguarding our Stopbanks work is being undertaken on public land to remove structures and plantings that present a risk to the stopbanks integrity. This work is being undertaken under a project specific issued Bylaw management plan.
The bylaws aren’t in place to stop people from doing any work on their land, but instead ensure any work carried out doesn’t inadvertently affect the integrity of Council’s flood protection assets.
Helping safeguard native fish species
Where and when it’s practical the Council team tries to include habitat restoration as part of river and drainage maintenance work. The inanga ponds at Ferry Road are a good example of this. Inanga are the most common native fish species caught as whitebait.
The other species that make up the whitebait catch are banded kokopu, giant kokopu, kōaro and shortjaw kokopu.
The work in the Henderson Street area requires fill material to strengthen and repair the stopbanks. Excavation of the inanga ponds along the river edge is a very cost-effective source of fill material which also avoids the need to ‘truck in’ fill through residential streets in close proximity to schools.
The ponds provide important refuge for native fish species that are otherwise vulnerable to predatory fish in the main river channel.
Ongoing planting of native plants around the ponds is being supported by Halo Whakatāne and Trees for Survival, who are working with local schools to assist students to grow native plant seedlings and learn about native fish life cycles and conservation values.