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Water, water everywhere …

October 11th, 2010

… but we still can’t water the lawn. As I predicted more than a year ago, the gates have been opened at Wivenhoe Dam, and water saved at substantial cost last year is now flooding down the Brisbane River. Yet, anyone who wanted, for whatever crazy reason, to water their lawn today would be breaching Brisbane’s permanent water restrictions, which forbid watering on Mondays (why Monday? – I have no idea). And watering the lawn between 10 am and 4 pm is never allowed.

It makes sense to require water-efficient sprinklers, taps and so on – investment in such measures now will pay off in a drought. But, when water is plentiful, there should be no restrictions on when and how it is used. That way, restrictions will have more bite when they are actually needed.

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  1. Ikonoclast
    October 11th, 2010 at 08:43 | #1

    Overall, I agree but have a few minor quibble with the original post. Wivenhoe at 100% is at 100% of rated storage capacity not at 100% of flood mitigation capacity. I also made the mistake, in the past, of assuming that 100% rated storage capacity equals 100% flood mitigation capacity.

    Most large dams like Wivenhoe or Fairbairn can go to 150% to 200% capacity for flood mitigation purposes. Wivenhoe’s flood mitigation capacity runs to 200% (according to the media) and Fairbairn’s I believe runs to at least 150%. The 100% rating capacity is set at the spillway height or it may be set lower arbitrarily. When Fairbairn over-topped relatively recently there was about 3 to 4 metres overtop water height pouring over the spillway. This 3 to 4 metres of extra water is spread over the whole of the normal 100% dam capacity area plus much extra countryside. In layman’s terms, it is easy to see where an extra 50% is stored under these circumstances.

    Nevertheless, I agree that maintaining water restrictions above 80% (maybe not 60%) smacks of pointless bureaucratic power being wielded for nothing better than little tin god reasons.

  2. Ikonoclast
    October 11th, 2010 at 08:47 | #2

    If I may post again. These tin gods are usually smarter than I give them credit for. I wonder if this stance relates to continuing the mindset that water is (always and everywhere) scarce so that a scarcity premium can remain attached to the cost. It smacks of corporate managerial thinking.

  3. wilful
    October 11th, 2010 at 10:52 | #3

    I just think there should be a proper price on water, scarcity based. There shouldn’t be restrictions. Maybe a limited quota system, the first 100l. a day are almost free.

    If there are genuine hardship issues, these can easily be addressed through transfers elsewhere. If there are “equity” issues (i.e. rich people have green gardens), well that’s a market economy in action. Rich people have nicer cars and houses too.

    Of course, in two months I’ll be on 100% rainwater so it’s all my problem whether I have enough storage and infrastructure. I wont have to pay for a desal plant though.

  4. Sam
    October 11th, 2010 at 11:17 | #4

    Agreed. Also, WIN tv reports on Toowoomba’s still dire water situation. Apparently there is a pipeline from Wivenhoe to Toowoomba’s dams, and some small amount of water is being pumped there to augment supplies. Unfortunately the QLD Water Commission is refusing to provide the water for free to council (not counting electricity pumping costs which are always borne by Toowoomba), and so the pumping rate is well below what it could be.

    They won’t let Toowoomba have Wivenhoe’s water for free even though they are just dumping it over the spillway! This is crazy!

  5. Jon Brodie
    October 11th, 2010 at 11:42 | #5

    Meanwhile in north Qld and specifically Townsville we have no water shortages of any kind, we are connected to Burdekin Falls Dam ( the most reliable dam in Qld) which is already over the spillway in October before the wet season, Ross and Paluma Dams are full, we could support a population of 1 million for water easily (not suggesting this mind you) and yet we still suffer under weird water restrictions and pricing models developed for SE Qld on the assumption that all of Qld is the same as the SE. The really sad part is that in Townsville we have a range of environmental issues but for some reason water availabilty is seen to be the most important and the real issues ignored.

  6. wilful
    October 11th, 2010 at 11:51 | #6

    we still suffer under weird water restrictions and pricing models developed for SE Qld on the assumption that all of Qld is the same as the SE.

