Designing for Climate Change II

In the first post I wrote about stabilising the stream banks and feeding out pollarded willows to the goats. I also mentioned the casuarina and cabbage trees planted in the riparian corridor. Here is an image of them.

Screen Shot 2018-05-03 at 1.16.59 pm

Much of this work designing for climate change came after the 2015 Whanganui floods. Here is a picture of the neighbours place the day after.

Screen Shot 2018-05-03 at 1.28.33 pm

This is the neighbour on the other side. Lots of dead sheep.

Screen Shot 2018-04-30 at 3.59.40 pm

But truth be told we had started our work before the June flood. As a matter of fact, just two days before the storm hit the Whanganui region I was finishing up a French drain around our home with the help of my daughter.

Screen Shot 2018-05-03 at 1.36.44 pm

Because it was mid-June we were also preparing our garlic for planting later that night.

Screen Shot 2018-05-03 at 1.37.08 pm

At least someone enjoyed the weather.

Screen Shot 2018-05-03 at 1.37.29 pm

Our calf, Heidi, weathered the storm down in the valley. Note the culvert that I am clearing in the image below and keep it in mind when viewing the image that follows.

Screen Shot 2018-05-03 at 1.38.17 pm

The willow in the foreground gives you the relative location of the culvert, which you can’t even see due to the extensive plantings along the stream following fencing off the riparian corridor.

Screen Shot 2018-05-03 at 1.15.47 pm

But this post should really be about the hillsides, where slips occur, and how to reduce the risks of future slipping. We have planted over 100 3-metre poplar poles that come from the regional government. They should be soaked for a week before planting 700 mm deep in mid-winter.

Screen Shot 2018-05-03 at 1.33.37 pm

We locate them mostly in the valleys where water is concentrated during storms.

Screen Shot 2018-05-03 at 1.17.34 pm

After three winters of planting, we are now up to the upper slopes. On the side of the farm with the goats we use tree guards and on the side with the kune kune pigs we do not use them.

Screen Shot 2018-05-03 at 1.17.57 pm

But I am told that it takes seven years for the roots of poplars to grow broad enough to hold the hillsides against slips, which raises the question: what to do during the intermediate years to prevent slips from taking out the poplars? Our answer has been targeted drainage.

Screen Shot 2018-05-03 at 1.18.20 pm

There are certain areas where we can capture concentrated surface runoff on the hillsides and leapfrog it over the most vulnerable slopes. This is not ideal, but may be a reality in a world of increasing extreme weather events.

Screen Shot 2018-05-03 at 1.18.33 pm

In summer we take the pipes down and store them under trees out of direct sunlight. This preserves the plastic pipes and retains water high on the landscape during the dry season. It is an expensive measure but part of what I call Triage Permaculture. Seasonally installing and dis-installing the pipes is part of what I call four-dimensional design management.

Screen Shot 2018-05-03 at 1.29.45 pm

Sadly, we’ve also had a neighbour dumping water onto our land illegally, which has caused an additional slip.

Screen Shot 2018-05-03 at 1.29.31 pm

Because they will not take responsibility for their own water as prescribed under The Building Act, I have had to put in a drain and a sump (made from a flower pot) and more plastic pipe to redirect the water away from the vulnerable area.

Screen Shot 2018-05-03 at 1.29.14 pm

We’ve also put in a surface drain to draw stormwater away from the top of the slip, which is dangerously close to a fence and a major farm track.

Screen Shot 2018-05-03 at 1.18.48 pm

This has all been a massive effort requiring tens of thousands of dollars and hundreds of hours labour. But at the end of the day, if I want my children to inherit a resilient farm there really is no other option.

 

Peace, Estwing