I hear a lot of complaints about Water Bills . . . . . but Town Water is one of the ‘Great Bargains’ of our age!
Don’t Believe Me?
Well lets look at the facts.
Typical Water Charges
Well I live in Melbourne’s City West Water area so my water charges are:
Water Service Charge
$54.65/quarter. This is to cover things like the maintenance of the thousands of km’s of pipes that are ready to deliver the water to you.
Water Usage Charge
To encourage people to be responsible in the water usage the cost/kilolitre rises at 440 litres per day and again at 880 litres per day. (The average Melbournian uses 160 litres per day, but my wife and I are careful and only use around 100 litres each per day)
$2.3060 per kilolitre for the first 440 litres of water used per day.
$2.7241 per kilolitre for water usage above 440 and up to 880 litres per day.
$4.0749 per kilolitre for water usage above 880 litres per day.
Cost For A Family
Well the daily cost for an average family of 4 using 640 litres per day is:
1st 440 litres $1.01
2nd 200 litres $0.54
Service Charge $0.60
Total $2.15 /day (Equivalent to $3.36/kilolitre)
Remember this is for a product that has been; Collected, Stored(for up to 4 years), Treated, and Delivered to your tap exactly when you want it.
You may not be familiar with what a kilolitre really means but here are 3 equivalents.
It weighs one tonne.
It is equivalent to a cube 1m x 1m x 1m.
Just over 4 large wheelie bins.
2,000 x 500ml bottles
Comparison With Any Other Product
If you can find any other product that you can have delivered to your door for $3.36/ tonne let me know . . . even dirt costs around $60/tonne.
Comparison with Bottled Water
Well the cheapest I could find bottled water was in my local Costco, where it worked out at $500/kilolitre!
Comparison with Beer
One days water supply = the cost of 1 stubby.
Still think Town Water is expensive? . . . . Then leave a comment!
There has been a lot of talk in the Melbourne papers recently about ‘Slab Heave’ when Building on Clay so I thought I would explain how to minimise the risk during construction.
A key issue when building on clay is to avoid any extra moisture getting into the clay under the slab. causing the clay to swell, by keeping the area around the slab well drained.
This is particularly important where part of the slab is below the natural ground level such as when ‘Cut and Fill’ is required to get a level site.
Detail For Protection Against Soil Heave
The diagram below shows what you should be looking for, during construction, to protect the ground under your slab from gaining moisture.
The key issues are:
The excavated surface falls away from the edge of the slab for at least 1m with a minimum drop of 75mm.
Where the water will not continue to flow away from the slab an Aggi Drain in a granular back filled trench should be provided. This drain should be a minimum of 100mm below the surface level of the clay and fall to a suitable discharge point.
Any trench in the area between the slab and the aggi drain should be topped with well compacted clay to ensure there is no easy passage for water to penetrate under the slab.
Roof drainage should be connected to a suitable point of discharge as soon as possible after the roofing material is fixed. (See Temporary Downspout)
Although the requirement for an aggi drain is not as critical where the ground slopes away from the slab, it is nevertheless good practice to have one.
If you want to redevelop or subdivide an existing urban house block, you might find that a planning condition is that you will need to provide On-site Stormwater Detention (OSD).
You may also find it is a condition on individual blocks on smaller subdivisions.
Why Is Onsite Stormwater Detention Needed?
Before development of towns and cities a large proportion of the rain that fell in an area soaked into the ground or flowed slowly across the land to a creek or river. When areas started to be developed two things happened:
More and more of the land was built on, or paved, which meant rain was unable to soak into this ground.
Stormwater drains were built to carry the rainwater quickly away from the houses to be discharged into streams and creeks.
Initially while Australia had a small population this didn’t cause too many problems.
Since the mid 1950’s and the rapid growth in population more and more land has been built on.
The result has been more and more water has been discharged surface water drainage systems causing overloading of the piped systems and flooding of the rivers.
In order to try and reduce flooding Planning Authorities are attempting to reduce rainwater flows from developments to a flows similar to an undeveloped site.
OSD On Large Subdivisions
If you buy a block on a large subdivision it is unlikely that you will be asked to provide OSD on your Block. This is because large developers as a condition of the overall development have to provide Stormwater Detention Storage for the whole development.
The way they usually do this is by making much of the open space they also have to provide as Ponds, Lakes or Wetlands, which can fill up during periods of rain and then slowly empty. (Now you know why so many developments have a reference to Water in their name)
This diagram indicates a charged drainage system. These are sometimes called either a “wet” or a “pressure” system.
With this type of system a section of the pipe always remains full unlike a Conventional System.
As the pipes are under pressure it is essential all the joints in above ground and underground pipework are fully watertight
A neater appearance than having pipes above ground.
Allows you to discharge water at a height above the ground level at the down pipe.
It is more likely to block as the flow through the pipes can be fairly slow and the low points can collect silt. Silt will get deposited at flow rates below 0.6m/sec which will be the situation for most rainfall events.
It is also more difficult to unblock.
Can cost more with excavation and additional inspection fittings .
Potential for mosquito breeding in water unless appropriate screes are installed.
The vast majority of new houses will have a conventional (sometimes called a Gravity, or Open system) storm water drainage system discharging to either:
Public Surface Water Drain – Typically in Eastern States
Soakwells on Sandy Sites – Mainly in WA
With a conventional system like this the pipes are either vertical or at a slope towards the discharge point.
A feature of this system is that when there is no flow all the pipes are empty.
Simple and inexpensive to design and construct.
If well designed, and constructed, the speed of flow in the pipes will prevents silting and subsequent blockage.
This type of system can look very untidy when taking water to a Rainwater Tank that is some way from many of the downspouts (It results in lengths of pipes suspended in mid air)
Difficult to transfer water to a discharge point that is above the ground level of the building, although below the gutter level. A problem often encountered on demolition and rebuild projects and battleaxe blocks.
If you are planning a rainwater tank or are having problems with getting storm water to a suitable discharge point you could consider a Closed System