'Basic premises' in hazard lines report backed

A Victoria University professor has come out in support of the contentious hazard lines affecting 1800 properties on the Kapiti Coast.

Associate professor James Renwick believes the basic premises in Roger Shand's report, on which the hazard lines are based, "stand up very well with what is understood about climate change and coastal erosion".

There was a public outcry in August 2012 when Kapiti Coast District Council announced predicted 50 and 100-year shorelines based on Dr Shand's report and placed them on property owners' Lim reports.

The council last year appointed four experts to review Dr Shand's report.

The panel published its draft report last week, recommending the hazard lines were not robust enough to remain in the proposed District Plan, concluding that Dr Shand's coastal risk analysis, and work carried out earlier by John Lumsden, was of high quality but needed modification and updating.

Dr Renwick, of Victoria's geography, environment and earth sciences department, said he understood owners' opposition, but there was no question that sea levels were rising. "The Shand report was fine scientifically, it had all the right ideas about risk of inundation . . .

"Sea levels are rising. It is quite startling how quickly risk can change with a modest amount of sea level rise.

"The hazard lines look perfectly fine, but I could not say whether they exactly accounted for the beachfront topography of every property."

Coastal Ratepayers United, representing aggrieved property owners, wants the lines removed immediately from the council's website, but the council plans to wait for the panel's draft report to be completed and analysed.

Capital Economics director and former government policy adviser Bryce Wilkinson said the panel's proposal that the Shand report could be modified and updated with minor changes to be fit for purpose was "baffling".

"It did not model accretion [beach buildup] or sediment balance and was not shown to be probable."

Public policies should demonstrate likelihoods backed by evidence, Dr Wilkinson said, not "fanciful projections".

"It is absurd to expect coastal scientists to be able to predict out to 2050 and 2100 with any degree of reliability or accuracy."

The Dominion Post