    That is bloody odd. In Vic restrictions are by Water Authority. IIRC there are 24 of them, so 24 separate assessments.

  7. peterm
    October 11th, 2010 at 12:49 | #7

    Wifful restrictions on a per Water Authority basis make sense. When you consider water restriction you need to consider the plant capacity as well as the price of the raw materials. The water processing plant that includes treatment plants, mains and reservoirs has a finite capacity that is a local issue. I suspect it is easier for a water authority to restrict use rather than upgrade the plant if the output potable water is essentially free.

    There is also the issue peak (when the mains are fully utilised) verses non-peak usage. This may result in some of the time of day based restrictions. Although why restrictions are the heaviest on Monday in Brisbane when all the reservoirs should be fully changed after the weekend is a mystery. I would have thought a Mid-Week restricted day to allow all the reservoir to catch up would have made more sense.

    Is a market based approach better than all these mysterious regulations?

  8. Donald Oats
    October 11th, 2010 at 13:15 | #8

    The more I read about this the less I know :-(

    Meanwhile in the Murray Bridge land of plenty, we have had minor lifting of water restrictions for residential gardens and the like. In Murray Bridge though, it is common for the older houses and even many of the new ones to have some serious tank storage. The rainfall here is determined in large part by what makes it over the Adelaide Hills and Mount Lofty, so we are in the 33cm per annum range when lucky.

    The thing about the whole Murray-Darling basin thing is that these days an almost microscopic model of current needs (however defined) and current flows should be feasible. From that it is possible to run a seriously large number of scenarios to determine impacts of allowing these needs to be i) met; and, ii) for various extra draws to be permitted, say for the many irrigators along the M-D system. Without such a model of the physical system and the human/agricultural/environmental components, I fail to see how the M-D system can be i) managed; and more specifically, ii) account for multi-year scenarios, including the effects upon humans of several back-to-back good rainfall years or eased restrictions; and indeed, if iii) the physical system is too constrained to meet the minimum needs of the existing uses, let alone some larger load upon it.

    Okay, so it is in the multi-objective realm of optimisation and requires accounting for many soft constraints (aside from the obvious things such as state variables like rainfall, eg ground-reaching precipitation per unit time, eg hour or day), and upon the stochastic nature of many state variables. Never-the-less, it is useful to have a model as a starting point for determining policy.

    When it comes to what might euphemistically be referred to as homeland security, the natural assets as well as physical infrastructure – electricity grid, communication networks, etc – are all part of the risk assessment and analysis. We have adequate information to have maps of important infrastructure, so it is reasonable to think that a similar system model is feasible for the M-D system. I wonder how many detailed models are out there, and whether they do indeed provide more informative “outcomes” than mile-high, course-grained models (of which there are probably many)? Does anyone reading this work on such stuff at the sort of detail I’m talking about (Pr Q excepted, since he started the blog-thread on this)? It would be great to have some comments by such people…

  9. spangled drongo
    October 11th, 2010 at 14:14 | #9

    “But, when water is plentiful, there should be no restrictions on when and how it is used. That way, restrictions will have more bite when they are actually needed.”

    John, couldn’t agree more! But you see, we must be DISCIPLINED.

    Children no, but adults…..

  10. Greg
    October 11th, 2010 at 16:47 | #10

    “But, when water is plentiful, there should be no restrictions on when and how it is used. That way, restrictions will have more bite when they are actually needed.”

    I’m surprised to hear an economist say this. Expectations of uncertainty will cause investment to be delayed, won’t they? The risk premium?

    From an ecological point of view, freshes are needed to rejuevenate river systems. The social value of healthier ecosystems may be greater than that of watered lawns in a climate that can’t really support them.

  11. spangled drongo
    October 11th, 2010 at 20:10 | #11

    Greg, from that same ecological POV SEQ Water could store another 50% [3/4 full] and still have time to release the excess if flooding looked likely.
    That way lawns could be watered, an even better flush could be provided and our expensive and CO2 emitting desal plant could possibly be left to Rust In Peace.

