A portrait of Wellington’s
drought, 2015
We tried ringing both the local City and Regional council to get information on water flow rates in the Hutt River. After a day or so, the river ranger for the Hutt River rang us back. He was very helpful but indicated that the information was not as easy to find as before and that the Regional Council had set up a management company, Capacity to manage water treatment and supply, as distinct from the council which owns the and, the catchment and looks after biodiversity and environmental issues.
Successive councils have encouraged building development on the river plain and regraded the river solely as a hydrological matter, as a resource for supplying an increasing population with increasing amounts of water. Very little attention has been paid to conservation issues or even to ensuring the future of water supplies. This is illustrated by the article below, from 2011, which indicated proposals to reduce the minimum water flow to 400 litres/second.
To give an idea, during the crisis of 2013 the flow rates went right down to 1300 litres/sec and the photo illustrates what the Hutt River looked like mid-stream.
We were pointed towards the head of hydrology at the Greater Wellington Regional Council who very kindly provided the following comparitive information
Source: Greater Wellington Regional Council
What this indicates is the river flows at Kaitoke where water is extracted for water supply, on February 1 stood at 1215 litres/ second, which was 22% of the January average of 6710 litres/second.
The figures were similar further downstream.
Although river levels have not yet reached the low levels of 2013, it is unprecedented for river levels to be so low so early in the season (mid-summer).
Clearly there is a problem, especially if we look at the wider global situation.
However no one, at the official level anyhow, wants to see the bigger picture, or to acknowledge that there is a problem at all, although several people we have spoken to (as private individuals), acknowledge that this is an unusual situation.
I went back to the Council to ask for some comparative figures for the years 2013 and 2014
Looking at the figures, the flows for January in the upstream part of the Hutt River is at 1215 litres/second quite a bit less than what was measured for February (usually the drier month) in both 2013 and 2014.
What doesn't quite make sense is that the figure given for February, 2013 is 3849 litres/second in the very month when we had a water crisis. Something doesn't compute, but maybe that is just statistics for you.
It did confirm for me that last summer (2014) was also dry (2843 litres/second), so we can definitely say that the Wellington region has had three dry summers in a row with lower-than-average flows in the river. We are seeing a progressively drying pattern with the 2014 winter being warmer than usual (June set an all-time temperature record) and a very dry spring.
The following graph shows the flow rate for the river at midstream and reflects the one day of rain and a return to previous flow rates
The river at normal flow in late spring, November, 2014
This article from earlier in 2010 expressing concern at proposals to decrease the legal flow rates and the environmental effects of this on the river.
It looks as if these concerns are coming to pass.
Seemorerocks
The other day it rained for the first time in over a month. The next day the sun returned and today we have dry gales, so that any moisture will have gone in the matter of hours.
The weather has been uncharacteristically hot for for a normally-cool Wellington and sleep at night has often been elusive.
Just today there was this on Radio New Zealand
We have been getting steadily more alarmed at the dryness and lately by the low levels of the river which flows not far from out place.
There seemed to be no official response to what seems to us to be a potentially serious situation, especially combined with what we know about global weather patterns and about the onset of rapid climate change.
The other day it rained for the first time in over a month. The next day the sun returned and today we have dry gales, so that any moisture will have gone in the matter of hours.
The weather has been uncharacteristically hot for for a normally-cool Wellington and sleep at night has often been elusive.
Just today there was this on Radio New Zealand
January
was one for the record books with many of the main centres clocking
up high numbers of sunshine hours.
We have been getting steadily more alarmed at the dryness and lately by the low levels of the river which flows not far from out place.
There seemed to be no official response to what seems to us to be a potentially serious situation, especially combined with what we know about global weather patterns and about the onset of rapid climate change.
We decided to check the local response
It turns out there are some restrictions on watering gardens - every second day or by hand hose. On the other hand, on a walk with the dog we found that the street was being flooded by Water Services doing its monthly thing of cleaning the drains.
It turns out there are some restrictions on watering gardens - every second day or by hand hose. On the other hand, on a walk with the dog we found that the street was being flooded by Water Services doing its monthly thing of cleaning the drains.
