Tank versus Dam

Local dams might be the answer to tanks.

Local dams also offer lots of lower risks than big central dams and other benefits neither the big dam or a local tank can offer.

Lets explore the three –


Deploying tanks in every home is a great way to truly localise water supplies, particularly in suburban areas that have good roof catchment areas. So they definitely add value but are they the best solution for all situations, I’d say unfortunately tanks are not a 100% solution because –

  • rain falls unevenly across suburbs (some have too much that goes to waste in overflow and some have not enough)
  • water consumption is uneven across households
  • roof area (rain water catchment areas) by household vary according to many factors including type of dwelling e.g. high rise apartments (also called ‘flats’ in some countries)
  • the cost of plumbing overflow from millions of small household tanks back into a central collection point is prohibitive in time and money and disruption and in many low lying suburbs simple gravity means further negative impact on the environment with pumps.
  • tanks have a cost to the environment in construction and installation that must be multiplied by millions of households so there is a material cost but it is not as obvious as the cost of more centralised solutions

So something in between household tanks and big monolithic centralised city (MCC) dams (like Sydney’s Warragamba dam) might be better.

Big Dams

Of course big MCC dams are centralised and get economies of scale in many ways but they have their issues too –

  • Algae bloom (like Sydney is experiencing right now) means there is a concentration risk – if something happens to the one dam, millions of people suffer
  • Terrorism targets are worse – e.g. poisoning supply with MCC dams for the same reason of concentration risk although admittedly the security can be done better because they are usually more remote (surrounded by native bush/forest catchment areas) and centralisation enables more cost effective security
  • They are usually distant from the communities they serve – costs of pumping, routing are higher.
  • May be located according to rain fall that varies over time (such as when housing growth reduces natural green areas and this impacts rainfall) and there is another concentration risk there too – this one is particularly difficult to control.

Local Dams

So the local dam idea has some merit, imagine one in the nature reserve near you if it has a gully or valley –

  • Natural valleys are proven collection points, less expensive land acquisition and clearing.
  • They are often already clear with nature reserves, parks etc around them becaus ehte land is harder to build on and local councils have them declared as parks or nature reserves
  • Downstream usually has no issues with dwellings because it is already a stream or river and the outflow/overflow is less than an MCC by orders of magnitude.
  • There is still a degree of centralisation so the cost of pumping back into ‘the system’ is more sensibly shared across thousands of households (better than tanks) and is much lower capacity (and hence cost) than a full MCC style pumping station.
  • It adds the the local wild life’s ability to be sustained in good and bad times, same for flora.
  • Significantly reduced concentration risk because if the supply is compromised, assuming a city has 20 or thirty smaller dams the loss of one or two through algae bloom or poisoning or pumping station failure is still tiny relative to the total available.

My colleague Marc Lehmann also has some good points on this and prompted me to finally write down some of this stuff. I’ll do another post on this with more detail and the relationship with storm water harvesting some time too.

Cheers, Peter.

Equal Pay – Why Is It No longer On The Agenda?

I threw my hat in the ring this week to be candidate for my area for a major party in the upcoming elections.

We don’t know the date yet but it is fair to expect the PM to set one soon and late November is in frame.

So, apart from brushing up on the constitution and related documents on the web I started asking friends and family what were the issues that concerned them.

My sister, always on the money for her demographic suggested that equality of pay is still an issue and arguably more of an issue than ever.

Why? I thought equality has been legislated and discrimination is punished legally and socially.

Well, on consideration there is a little depth to this assertion. For example the average marrying age has moved back. Maybe because less are getting married at all – sure. But same goes for when people have their first child, it is getting much later.

So the old adage of women leaving the workforce to have children drives lower wages is failing even more than it did originally, particularly in the last 5-10 years with up to 10 years being added to ‘first half’ careers – ie the time before women stop to have their first child.

A wide range of other aspects are also increasing this perspective.

Women are increasingly deciding not to ever have children due to a combination of person choice (or their partner’s) and also to a significant but lesser extent infertility on their or their partners behalf.

It is also widely accepted to be gay now too although this clearly no long seems to preclude the adoption of children or having their own through scientifically assisted means. Frankly while a trendy topic I think the numbers involved here wrt gays having children would have minimal impact on this particular debate.

Personally, I suspect the average gay female wage would be closer to the average male wage for just about every industry and geographic area. This is a topic in itself for separate debate I might do another blog on so lets not divert our attention for now and remain focused on at least 50% of the entire population for now.

Of course we can not ignore the recent bump representing not a child but a rise in the number of children being born – while good it is still a short term trend so the assertion holds that women are time wise capable of and typically are actually working in paid employment much more relative to say 10 years ago.

So is this concern about equal pay valid? If people think it is an issue then of course it is one and it is valid but I’d like to see more structured and facts applied to the debate.

