Following an early-morning Karakia on the site this week, works are set to begin to cover and contain exposed wood waste on the banks of the Orini Stream.
The Orini site, near the Keepa Road Bridge, is one of more than 30 known contaminated wood waste sites in the Whakatāne district. These sites are a legacy of the historic use of sawmill waste and other miscellaneous fill to reclaim low-lying land. Some of this waste is known to contain chemicals that may be harmful to human health after prolonged exposure. The key to ensuring that exposure is minimised at these sites is to maintain a capping or containment layer over the wood waste.
On the Orini site, the water flow in the river has scoured the bank out over time, exposing wood waste and fill along one of the banks. Works will commence soon to re-cover this area with clean fill and add a rock embankment to ensure that the river cannot erode the area again [rock armouring]. There will also be significant riparian planting, with natural vegetation following the earthworks, to enhance and help restore the area to a more natural state.
Whakatane District Council is responsible for the works, while the Bay of Plenty Regional Council, will oversee the project.
WDC Strategic Project Manager Jeff Farrell said the erosion issue had brought to the Council’s attention by a member of the public some time ago. “The erosion has become more obvious recently and we are getting the remedial works underway as quickly as possible, under emergency works provisions for consent processes. It has taken some time to get budget for the project, plan the rock works, consult with the different interested parties and arrange for contractors, but we now look forward to seeing the work completed within the next few weeks.”
BOPRC Works Engineer, Arch Delahunty, said the contractor will be getting works underway before the end of February.
“We expect that the first few days will be devoted to site set-up and ensuring all of the materials needed, such as rip rap, clay and silt, are available,” Mr Delahunty said.
“People might notice that the stream level is low while the works are carried out, as we will be keeping the floodgates closed for the duration of the project.”
Works on the site are expected to be completed by mid-March, with the wood waste area safely protected by layers of clay, geotextile cloth, top soil and rock armouring. A planting programme will be implemented in winter, once the site has stabilised, to create a more natural stream bank area.
- More detail on how clean fill (non-contaminated soil) covers wood waste sites and works to isolate the exposure pathways is on the website www.boprc.govt.nz/woodwaste
- All contractors are aware of the risks associated with working with contaminated materials and activity will be strictly controlled through the implementation of a Contaminated Site Management Plan.
- Image attached of design plan for completed works (Click on image to enlarge)