We have gone to some lengths to have a water tank installed to catch and store rain water. However, I have been told that apparently people on the local council are against the idea because, quote, "people will just fill their tanks from the town supply" (while Water Services food the street on a regular basis - sic)
The whole country is in drought, in one form or another as shown by the following map
The Wellington area is set for a record of the driest January, receiving only about 3mm of rain in the month against an average of 70mm.
Looking at our own river levels going down has filled us with alarm, especially as this is happening so early in the season.
The North Island, and Wellington in particular, had its last crisis in February-March -April of 2013, when it got as serious as the region only having a few days water left before having to call on the storage lake.
This brought about some not-very-draconian water restrictions (although they did have 'water police' patrolling the streets to see if people were watering their gardens illegally. These restrictions were lifted very quickly when it began to look as if the crisis might be over.
The situation in 2013 was as follows:
"
The flow in the Hutt River is normally about 5000 litres a second at
this time of year, but that dropped to 1300 litres last week. ...The
regional council can take water from the river till it reaches a
minimum flow of 600 litres a second. But the emergency consent
reduces that minimum to 400 litres, providing up to 17 million extra
litres a day "
Our
response to this is reflected in the article, Wellington
water crisis: Drought risk driven by capitalism, below,
We tried ringing both the local City and Regional council to get information on water flow rates in the Hutt River. After a day or so, the river ranger for the Hutt River rang us back. He was very helpful but indicated that the information was not as easy to find as before and that the Regional Council had set up a management company, Capacity to manage water treatment and supply, as distinct from the council which owns the and, the catchment and looks after biodiversity and environmental issues.
Successive councils have encouraged building development on the river plain and regraded the river solely as a hydrological matter, as a resource for supplying an increasing population with increasing amounts of water. Very little attention has been paid to conservation issues or even to ensuring the future of water supplies. This is illustrated by the article below, from 2011, which indicated proposals to reduce the minimum water flow to 400 litres/second.
To give an idea, during the crisis of 2013 the flow rates went right down to 1300 litres/sec and the photo illustrates what the Hutt River looked like mid-stream.
This is how the midstream of the Hutt river looked in April, 2013
Site | Description | Average flow for Feb 1st 2015 (litres/second) | Average flow for January 2015 (litres/second) | Average flow for January 2013 (litres/second) | Longterm average flow for January (litres/second) | Average flow (litres/second) |
Hutt
River at Kaitoke (NIWA site)
|
Upstream
of water supply weir at Kaitoke
|
1215
|
1880
|
6710
|
5355
|
7771
|
Hutt
River at Birchville (NIWA site)
|
Mid-catchment
just upstream of Totara Park footbridge
|
3216
|
5129
|
20901
|
13761
|
22225
|
Hutt
River at Taita Gorge
|
Lowest
site in catchment. Opposite Manor Park golf course
|
3786
|
5838
|
24198
|
17116
|
23918
|
What this indicates is the river flows at Kaitoke where water is extracted for water supply, on February 1 stood at 1215 litres/ second, which was 22% of the January average of 6710 litres/second.
The figures were similar further downstream.
Although river levels have not yet reached the low levels of 2013, it is unprecedented for river levels to be so low so early in the season (mid-summer).
Clearly there is a problem, especially if we look at the wider global situation.
However no one, at the official level anyhow, wants to see the bigger picture, or to acknowledge that there is a problem at all, although several people we have spoken to (as private individuals), acknowledge that this is an unusual situation.
I went back to the Council to ask for some comparative figures for the years 2013 and 2014
Site | Description | Average flow for February 2013 (litres/second) | Average flow for February 2014 (litres/second) | Longterm average flow for February (litres/second) |
Hutt River at Kaitoke (NIWA site) | Upstream of water supply weir at Kaitoke |
3849
|
2832
|
4718
|
Hutt River at Birchville (NIWA site) | Mid-catchment just upstream of Totara Park footbridge |
11542
|
5740
|
11249
|
Hutt River at Taita Gorge | Lowest site in catchment. Opposite Manor Park golf course |
14473
|
6240
|
14049
|
What doesn't quite make sense is that the figure given for February, 2013 is 3849 litres/second in the very month when we had a water crisis. Something doesn't compute, but maybe that is just statistics for you.
