Asit Biswas, an expert in international water resource management, has changed his mind. He no longer believes a world water crisis is a crisis of physical supply. It is, instead, a crisis of management. He also does not believe wars will be fought over water. What gives? Have a listen.
I’ve been mulling over this for a while. I’ve been looking for regions similar to New Zealand in terms of climate and geology, or to regions within New Zealand, but different in how the society manages its water. How do other people solve the same water resource problems, or fail to solve as the case may be? Call it comparative water resources management.
My training is a mix of ecological engineering, physical geography and ecology, with a dash of anthropology, environmental planning, and a side order of reality and current affairs. I see a landscape first as a geological-climatic template, around which the hydrological-ecological system is folded. Into this I add humanity. There are feedbacks up the hierarchical chain, but a first pass is a good start.
So to compare water resource management practices I need to isolate the non-human variables first – the environment. You can never do this perfectly, except perhaps in a lab. But we only have one lab – the Earth – and I’m not going to play dice.
If I look for a region similar to Canterbury – an environmental isomer or doppelganger – I start with the biophysical environment. The plains are one big depositional system, geologically. Layers of gravel and finer sediment have been laid down over millennia forming a big aquifer-sandwich. Most of the water comes from snow and rain that fall in the Alps, while the plains is itself on the sub-humid side. Both surface and subsurface waters are important, and ecosystems are certainly water-dependent, albeit really only moderately.
Turning to the human system, it is a developed liberal democracy with a GDP heavily dominated by agriculture – dryland grazing, dairying and broad-acre crops mainly. Outdoor recreational activities include tramping/hiking, kayaking, fishing, boating. Key fishes of interest are trout and salmon – even though they’re introduced. Population is mainly urban, and rural agriculture is far from subsistence.
Does this sound like California? It does to me.
If California is a suitable doppelganger for Canterbury then, will California’s current problems and solutions apply here in the future? And can Cantabrians learn from the successes and failures of our trans-Pacific neighbours?
A few days before the Save the Elephant research site was washed away by a flash flood, villages along on the western flank of Mt Elgon were hit by landslides, killing at least 100.
Minister David Wakikona, MP for Manjiya County in Bududa district, said
“Everybody is dead. 320 people are unaccounted for. I don’t know if we shall get any survivors out.”
The trigger was also heavy rain associated with the onset of the March-May rainy season. And while landslides are always to be expected sooner or later on steep terrain, this area had became more susceptible since the 1960s due to land clearance for crops and fuel.
I visited the area in 2008. The local Uganda Red Cross team gave me a tour of the mountain side and I met the elders of one of the villages above Mbale. Both the Red Cross and the villagers were concerned about landslides and rock falls that had claimed several lives. And the village elder seemed at least vaguely clued up about the cause: deforestation. That said, Oxfam released a report in August 2008 about the potential impacts of climate change on Uganda, and suggested climate change would increase the danger of landslides. While that may be true, I think it is rather useless – the important factors around Mt Elgon at least is deforestation and village vulnerability.
Mountain hillslope and village site above Mbale, eastern Uganda.
Trees reduce the tendency for soil-mantled slopes to fail in three ways, though not all are relevant at any one site or time. The most obvious is that their deeper and stronger roots bind the soil together vertically and laterally; they may also bind the soil to underlying bedrock if shallow enough. The heavier trees increase the friction of any failure surface within the soil. And the higher transpiration of the trees can dry up the soils more, thus requiring more water-logging for slope failure to occur. Trees are also helpful in limiting the run-out distance of rock falls by serving as a natural debris belt.
With this in mind, the main recommendation I gave to the Red Cross and villagers was to plant fruit trees. They are so below the poverty line that they need both nutritional or economic assistance as well as protection from landslides. Fruit trees hits two birds with one stone. It reduces their vulnerability and increases their resilience to the next natural hazard.
Fruition Sciences, based in the US and France, has won the top prize in Imagine H2O’s competition “to help innovators and entrepreneurs turn great ideas into real-world solutions that ensure available clean water and sanitation.” Fruition showed particular business potential by making significant water savings for nine California grape growers.
“Fruition co-founder Sebastien Payen said he saw a real challenge in the wine industry because there were “absolutely no plant-based sensors to optimize water management.”
He combined his expertise in sensor and information technology with co-founder Thibaut Scholasch’s research on vine water status to create the Web application.”
The system seems to work as follows.
