| 43 “They’re all being strengthened by increasing rock below the river level to protect them from being scoured out from underneath, and we’re also increasing the thickness of the riprap rock above river level.” T T Kim Newth Buying time for Franz Josef township Existing stopbanks have been raised and strengthened. As well, a new 850-metre link has been constructed to create a continuous protection line that now extends 2400m on that side. INFRASTRUCTURE West Coast Regional Council Franz Josef township, along with local farms, homes, businesses and infrastructure face mounting flood risks due to fast rising sediment build-up in the bed of the Waiho River, but stopbank raising and strengthening is buying some temporary protection for the local community. First-stage protection works on the river’s north bank, on the township side, were completed in June 2025. Most of the funding for this work came from a $9.2 million government grant, with the remainder paid for via a rating district contribution and local councils. Existing stopbanks have been raised and strengthened. As well, a new 850-metre link has been constructed to create a continuous protection line that now extends 2400m on that side. 5,000 tonnes of rock went into the stage 1 works, led by Greymouth-based MBD Contracting. The wider team working with the West Coast Regional Council (WCRC) on the flood protection scheme includes Inovo, Land River Sea Consulting, Tetra Tech Coffey and WSP. The Government is also co-funding flood-protection work on the Waiho River’s southern side with a $6m grant from the Regional Infrastructure Fund. The WCRC is putting in almost $4m for this next stage. Stopbanks on this side provide flood protection for a local aerodrome, SH6, farms and other local properties. Work has been steadily progressing. An unlined section of stopbank by an old district council rubbish dump is now freshly armoured with new rock, and a neighbouring section – already lined – is currently being repaired and strengthened. Further downriver is Milton’s stopbank that’s set to have the same treatment. “We’re about to go to tender for that work to repair and strengthen Milton’s stopbank,” says Tom Hopkins, WCRC capital programme manager. “They’re all being strengthened by increasing rock below the river level to protect them from being scoured out from underneath, and we’re also increasing the thickness of the riprap rock above river level.” One of the unfortunate by-products of stopbanks having been constructed in the first place is that the river’s natural alluvial fan has been restricted. It means sediment is now building up much faster in the existing bed than would otherwise have been the case. A 2023 report called Future Management of the Waiho River, commissioned by the WCRC, recommended a phased 10-year plan approach, with stopbank improvements buying time for land procurement, relocation of infrastructure and landfill sites in identified flood-hazard zone areas. The report recommended that the river ultimately be released to the south, to reduce critical risks to Franz Josef township, adjacent land and infrastructure. In 2023, a major new river channel developed into the Tatare Stream to the north, which poses mounting risks of its own to local oxidation ponds. “We have proposed to extend Havills Wall [adjacent to the oxidation ponds] by 400 metres in order to buy another two to three years,” says Tom. “This extension is subject to ongoing conversations between the community, the two councils and central government.” PH: 03 768 0218 DARREN: 021 310 453 EMAIL: ADMIN@MBDCONTRACTING.CO.NZ MBD CONTRACTING LTD - 50 ARNEY STREET, PO BOX 114, GREYMOUTH, 7840 MBD is proud to support West Coast Regional Council
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