Looking at local conditions

Report on the Hutt River - early December, 2015

Seemorerocks

In New Zealand we are just days into summer and although we have not yet had great heat, things are very dry. The river in its lower reaches near Lower Hutt is becoming extremely shallow with large quantities of shingle presumably washed down from upstream, and only a very narrow stream of water.

Yet just weeks ago the river was in flood, and just days ago there was a temporary spike in water flow.

We have had three years in a row with drought or near-drought during summer and with little or no recovery during the winter period, and it seems to me that the drying-out is cumulative.

While the temperatures have not been high this year, we have had a lot very strong drying winds from the north, and precipitation that does nothing more than moisten the surface. 

The soil is very dry.

 It is quite likely this situation will continue over the summer months. 

I am looking at the situation with increasing alarm as we move into an el-Nino summer fuelled by rapid climate change.

I shall be recording the situation as we move into the dryer, hotter period of the summer.

The photo below was taken a year earlier in October, 2014 and although it is slightly upstream from the other photos shows a more healthy river than today's photos.

The river in October, 2014 ----Sheila Merrigan

While there is good reason to be concerned about drought and a lack of water (a situation made worse by the fact that Wellington City also extracts water from the Hutt River) the Hutt City Council is drawing up plans to take out houses and trees from the western side of the river (the far side in the photo below) because of concerns of sea level rise and flooding in the next fifty years.

Looking across the river at trees that are slated to be removed to widen the course of the river opposite the Lower Hutt CBD.

Such a course of action, in view of the more immediate threat of drought and loss of water alternating with devastating flood events is, to put it mildly, wrong-headed and in my view has more to do with the views of engineers, as well as contractors and developers. Perfect economic stimulation. But it has very little to do with protecting the river and minimising damage.

Widening the course of the river and introducing more shingle into a river that is already becoming shallower over time will, in times of drought, reduce the flow of the river to, at most, a mere trickle.

Engineers, as we have seen on the farm where we keep our horses, have little if any understanding of the importance of stream bank vegetation and maintaining a meandering flow of water.  They like to widen and straighten the flow, thereby increasing the risk of damage from severe flooding.

This shows just how narrow the course of the river is in the downstream section

Here are the figures for the water flow at Taita Gorge showing a spike in flow a few days ago and a rapid drop-off in the flow rate.

Pam and I had a brief discussion on this, and a meeting of the newly formedHutt City Council environment advisory group. 

This is what the weather forecasters are predicting

Our windy, drizzly Wellington summer is here

El Nino's signature westerly and blustery gusts would be a frequent visitor to the capital over the summer, and would typically bring with them clouds, drizzle and rain. Average rainfall was expected in Wellington - though less moisture than normal might also be seen this summer, Mullan said.

"It's never the same day-to-day, you'll get glorious, quiet days and you'll get rubbish days. But you'll get more of the cloudy- and blustery-type days."

The following shows

The ocean temperature anomalies

Temperature anomalies in Australia and New Zealand