Sap flow sensors at the base of the vines monitor how much water is flowing through the plants, and hence how much is transpiring. Weather data and knowledge of the site are used to estimate the evaporative demand at any particular time. This is the rate the soil and plants would lose water by evapotranspiration if they had all the water they could use. These data are sent off for analysis by “proprietary algorithms”, to compute how much irrigation should be applied, and when, in order to optimise fruit composition.
The water saving most probably comes from irrigating only if it would increase transpiration. Above a certain level of soil moisture, called the stress point, transpiration levels out. At this point, more water won’t mean more transpiration, but would mean more evaporation. And if you go even higher, to the soil’s field capacity, you’d start losing water below the roots from gravity drainage. For the plants, evaporation and drainage are a waste of water.
The proprietary algorithms no doubt estimate the actual transpiration rate of the plants and the potential rate imposed by the microclimate, and then assess whether the plant is stressed, how stressed, and whether it should be irrigated.
Sap flow sensors are are a step up from measuring soil moisture status alone, which is also monitored to guide irrigation applications, but is further removed from what is actually going on in the plant and hence typically less informative.
Idiot/Savant, commenting on the threat posed to Christchurch’s drinking water from agriculture, wrote today:
“Basically, its us or the cows. That’s the stark choice we are looking at. And put like that, there can be only one answer: the cows have to go, or be regulated to within an inch of their lives to prevent them from being a threat to ours.”
I don’t know if this is theatrical hyperbole or literal forecast. Dairy farming certainly poses current and future threats to water supplies and waterways, and as such would need to be managed, but I don’t see an either/or dichotomy. I drink milk – both cow and soy – though more out of habit than any nutritional requirement since calcium can be readily obtained from non-diary sources. I eat cheese – typically the snootier varieties – and my quality of life would definitely drop if I had to sustain a cheese drought. I also drink Christchurch water, untreated, from the Canterbury Plains aquifers.
What seemed to spur I/S to this remark is the observation that we are “increasingly drinking cowpiss”. Artistic licence this time, I’m sure. It comes via coverage of Russell Norman’s visit to eutrophic Lake Ellesmere, and the quote therein:
“A GNS scientist said last year a 200-metre deep well in Avonhead had shown a “statistically significant trend” in increasing nitrate-nitrogen concentrations since 1995.”
The GNS scientist in question is Paul White. His comments came from evidence he gave last year regarding the Central Plains irrigation scheme [PDF]:
“A 200.2 m deep National Groundwater Monitoring Programme well located near Avonhead has recorded a statistically significant trend (with a rate of increase of 0.006 mg/L/yr) in nitrate-nitrogen concentrations since the NGMP began sampling the well in 1995. This rate of increase is low, but the increase indicates the potential of intensifying land use to impact on Christchurch groundwater quality. Groundwater quality in the 200.2 m deep well is good; median nitrate-nitrogen concentration is 0,24 mg/L, and the median oxygen concentration is 6.3 mg/L, of samples taken since 1995.”
This trend does not pose a health risk, but could very well be an indicator of the reach of agricultural pollution.
In any case, it is the pollution that is the problem, not the cows. More intense dairying would likely lead to worse water quality all else being equal, but there is no need to assume all else will be equal. In conjunction with regional planning to limit the extent of dairying, there is room for on-farm management practices to improve. The question is both how many cows and how to manage them.
I’ve had an affinity with art since before I can remember. I went through a Seurat phase in primary school. Chalked up an asphalt car park with Picasso’s Guernica. And explained numerical modelling for my PhD defense with Colin McCahon.
Art and science both seek to offer narratives about the world. Science takes the objective path, or close to it, while art meanders along the more subjective. But they often overlap or complement each other, as was the case at COCA last Saturday.
The exhibition was by Artists for Save Our Water, an ensemble of 12 artists gathered essentially to protest against a reservoir and irrigation scheme that had been proposed for central Canterbury. I covered Saturday’s closing reception previously. (The Press was there, but they didn’t seem to be taking notes.)
After the reception, I took the opportunity to talk to a couple of the artists about their work.
Margaret Ryley is an artist and potter based in North Canterbury. While Artists for Save our Water is in its second year, she has been depicting water in her pieces for much longer. Her initial inspiration was the Ashley.
“I grew up playing in the river, observing the river, feeling the stones.”
But over time, Ryley has noticed things change. Both along the Ashley and the larger Waimakariri just north of Christchurch.
