The proposed Te Tai o Poutini Plan. Photo: LDR / Greymouth Star
The proposed Te Tai o Poutini Plan (TTPP) will immediately need to account for new modelling that shows the potential for greater coastal inundation for some West Coast towns and settlements.
Questions have also been raised about the implications of the current and planned flood protection schemes for Greymouth and Hokitika in light of the new coastal hazard information from Niwa, revealed a fortnight ago.
The plan committee last week received the new information commissioned by the West Coast Regional Council and agreed to start a process to notify a variation to the proposed combined district plan to accommodate the new hazard information.
The latest information, using a remote imaging method called Lidar, had not arrived before the proposed plan was publicly notified last July.
For Greymouth and Hokitika, and several coastal settlements not previously comprehensively modelled, the new information shows striking changes to the extent of coastal inundation, compared to the current hazard maps in the plan.
Updated Lidar modelling for the towns of Greymouth and Hokitika showing coastal inundation (in red) compared to the existing hazard overlays included within the Te Tai o Poutini Plan (blue lines). Photo: West Coast Regional Council / TTPP
Updated Lidar modelling for the towns of Greymouth and Hokitika showing coastal inundation (in red) compared to the existing hazard overlays included within the Te Tai o Poutini Plan (blue lines). Photo: West Coast Regional Council / TTPP
Principal planner Lois Easton said the new information "is quite a big deal" and showed significant changes from the existing maps.
A variation to the plan - which would have to be publicly notified for submissions - was needed to integrate the new information into the plan.
Replacing old plans
Once finally adopted, the TTPP will regulate land use and activity across the region. It replaces the Buller, Grey and Westland district plans.
Westland District Council chief executive Simon Bastion noted Hokitika was "severely impacted" by the changed modelling.
He wondered if the Hokitika river and sea protection works about to start had been accounted for in the latest modelling.
Easton replied: "These do not take into account the upgrade of the Hokitika River wall."
The plan currently did not have a specific Greymouth hazard map, although Westport and Hokitika did.
"In light of this work it might be prudent that the three main centres... need specific provision."
She said the new Lidar maps showed only "modelling and science work" and the planning implications had to be fleshed out in the plan.
TTPP project manager Rachel Vaughan said the new information did not replace detailed modelling already done in some specific locations, such as Westport.
Buller councillor Graeme Neylon asked if planners using the current district schemes had to give the new information weight when considering any building or subdivision consent, even before the TTPP was altered.
Easton confirmed that under the Building Act, council planners would have to give weight to the new hazard modelling as it was "the best available information".
Vaughan said planners were also required under the Resource Management Act to consider the new data for the likes of land use consents.
Buller Mayor Jamie Cleine said he supported a science-based approach where possible to inform the public.
"This is the latest information and obviously has big implications on current landholders but also future landholders and people thinking about investing."
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