Treated Sewage, Would You Drink It? (Part 2)

Part 1 looked at the why and how of recycling sewage to drinking water.  The technology is operating around the world, effectively and acceptably, for example in a plant in Orange County, California amongst others.

So, what causes resistance to this technology?

"It is quite difficult to get the cognitive sewage out of the water, even after the real sewage is gone."

- Carol Nemeroff, psychologist

So, what does that mean?

Manhole cover, Rome, Italy

Basically it means that despite the fact that the recycled water is purer than normal source water, once it's had poo in it, that thought lingers long after the smell has gone.  This is a problem that needs to be overcome when you think how little fresh water is available in the world.

On a planet that's seventy percent water it is estimated that only 3% of all water is fresh water and of that, with so much tied up in ice caps, glaciers and ice bergs, only 1% of the water is readily available. 

With the burgeoning human population the demand on this precious resource for both drinking and for watering the crops and livestock that will feed us will only increase.

A professor in the US, Brent Haddad thinks that this method of producing fresh water is a rational way forward stopped by irrational objections from the public.  He realised that this was more of a problem for psychologists than engineers. 

In a study of 2000 people he asked why people had such a problem drinking recycled sewage.  His study showed that 60% of those surveyed would not touch this type of water.

Likewise in a 2007 referendum, in Toowoomba in Queensland, Australia, more than 61% of the eligible 60,231 voters voted against the proposal to build a treatment plant to augment their water supply.  This is despite the fact that the city had experienced severe water restrictions that banned the use of town water on lawns, and eventually gardens and potted plants.

However, there are places in the world where this is being done today.

Windhoek, the capital of Namibia uses recycled water for drinking water during times of drought.

The South African cities of Scottsdale, Pretoria and Cape Town rely on indirect schemes, where recycled sewage is introduced back into a river, dam or aquifer.  There it mixes with the rest of the water before being retreated for drinking, effectively taking the poop factor out of the equation.

In Singapore, about 1% of recycled sewage water is used for drinking.

Perth water Corporation advanced treatment plant

In Perth in Western Australia, the Perth Water Corporation has a pilot plant operating producing drinking quality water.  They are removing the “poo” factor by discharging into aquifers where it co-mingles with ground water and is later pumped out and treated as part of the normal supply.

Approval to discharge was granted on 9th November 2010 and as at the end of August 2011, 872 megalitres have been injected into aquifers.

The trial is being overseen by the WA Department of Health, WA Department of Water and WA Department of Environment and Conservation.   

It is partly-funded by the Australian Government’s Water For the Future initiative.

Using LinkedIn, I asked my contacts to answer the following question from 4 options:

WOULD YOU DRINK TREATED SEWERAGE?

1.      No way, no matter how it was treated

2.      Yes, water is precious we should reuse

3.      Maybe, if it was mixed with pure water

4.      Only water is in short supply

I’ll share the results later when the poll closes but if you look at the right of the page, you can click to vote too.

When you think about it, all water has been sewage at one point in time.  Everyone lives downstream of someone or something, even animals poo and pee in our rivers and dams.

Some major towns in Australia are taking their source water from rivers that are having treated sewage discharged upstream of them.

So, we are already drinking sewage of one type or another, so isn’t producing this proven, technically competent manner a method that should be incorporated into any sustainable water management policy?

Treated Sewage, Would You Drink It? (Part 1)

Photo by  Tomas Castel

Drought is a part of life in Australia.  Our great rivers, the Murray Darling System, the Murrumbidgee and others are often little more than sluggish brown streams.  Salt laden, polluted and full of nitrates from fertiliser run off, this is where much of Australia’s drinking water comes from.

The water management strategies employed by our politicians often seem to be aimed at giving history the opportunity to remember the politicians for the landmark projects they created rather than remembering them for developing effective and inclusive strategies that provide real results and benefits for the environment.

Desalination seems to be regarded by many as the panacea for all that ails our water systems while storm water harvesting and treating sewage to recycle as drinking water are often overlooked.

Treated sewage provides a convenient resource and here’s how it could get from the home back to our tap.

In large cities around the globe, sewage and waste-water is collected from homes and storm-water drains via a sewerage system and then it gets processed at a treatment plant.


