Saturday 10 May 2008

Is water frugality worth the effort?

There are many places on earth where water is a precious, finite resource. Sydney isn't one of them. Yes, Sydney recently had an extended drought - one of the worst in a hundred years - but our overall water storage never dropped below about 35%. Although this seemed very alarming at the time (the State government signed contracts to build a large desalination plant just before the last election, which is now being building but will probably never really be needed), it's actually a pretty good figure for the lowest point in storage. After all, if the low point was never less than say, 60%, you'd obviously have too much storage capacity.

Which brings up the obvious solution to Sydney's variable rainfall - more storage capacity. Our main dam (Warragamba) was originally planned in 1845, but construction was deferred until the severe 1934-42 drought got things moving. The dam was built in 1948-60, and it's capacity was actually reduced late last century when a new, lower spillway was constructed to guard against a "1-in-100-year" FLOOD!

Since Sydney has adequate, but highly variable, rainfall, there were plans for a second large dam to supply Sydney. Unfortunately the previous State Premier was a firm friend of the anti-dam green lobby, and declared part of the new dam site a national park in order to prevent a second dam being built.

So, we're stuck with an expensive desalination plant that will only be able to provide relatively small quantities of very expensive potable water during a severe drought. It also needs to be kept running the rest of the time (using expensive and environmentally unfriendly fossil-fuel generated power) in order to remain in working order. If we had a second dam of similar size to Warragamba our overall water storage would not have dropped below about 63% at it's low point, and we'd now be sitting at 80% of maximum capacity. A side benefit would have been some hydro-electric power generation to feed into the grid during times of high rainfall, when storage went above 90%.

Aside from the desalination plant, the government's main solution to solving Sydney's water problem during droughts is for consumers to "conserve" water. However, aside from the propaganda and peer-pressure value of small fines for "banned" water usage (eg. watering the garden on the wrong day of the week), there is actually little or no pricing signal used to encourage water conservation. For example, out last water bill was for average daily usage of 879 kL (down from 931 last quarter, and 934 the same time last year). However, out of the total $213.70, only $96.74 was "usage charge" - the remainder was for the general water service and sewerage service fees.

Therefore, in the past year we have reduced our water consumption by almost 6%, yet this would only reduce the bill by 2.7% (if water price and fees remain constant). The water bill was accompanied by a leaflet showing average daily water use targets for families of different sizes. For our household the target is around 750 kL/day. (They don't mention what the actual average figures are, or how an older house is expected to meet a target that is based on a modern house that uses all the latest water-efficiency devices!). If we somehow managed to reduce our water consumption by almost 15% to meet this target, our water bill would only go down by $14.66 (or less than 18c per day), or 6.9%! In reality, they are about to raise the water service pricing (to pay for the desalination plant!), so even if we cut our usage to the target figure we'll probably be paying more for our water bill this time next year.

Another example of government red-tape and ineffective incentives is the "incentive" offered to install rain water tanks for use as "grey water" (ie. flushing toilets, watering gardens etc.). Although quite large amounts are paid out by the government for installing a new rainwater tank, it's only available if you buy a brand new tank and get it installed by a licensed plumber. This means that you still end up with an "out of pocket" cost for installing a rainwater tank, and will take many years to recoup the cost through any water savings. Since the tank water can't be connected to the normal water reticulation system (as it isn't considered "potable" and isn't treated - some houses have dead birds, possums etc. on their roofs - yuk!), I can't see why a plumber is needed to stick a tank between your roof down pipe and the garden hose. I may install a small (preferably used) tank in our front garden to provide water for DS1's new vegetable garden, but it won't be eligible for the government subsidy.

Copyright Enough Wealth 2008

1 comment:

Anonymous said...

You might be interested to read a recent report by the Productivity Commission entitled 'Towards Urban Water Reform: A Discussion Paper" (available here).

Basically takes a look at the economics of urban water, where the subsidies end up, water trading and water rights principles, and some of the plans for the future (and how crazy they are).

If it doesn't make sense to do something on an individual level, there is a fair chance it doesn't make sense for society either!