I particularly think we need to explore two avenues –

– research on the perception from women (working or not) mainly but also from men and separately from employers to see it this really is a political issue people care about

– research on the facts – commercial industry surveys and independent collation of hard salary and full package benefits by gender, industry and location to see if this equality is material

With that ammunition, the decision is then to decide is this an issue worth opening up to wider political debate because –

– it may or not be ‘winnable’ – i.e. what can be gained politically from reiterating an existing issue (I try not to shy away from issues on that feeble premise – winnable or not a debate usually enlightens all).

– it may not be ‘fixable’ – I reiterate we already have the non-discrimination legislation – do we now need cultural change supported by industry or government (a tough one really)

I am sure this is a topic of interest to women and also to most men for a wide variety of reasons but just how much do we care, and what can we do or what should we try to do?

I suspect it comes second to freedom of speech, having a roof over your head and food to eat and clothes on your back, probably even clean air to breath and water to drink. But after that it will be interesting to really see where it fits in our collective priorities – particularly if the pay gap is small and shrinking (albeit probably not fast enough).

I’d like to open it up for comment.

Cheers, Peter.

Sydney august 17, 2007.

Postscript: Didn’t end up being the candidate for my electorate. A nice local guy by the name of Jim got the job (but I did make the short list of two) I wish him well.

Parental Persistence

In the computing world, persistence means writing information to media so it is kept more or less permanently. Persistence generally is recognised as an admirable attribute like commitment or dedication.

In this modern world with so many ways of staying in touch instantly here and now, it is easy to forget the importance of long term perspective across generations – from people that have been around a long time before us.

Parental persistence is the process of capturing and sharing memories from your elders, parents, grand parents, anyone with memories from before you were born. It might seem like the meanderings of old and irrelevant, out of date people but you will be amazed at the relevance these thoughts have across generations for your children, grand children and their grand children.

Here is a list of suggested questions to ask your elders, sit them down comfortably in a familiar place with a video camera on a tripod zoomed up so you get their facial expressions as they relive their experiences. Make sure you have lots of film and time.

Maybe you will get a wonderfully successful result on the first day, or maybe you will have to try twenty times over a couple of years and still only get ten minutes of joy. The next generations will treasure your efforts regardless.

‘Think of this camera as representing all the generations that follow you. This is your chance to talk to them, perhaps in 5 years, or 10 or 100. Things you have seen will be impossible for them to imagine, things they will see are impossible for us to imagne.

We can’t stop time, but we can attempt to bridge it with this video.

As we progress, tell the next generations anything you want to share. As we go through your life tell us what went well and what didn’t, what you learned, your likes and dislikes, who and what you loved and what you would change or never change. This story is your story, take as much or as little time as you like. Take as many side roads or diversions and tell as many tales as you like. That is what this is all about.

Lets start by finding out about –
– your name, age, where you are from and how you would describe yourself
– your parents and their parents
– your siblings and cousins
– your friends
– the rest of your family (partner, children, grand children, step children, others)
– your schools
– your childhood memories
– your other educational experience/s
– your work experiences
– your sports and hobbies
– your fondest memories
– your loves – people and experiences
– food you like or remember
– best holidays
– worst holidays
– favourite places
– toughest times
– biggest successes
– what innovations do you think amazed your parents
– what innovations have amazed your in your life

We now know a lot of about you, some wonderful times and tough times. If you feel comfortable, can we also talk about some personal moments –
– your health and health habits as a child, young adult and now
– meeting your partner, getting married
– arrrival of children
– life changes around getting married and/or having children
– losses in life of loved ones
– things you love about their children and grandchildren
– what inspires you
– what fears do you hold
– your scariest day
– your most courageous day
– what or who has given you the most guidance in life
– what hopes you hold for your children and theirs
– advice you would offer the world in coming decades
– advice you would offer your ancestors

Make lots of copies of the video, as interviewee to sign and date them. It costs a bit but resist the temptation to make one copy as a backup and keep both. Think of 5 or 10 or more peers (siblings, cousins and close friends particularly) in your generation, make a copy for each of them and then make another few spares. Encourage them to do the same in return with their elders.

If you are generous and you and/or yor peers have children just make a copy for each of them. They and their children will thank you for it long after you are gone.

Notice that these are all open questions, you don’t want yes or no answers and it is important to allow people latitude to discuss what is important to them.

If you follow these simple suggestions, your efforts will be shared with future generations and you too may be remembered this way when you become an elder of our society.

God bless and a long and joyous life.

Cheers, Peter.

PS: Print this suggestion list in the darkest inkk you can and include copies with the video.

PPS: Forward this link to your brothers, sisters, cousins and friends now then ring your parents or other elders and book a time for their Parental Persistence.

Peter J Cooper
Sydney, Australia
6 June 2006.