It has been wet!

I can't believe that it has been so long since I have written in this blog.  Largely that is because I've been writing in other places and on other topics, and that has felt like enough.  Now I'm standing for the Regional Council, it seems like a good time to use it again to post some thoughts that might tell readers something about where I'm coming from and the sort of Councillor I might be if I get in. 

It's Been Wet!

The news came on Tuesday that this July has been the wettest month on record.  By Tuesday afternoon, 212 mm had been recorded in Christchurch – more than three times the 61mm average for July.  As I write this on the 28^th July, it happens to be drizzling again, so the total might even go up a little! 

What is happening is exactly what was forecast a decade or two ago when scientists made predictions about how climate change would affect Christchurch; fewer large rain events and more droughts. Our flood infrastructure wasn’t built for these large events, however over recent years, a lot of flood retention ponds and wetlands have been put in in the upper reaches of the Ōpāwahō Heathcote River.  As the week comes to a close, those areas are holding back millions of cubic metres of water which will slowly be released into the river as the floods subside. Still more are planned and are needed.  

The upper reaches of the Avon have a lot more building already on them, so it is more difficult to put in water retention infrastructure like that in the Ōpāwahō catchment.  Luckily, though, perhaps, the Red Zone resulting from the Christchurch Earthquakes provides an area that can be flooded.  If we can plant it up with natives that can cope with flooding, we can also increase its capacity as a buffer against future floods.  We are still seeing issues further up that catchment around Edgeware, for example, that will need addressing in some way.

More can be done by council and residents alike. For example, using porous paving allows water to soak into the ground rather than run off quickly.  Likewise planting trees and wetland plants can also help slow down runoff and increase the city’s resilience to floods.

These issues are worth a lot of attention, because not only are we seeing bigger flood events, our low lying, flat city is likely to be strongly affected by rising sea levels – another symptom resulting from a warming planet. 

That is a topic for another post.