It did confirm for me that last summer (2014) was also dry (2843 litres/second), so we can definitely say that the Wellington region has had three dry summers in a row with lower-than-average flows in the river. We are seeing a progressively drying pattern with the 2014 winter being warmer than usual (June set an all-time temperature record) and a very dry spring.
The following graph shows the flow rate for the river at midstream and reflects the one day of rain and a return to previous flow rates
The river at normal flow in late spring, November, 2014
This article from earlier in 2010 expressing concern at proposals to decrease the legal flow rates and the environmental effects of this on the river.
It looks as if these concerns are coming to pass.
Hutt
River lower flow bid comes under fire
The
Hutt River could be headed for more trouble with toxic algae and
deteriorated fish habitats in extremely dry summers.
2
November, 2010
Greater
Wellington Regional Council last week formally lodged its resource
consent bid to lower the minimum flow of the Hutt River for three
summers, apparently without peer review of its latest scientific
reports.
Hutt
City councillor Max Shierlaw, a scathing critic of the GWRC plan,
said the regional council has repeatedly claimed peer review support,
and its final application said initial feedback was relatively
positive and productive.
However,
GWRC general manager of utilities Murray Kennedy told Cr Shierlaw
that was wrong. The point of peer review was to get differing points
of view, and they were taken into account.
Cr
Shierlaw said Mr Kennedy gave the impression the Cawthron reviews
were favourable. "And now we know they're not."
Previous
peer reviews of GWRC's scientific research were critical of both
their methodology and conclusions, but GWRC said their concerns had
largely been met.
GWRC
said it needed to reduce the minimum river flow during construction
on the Kaitoke storage lakes, which had to be drained during work to
earthquake strengthen and increase capacity.
The
minimum flow would be reduced from 600 litres per second to 400 at
the Kaitoke weir. GWRC said it would not be taking more water
than currently allowed by its permit, just reducing the summer flow
to keep up with the need. It said the effect on the river would be
"less than minimal in almost all respects almost all of the
time".
That
claim is disputed by earlier peer reviews and possibly by a
scientific study of the trout fishery decline now being done.
Cr
Shierlaw has obtained the earlier peer reviews previously withheld by
GWRC, which show frustration with the regional council.
The
last of the peer reviews was done two years ago, and stakeholders
like Fish & Game said it had heard nothing since from GWRC. The
council says consultation with stakeholders continued after that and
all were heard and satisfied or objections noted.
Cr
Shierlaw said peer reviewers felt the council needed to do more to
address the pertinent questions with further, more detailed, studies
on the number of days minimum flow would occur.
One
reviewer, commenting in May, 2008 on the study of flushing flows and
algal growths, said he would not allow his name to be used if his
criticisms about methodology and conclusions were ignored. He also
said the study authors had been "unwilling" to take on
board his previous comments.
The
length of dry spells, and the number of freshes, or rainfalls lasting
more than two days that wash algae away, are more important than the
actual low flow, GWRC said.
However,
that is disputed by Fish & Game and the peer reviewers, who said
low flow can affect these things.
Toxic
algal mats in the Hutt River have resulted in the deaths of at least
five dogs which ingested some of the materials. The algae can also
irritate human skin.
The
2008 review appears to have morphed into the final application's
assessment of algal growth and potential aquatic impacts.
It
relies on last summer's river flows, which were never as low as any
previous low flow when problems occurred, as in 2007.
Cr
Shierlaw said it can not have been peer reviewed, or it would have
been included in those released to him.
The
final applications said it would be possible to conclude that the
proposed reduction in minimum flow at Kaitoke from 600L/s to 400L/s
will have a less than minor effect on algal growths in the river if
the predicted algal growths are similar to that under the existing
low flow conditions, and the existing flushing flow regime will be
maintained despite the reduced flow.
