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We and many or the residents of Pinehaven and Silverstream oppose a large residential development on the hills above them because it will greatly increase flooding and landslides. The Councils' flawed flood model will allow development on the hills to go ahead without proper stormwater management. This will result in large volumes of extra stormwater runoff to inundate Pinehaven and Silverstream.

Greater Wellington Regional Council and Upper Hutt City Council say they have put 'hydraulic neutrality' rules in place to make sure development on the hills doesn't make existing flooding any worse. But the Councils' inflated base model will mask extra runoff from the development and hydraulic neutrality will not happen. Residents have much strong evidence that shows the Councils' base flood model is grossly inflated. 

The flaw shows up in modelling by Council's consultants which incorrectly finds that the impact of future development on flooding will be only minor when in fact it will be major. But the Councils have used a false flood mapping audit to cover up the truth about their future development modelling and the faulty base model. 

The following summaries explain a key piece of evidence, the Councils' 'future case scenario', which clearly shows that their base model is seriously flawed. There is lots of other evidence that shows the Councils' base model is flawed, but the flaw shows up most clearly in the Councils' 'future case scenario'. 
The Councils have managed to avoid talking about the 'future case scenario' for 7 years, but the truth about their flawed base model has finally surfaced. These summaries explain what the Councils have done and how it seriously endangers Pinehaven and Silverstream with bigger landslides and more widespread and frequent flooding if the Councils base flood model is not fixed.

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