Downloads

Should we drink Recycled Effluent, or can we do something cheaper & More sustainable with it?

Grey/Black Water reuse is a viable option, but it's uses should be considered carefully. Should we consider the use for drinking water or should we just use it for industrial and agricultural purposes? One proposal is to Ultra-treat and then pump into potable supplies. But have we thought this through enough, as many studies tell us that we have a very limited knowledge of the many different types of Viruses and Bacteria that are present in the water. In fact we know very little on the effect they have on us, treatment to destroy, and what treatment we have for infection if we were infected. For example to boil water kills blue green algae, but this also releases the toxins which is very harmful to us. We are still only identifying many of these issues, so how can we say it is safe to drink or what detrimental effects can they have on potable water sources. Should we add this to our drinking water like they do in Europe where bottled water is sold more than soft drink?

These questions remain:

Who will guarantee that the water is 100% safe and no detrimental effect will occur to destroy our entire water source?
What treatments do we have to safe guard us if we were infected?
What testing procedures can we use to monitor and ensure we will not be infected?
DO we have the treatment that can remove the nastiest even when we have little knowledge of them.

So far we can not be 100% positive on any of these questions, so why do we still consider drinking the water when we can use for so many other things.

One comment from the CSIRO, is that if we don't start drinking it the cost of water will go up. The truth however is that by treating and constantly monitoring too the level required the cost will be much higher then using for industrial and agricultural purposes. It is clear that these people have done studies, but have not done the cost-efficiencies very well.

This link is a Wastewater health study for the Queensland Government.

For many years now these systems have used, but have been misunderstood. This is simply due to the incorrect classification of systems. For example some refer to them as Land Application Areas (L.A.A) and other call them Subsurface Drip Irrigation Systems (SSDI). However they are not really either as they are part of the treatment process and nutrient removal. Land Application Areas by definition are any areas you apply something and could be a Mound, Trench, above ground sprinklers or any other form of dispersal. This is why the AS 1547 adds to the confusion and we need to reclassify these systems and the design parameters for each system. The Section 4.2.B in the A.S. 1547 should apply to any Low Pressure systems similar to trenched Drain-coil and Poly/PVC pipe with holes drill in to the wall or shallow trenched pipe and aggregate. A new classification should be Pressurized Subsurface Drip Disposal systems with Non or Pressure Compensated emitters and designed as per the manufacturers design Parameters. They should not be confused as a Gravity Fed Application Area. These systems are similar to what is being used on sports ovals and other turf applications, but they are not irrigation areas they only use an irrigation principle. For above ground spray or sprinkler systems then these must be designed differently again and should remain as with 4.2.B.

There is much more work required to be done with this, to ensure these systems are to ever work properly and eliminate the failures currently occurring.

We need to remember these systems are not just disposal systems, but a integral part of the treatment process. To many people think that they are just to get rid of the water, but in fact they actually allow the soil and vegetation remove nutrients and the beneficial bacteria in the soil treat the effluent.

This presentation is from Onsite 05 in Armidale NSW Australia.