  12. Ronald Brak
    October 12th, 2010 at 10:41 | #12

    Heavy rain tends to result in lots of gunk ending up in dam water and this puts an extra load on water treatment, so having water restrictions while a dam is overflowing is fairly common. But I have no idea if this is a factor for Wivenhoe at the moment, and I don’t know if it was an issue beforehand.

  13. Fran Barlow
    October 12th, 2010 at 11:00 | #13

    Personally, I’d like water to be charged by the litre with a reasonable threshhold for normal household usage. Once you exceeded that, you’d be on marginal rates.

    I’d like meters in residences to be more user-friendly and to warn you when over any 3-day period you were using water at a rate that if continued, would take you over your threshhold. Perhaps it could even identify where water was being used so if you had a leaking tap, you’d know and could attend to it.

  14. jquiggin
    October 12th, 2010 at 16:12 | #14

    I don’t think freshes are a big issue for the Brisbane River. It’s tidal for a fair way upstream from the mouth, and flowed pretty steadily even through the drought, when no water was being released from dams.

  15. Robert Merkel
    October 12th, 2010 at 16:28 | #15

    John,

    My guess is that – aside from bureaucratic inertia – a lot of people actually like the restrictions as it makes them feel like they are doing something for the environment. Kinda like bringing your own shopping bags to the supermarket, when they burn twenty times as much oil driving their car there.

    It’s the Victory Garden of the 21st century.

  16. Craig Henderson
    October 12th, 2010 at 20:15 | #16

    John,

    I might have missed a nuance in your @14 comment, but I would offer the following.

    Water is always always being released from Wivenhoe to supply Brisbane’s drinking water. It flows down the mid-Brisbane to the Mt Crosby Weir and treatment plant. As an aside, there’s an hypothesis that this is an environmental issue of water levels in the Mid-Brisbane that are ‘too’ constant. Even during drought. May just be an hypothesis looking for a home :) .

    Below the Mt Crosby Weir the river is tidal, but still fresh to slightly brackish, depending on tide levels and fresh river flows past the weir. There are also bull sharks at Colleges Crossing (not far below the weir), but that’s another story.

    My understanding is that there are certainly increased levels of water treatment required during flood times – partly due to water/sediment inputs from some of the creeks that feed in below the Wivenhoe Dam wall, but also from the stirring up of the sediments in the mid-Brisbane river bed as flood flows wash through.

  17. sdfc
    October 12th, 2010 at 21:10 | #17

    I don’t think you necessary want restrictions to just bite but to change behaviours.
    Behaviours like having a water guzzling lawn in an inappropriate environment.

  18. enohpi
    October 16th, 2010 at 00:56 | #18

    I can’t see why we should ever need water restrictions in this country. It’s not like it’s a scarce resource. This is Australia not the middle east. We get more water than we can poke a stick at, we simply don’t have the storage capacity.

    300,000 odd new immigrants each year – all consuming approximately same amount of available water. Capacity must keep pace with population increase.

    Yes some animals will lose their habitats boohoo, it’s called progress.

  19. derrida derider
    October 19th, 2010 at 10:18 | #19

    I don’t think you necessary want restrictions to just bite but to change behaviours.
    Behaviours like having a water guzzling lawn in an inappropriate environment.

    – sdfc@17

    Why? If there’s plenty of water this year, there’s plenty of water. So why is changing behaviour an end in itself? This is the sort of “green puritanism” that gets my goat – consumption is seen as inherently evil rather than as carrying pragmatic and generally manageable problems. If I want a lawn for my kids to play on, and am willing to pay the full price, who the hell are you to pass a law saying I can’t?

    As I’ve said elsewhere, swingeing but temporary drought levies are a far more efficient and sensible way of managing water consumption when the dams are low than municipal water police and dobbing neighbours. When it costs $50 a pop to water a big lawn properly only those who really, really want or need it will water it. When there’s plenty of water it can be supplied at marginal cost and everyone can be happy with no harm done.

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