However,
the earlier peer reviewers, and Fish & Game doctoral researcher
Corina Jordan, who is working on a multi-year study of all factors
affecting trout, invertebrates and plant life in the river, said the
future cannot be predicted from limited historic data, and a wider
study is required.
Cr
Shierlaw said the length of low flows in dry weather is being
underestimated at about 15 days a year, when the earlier peer reviews
said there could be as many as 81 instances of low flows, with a
maximum number of 43 consecutive days.
Toxic
algal mats are said to become a problem after about 30 days of low
flow.
"They'd
likely be in the peak [water usage days] of summer. I can not imagine
what the effect of that would be. That's the kind of information that
requires further studies, according to the peer reviewers," Cr
Shierlaw said.
But
GWRC says the freshes will not be affected by the reduced flow
because water abstraction is halted during high flows as the river
above the Kaitoke weir is too cloudy to be properly cleared and
treated by the Te Marua water plant.
GWRC
said the low flow will not affect the river because of water from
other tributaries downstream from the weir. The only real problem
would be in a super dry year where there are long periods without any
rain and little water from the tributaries.
Cr
Shierlaw said they have not had that scientific evidence peer
reviewed. "Why not?"
The
earlier peer reviews say median flow is a better measure than low
flow, and more appropriate to maintaining the natural shape of a
river and its ecosystem, and the trend in the industry is towards use
of "environmental flows".
GWRC
said the reduction will mean about the same number of median flow
days as low flow days.
Cr
Shierlaw said Hutt City has asked [regional water retailer] Capacity
for its review of all this, particularly what is the proper flow
measurement, low-flow or median-flow.
"We
need to have suitable times when the flow must be increased. A
blanket low flow is not an acceptable position. There does have to be
flexibility."
He
said his colleague Margaret Cousins wanted a guarantee that if we
started to get algal blooms at a low flow of 400L/m the regional
council would put it back up to 600.
"Hutt
City Council will have to make a political decision to engage our own
work to review all of this, and report back to us whether they think
this stands up," Cr Shierlaw said.
.....
The
following article covers the crisis of 2013.
Greater Wellington Regional Council confirmed water use across the region reached 119 million litres, 11ML below the daily target of 130ML.
Water
usage hits lowest point since ban
Water
usage fell to its lowest point yesterday since water restrictions
came into place earlier this month.
29
March, 2013
Greater Wellington Regional Council confirmed water use across the region reached 119 million litres, 11ML below the daily target of 130ML.
If
water usage remained at or below the daily target, tapping into the
storage lake at Te Marua would not be required until mid-April.
Four
days of rain are forecast from next Thursday April 4, which would be
central to the council deciding whether water restrictions could be
eased back.
The
current ban on outdoor water use will likely not be lifted until the
region receives significant rain for a few days.
The
second lake at Te Marua was 100 per cent full and could be tapped if
necessary, but the council has requested residents to keep up water
saving initiatives while the dry weather continues.
Greater
Wellington said it is critical that for now, Wellingtonians keep up
their water conservation.
They
said the water situation was precarious but rivers had not fallen as
fast as predicted last week.
Water
supply marketing team leader Andrew Samuel said the storage lake at
Te Marua was full, at about 1900 million litres - about two weeks
supply - and ready to be used if needed.
However,
while river levels were much lower than normal, they were not as low
as forecasts had suggested, which meant the city supply could still
be drawn.
An
outdoor water ban in the city was enforced on March 16, and remains
in place.
Continued
focus on saving water has seen the city meet the 130 million litres
per day target set by GWRC for much of the last two weeks.
Greater
Wellington Regional Council Chair Fran Wilde says the public reaction
to the water situation has been great.
"It's
a huge result, although we're not out of the woods yet."
The
regions' mayors met for the greater Wellington mayoral forum in Upper
Hutt yesterday, and were briefed on the situation.
Chairman
and Upper Hutt Mayor Wayne Guppy said staff at all councils were in
contact with each other daily.