“The Waimakariri was this large river that you went over going into Christchurch. And in earlier years I can remember it flooding. I can remember my father having to go up round the gorge to get into Christchurch because then there was a huge volume of water. It’s not been the same since…”
It is this new, quieter river that Ryley conveys through her artwork. Pieces of pottery and porcelain lie scattered along an arc, the small white porcelain pieces framing the larger glazed clays, fitting materials for a river. There was no definite boundary, and in fact the pieces had been moved slightly by observers, much the same way that real rivers are.
The white porcelain pieces are the white stones of the river. Their occasional black lines represent both bridge and geological past. Of the clay pieces, the walnut ash glaze gives a golden colour, the copper a blue to mimic the water. But there isn’t much blue.
Ryley says of the rivers:
“There are more and more piles of stones and less and less water.”
Her concern is that a natural and beautiful ecosystem is being degraded by careless use. Nesting birds are deprived of suitable nesting sites. Charismatic braids lost. These are risks posed by greater abstraction of water.
As part of the Save Our Water project, the 12 artists toured the Waimakariri River, and the site of the proposed reservoir. I asked Ryley what new insights she garnered from this experience.
The first was the sense of how fleeting anything you do to the rocks was. They could become your canvas, but before too long the river would wash the canvas away.
“But also the magnitude of what people were trying to do to make use of the water which they see as being wasted going out to sea without any regard for the natural order of things. And to look at the area that they wish to dam, to have only the hilltops which would be islands in the middle of a dam, and a great dam that overshadowed the township of Coalgate. It’s just horrifying that people could think that they could do that.”
The second artist I spoke with was painter Linda James. She has not always focused on rivers…
“But I have actually always done water; something about the power of the water.”
James is fascinated by the constancy and patterns of water flow, its circularity, its eddies. These features come across strongly in her three large paintings, each of a waterfall. Not of the Waimakarari, but made out as picturesque postcards.
I noticed the unconventional canvases: free-hanging, unframed and comprising a patchwork of smaller canvas pieces.
“I like the way it makes a texture and you get separate patterns going. Like you’ll get the big picture and then you’ll get the patterns of the surface.”
In one corner of one painting she has written the words ‘Out of the chaos’.
“There’s always these patterns that are formed in whatever you look at. … There’s somehow these patterns are always there but it’s so destructive. I mean if these rivers are in flood … Harmony can be so ruthless.”
Of the bigger picture of water use in Canterbury, James agrees that we should be growing crops and irrigating them, but not on such a large scale.
“It lacks any foresight.”
Canterbury’s water management needs a serious overhaul, according to artists and activists who gathered for an art exhibition at Christchurch’s COCA on Saturday.
The exhibition featured works by 12 artists brought together by local artists Sally Hope and Jane Zusters for the second annual Artists for Save Our Water project. The focus this year was on the Waimakariri River, and the proposed Central Plains Water scheme.
The artwork chosen as the banner of the exhibition was a work by Ramonda Te Maiharoa. Her composite image depicted a river being blocked by a line of wooden-framed glass doors. In their centre was a door handle and key-hole. The message was simple: With the right key, the CPW’s reservoir in the Waianiwaniwa Valley need not be built. And indeed, ultimately, it was not.
In attendance were advocates and politicians of a range of stripes, but all in agreement on the need to improve water management.
Murray Rodgers, Chairman of the Water Rights Trust and author of ‘Canterbury’s Wicked Water’, spoke about the need to shift water management in Canterbury to balance economic and environmental needs. He emphasised the need to think long-term, and to replace “undisciplined growth” with “sustainable growth“.
Rodgers was highly critical of successive governments, both Labour and National, for their bureaucratic hold-up and inaction on freshwater management, despite many good reports produced by MfE.
Rodgers further decried the degrading waterways, unfit to swim in, and lays blame on unsustainable agricultural practices:
“Cows are still shitting in some Canterbury waterways. Lowland streams run dry. Behaviours that cause the on-going rise in nitrate levels in ground and surface waters are expanding, those behaviours are not contracting.“
Rodgers’ leadership on water issues was subsequently praised by Dr Russel Norman, co-leader of the Green Party. Norman went on to stress that it was the NGOs and volunteers that are ultimately moving the discussion forward.
