Kaikorai Stream’s flood potential needs considering

IT is difficult to comment intelligently on the report (ODT, 5.7.18) about the diversion of wastewater into the Kaikorai Stream during floods.

To do so comprehensively, one would need to have information about the additional volume of water involved.

However, it is of concern that the report implies that the only negative consequence of such a strategy is instream pollution.

It is probably not widely known that during the 2015 floods, a small number of Green Island businesses and dwellings suffered significant flood damage and there is an extensive history of road closures in the area due to flooding.

Because a large area of its catchment is covered by impervious surfaces, the stream can rise very quickly and this makes it vulnerable to short duration, highintensity downpours when it is already swollen by steady rain.

Perhaps a greater concern is the fact that the stream invariably carries large logs and other debris when swollen.

This kind of blockage in one of its many narrow channels could cause much more significant flooding problems.

I accept that decisions should be made on the basis of the greatest good for the greatest number.

But I also think that full account needs to be taken of all the potential consequences. Bryan Horne

Green Island

Great use of plastic

CONGRATULATIONS to Polybuild and the Waitaki Resource Recovery Park in their plan to recycle plastic into building materials (ODT, 7.7.18).

With our planet becoming awash with plastic and, on the local scene, landfills becoming clogged up, this is a winwin that should be applauded by all. All strength to their arm in obtaining government funding; this project ticks so many boxes.

I trust that the relevant regional and national authorities will see the benefit, and ensure that no redtape hinders progress, and that any encouragement and support that can be provided by them, will be.

R. Gardner

Waverley