Water
savings during the drought had been ''outstanding'', he said.
''The
target's been set at 125 litres per person per day, and we're
effectively reaching the targets,'' he said.
In
the two days after rainfall on Sunday 17 and Monday 17 March, water
consumption went over the target but had fallen back as the drought
continued, he said.
Meanwhile,
Matiu/Somes Island in Wellington Harbour has re-opened, after being
closed from 12pm each day due to fire risk.
While
the fire risk was still high, the recent rain, the dropping air
temperatures and an increase in morning dew has allowed the island to
reopen, the Conservation Department said
.....
This is the only example that I have encountered in the Wellington media of a discussion of Wellington's water crisis
.....
This is the only example that I have encountered in the Wellington media of a discussion of Wellington's water crisis
Wellington
water crisis: Drought risk driven by capitalism
by
Ian Anderson
23
March, 2013
In
mid-March 2013, Wellington City Council announced a water crisis.
Nigel Wilson, chair of the region’s committee in charge of water
supply, stated that Wellington, Porirua and the Hutt Valley had only
20 days of water left. From March 16th, the city announced a ban on
outdoor water use by residents, with a $20,000 fine for violating –
commercial users faced no restrictions.
This
follows a regular pattern whereby the council focuses on curbing
residential water usage, whether through attempts at residential
metering or outright ban in this case. By implication, the council
blames residents for any water shortages.
“Non-commercial”
and domestic usage
The
council generally estimates “non-commercial” usage at around 350
litres per person per day, around half of usage overall. However,
“non-commercial” usage includes Council usage, theft, and leaks.
Leaks are unaccounted in bulk purchases; in fact around 20% of water
in Wellington is unaccounted, compared to a national average of about
10-15%.
Accurate
estimates for domestic consumption can be found not in the council
figures, but in the nationwide Quality of Life reports. Most
recently, the Quality of Life Report ’07 found Wellington domestic
consumption between 2001 and 2007 to be on average 170 litres per
person per day, on par with other cities. This is less than half of
the Wellington City Council’s estimates for “non-commercial”
use.
By
conflating various uses and misuses under “non-commercial,” this
manipulation of statistics gives the misleading impression that
residents consume the majority of water.
Climate
change and drought
The
North Island is suffering from its worst drought in 70 years. At the
time of writing Northland, Auckland, Waikato, Bay of Plenty and
Hawke's Bay are officially in drought, with more likely to follow.
In
an opinion piece for South Island paper The Press, Physical Geography
and Earth Sciences Professor James Renwick suggests that the risk of
drought in Aotearoa/NZ is on the rise. Renwick reports that rising
global temperatures, combined with lower soil moisture, could double
the risk of drought by the end of the century.
Although
Renwick does not explicitly state this, sticking strictly to his
geographical field, it’s well-established that greenhouse gas
emissions are driving global warming. The underlying causes of
increasing drought risk are not residential water use, or even
commercial water use, but global warming driven by capitalist
industry. Agriculture makes up the bulk of our emissions in
Aotearoa/NZ; in a grim irony, it’s also the sector most affected by
drought.
Solutions:
Socialism or barbarism
Discussion
of water conservation often focuses on showers, taps, toilets,
residential use. Wellington City Council has previously proposed
residential water meters, coupled with a user-pays system. User pays
for residential water has triggered community resistance in Auckland
and elsewhere, because it restricts access to water based on income.
Fightback opposes ‘conservation’ efforts which punish poor
families and residents.
Even
focusing solely on residential usage, a democratically planned
socialist approach could meet immediate needs and curb wastage.
Installing rainwater tanks can conserve up to 40% of potable water,
without significantly limiting real consumption. Fixing pipe leaks
could save up to 20% of usage. Investing in these options is not
profitable like user-pays, but would be more effective for
conservation.
There
are short-term options available for conserving water, both
residential and commercial. However, the underlying causes of
increasing drought risk are agricultural, industrial, economic.
Ultimately, to challenge ecologically destructive practices, we must
organise to take democratic control.
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