According to Norman, these events surrounding local water management and agricultural intensification are small snapshots of a bigger pictures. In the long run, he said…
“It’s about what kind of relationship do we want to have to the planet, and to our own local environment, and hence it’s about what kind of people do we want to be.“
Brendan Burns, MP for Christchurch Central and Labour spokesperson for water issues, acknowledged Murray Rodgers’ speech, saying that “almost all of what he said was absolutely, bang-on correct,” and conceded Labour’s past actions have not been entirely to the benefit of sustainable water management.
Burns also called Canterbury’s track record on water management “woeful,” and cited a recent Ecan report claiming that 1 in 5 farmers had been in serious breach of resource management consents, but he balanced this by saying that he has yet to meet any farmer who actually wants to damage the environment.
Both Brendan Burns and his National Party counterpart, Nicky Wagner, echoed Russel Norman’s sentiment that the issue of water management was about who we are. Wagner specifically recognized the work of artist Nigel Brown, and his piece ‘Water Through the Fingers’.
Changing the tone after the politicians, or at least changing the vocabulary, was artist and author of ‘The Water Thieves’, Sam Mahon. Mahon provided a geological and birds-eye view of the Canterbury Plains, woven over millennia by the braided Waimakariri River and her sisters. To Mahon, water mismanagement risks putting the “eternal weaver” to sleep.
While much of Saturday’s event was taken up by speech, it was the artists’ visual and textural works that provided the speech’s context. After the event I had the opportunity to talk to two artists about their works, why they were attracted to the water issue, and what they sought to convey. I will share their words with you soon.
Reuters has a video documenting the eviction of occupants of the Mau Forest in south-west Kenya. Again in the coverage, the journalist cites water supply concerns as a driving force behind the evictions. I don’t buy it.
Nick Smith has suggested to farmers that they start offsetting their greenhouse gas emissions by planting trees. A risk with this is that planting trees may compromise water supply.
Compared with pasture, trees tend to reduce the amount of rainfall that reaches rivers and aquifers. A larger canopy traps more rain as it falls, so it evaporates directly from the leaves before even seeing the soil. Deeper rooted trees are also able to tap deeper soil water and groundwater stores, supplying more water for plant transpiration. On the other hand, a row of shelter trees slows the drying of pastures during strong, warm winds, such as during Canterbury nor’westers.
If there is ample water to begin with, the effect may be inconsequential. If the region already experiences seasonal water shortages, planting trees may be a risky proposition.
A rule of thumb I use to delineate at-risk regions is a threshold of 600-700 mm of annual rainfall. Any less, and planting forests where they were not previously may translate to drier streams and lower water tables. These numbers are rough, and would need more attention for any given region, but the message is simple.
The effect on water supply would increase with the area of forest planted. So would the amount of carbon sequestered. This leads to a trade-off between carbon sequestration and water supply. Farmers should consider carefully where they plant their trees so as not too compromise their irrigation needs.
The NYT has a tragic story about a hunter-gatherer group in Kenya that may lose its ancestral forest home.
The Kenyan government is gearing up to evict tens of thousands of settlers, illegal or not, from the Mau Forest, the Ogiek’s ancestral home and a critical water source for this entire country. The question is: Will the few thousand remaining Ogiek be given a reprieve or given the boot?
My question is: Will this eviction actually improve the water resource situation?
I have serious doubts.
The NYT continues:
No doubt the Mau Forest is crucial. It is — or more accurately, used to be — a thick, staggeringly beautiful forest in western Kenya, capturing the rains and the mist and, in turn, feeding more than a dozen lakes and rivers across the region, even contributing to the flow of the Nile.
But in the past 15 years, because of ill-planned settlement schemes (the government essentially handed out chunks of forest to cronies), 25 percent of the trees have been wiped out. Much of the forest is now simply meadow. The Ogiek say there are fewer antelope and bees. They constantly use the Kiswahili word “haribika,” which means spoiled. Scientists say the environmental destruction has led to flash floods, micro-climate change, soil erosion and dried up lakes.
There is a lot of mythology wrapped up in forests. For over a century we – many scientists and non-scientists alike – have believed that trees are good for water resources. That trees make rain. I even ran into this impression while in Uganda last year, near the Kenyan border. Unfortunately, in most circumstances, it is the opposite that is true: forests reduce the quantity of available water compared with other land cover types.
On the one hand, it’s nice to see your pet research interest getting air time in the NYT. On the other hand, it may be being misunderstood or misused by the Kenyan government to the detriment of a large group of people.
I have asked the reporter about the scientific backdrop to his article (while also suggesting that it my not be as cut-and-dry as he was led to believe), and will root around myself for the low-down.
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