At the first stage the sewage passes through a filter to remove large materials like tree limbs, garbage, plastics and large organic matter.  From there it passes to the primary sedimentation tank, where sludge settles to the bottom and lighter liquids like grease, oil and soap rise to the top. The surface is skimmed off while the sludge is pumped away to a separate treatment facility.

From there, it’s pumped to another tank where bacteria breaks down any remaining organic matter in the wastewater, oxygen is pumped into the fluid to encourage the bacterial activity. The next step is more filtering, microfiltration that removes suspended solids, protozoa, bacteria, and some viruses.

The last step is to disinfect the water, often by the addition of chlorine, hydrogen peroxide and other chemicals and by running it past high intensity ultraviolet lights.

Image via WikipediaFrom here it can be “shandied” into the water supply pipeline or other ways like a river, or pumped into the ground, where it is reintroduced into the below-ground water supply.

Years later, after natural filtration, the water is extracted as part the wider supply network.  It is all treated together as part of our domestic water supply.

 So, what’s the problem with this?  The treated water itself is often cleaner (purer) than the original source water before treatment. 


Almost everyone lives downstream of someone or something, so the raw product that's turned into our drinking water today isn't so pristine after all.

As reported in the Melbourne Age in 2008:
"The Victorian government is opposed to the drinking of recycled sewage, despite a study in 2006 finding it could be done in Melbourne at less financial and environmental cost than seawater desalination.
Despite the policy ban, many Victorian towns along the Murray River effectively drink recycled sewage already, by taking their drinking supplies from rivers that are boosted by the treated wastewater of towns upstream."


Maybe taking a long, hard and rational look at this technology isn't such a bad idea?

The technology exists and is at work in places like Orange County, California, so it’s not a technical issue that's stopping the wider adoption of this alternative, it’s all psychological and part 2 delves into this issue.

Modern Environmental Vandalism

Image via WikipediaIn the short time that Europeans have been coming to Australia, they have been unleashing a never ending series of feral animals on the native landscape.

Animals such as cane toads, foxes, rabbits; weeds such as salvation jane, thistle and blackberry have been introduced, all of which have significant environmental and financial impacts on the Australian landscape.

It seems that we cannot learn from the mistakes of the past

Feral deer in South Australia are an ever increasing problem that continues to have an impact on native flora and fauna.

Image via WikipediaDeer have been found in the Waite and Brown Hills Creek Reserves as well as the South East of SA.

Red and Fallow deer species are the most prevalent although 6 species of deer are found in lesser numbers.  Most of the deer are descended from animals that have escaped from commercial herds.

Biosecurity SA state:  "Deer in large numbers threaten environmental and agricultural values and public safety."

Deer pose a number of problems to the Australian native flora and fauna.  Deer graze or browse native vegetation and grasses and kill young trees through constant rubbing with their antlers, especially during the rut.

These deer also trample the mounds of the Malleefowl, a species listed as vulnerable.

Despite increasing education and the profile that environmental issues have in Australia, the lessons of the past regarding the impact that introduced species can have on the native habitat continue to be ignored.

Those who believe that deer are "cute and should be left alone" are perpetrating the worst kind of modern environmental vandalism.

Research for an article

HELP, I am doing some research for an article and here's your opportunity to help.

I've posted a pole on LinkedIn and there's a widget here for you to vote and have your say.

Thanks

An Orwellian Approach To Social Media

Politicians only know one of two ways to react to a situation, there is the tried and trusted knee jerk reaction or the equally time tested method where they simply bury their head in the sand.

In the Middle East and North Africa, China and many other countries around the world with poor human rights records, social media sites have suffered at the hands of regimes taking the sledgehammer approach to dissent and protest. Now it seems in the UK that the Government wants to follow suit and censor or shut down or limit access to social media and other types of messaging services.

Image via WikipediaThat the violence recently experienced in the UK was despicable and mindless is without question.  The issue now is: Do the Government of David Cameron and the Metropolitan Police really have the answers to the questions that are being asked of them now?

If the organisers were as sophisticated as the UK Government are telling us,  limiting access to any social media or messaging service is a waste of effort.  Users all over the world in countries with far more insidious control of their people have found ways to side step imitations imposed by Governments.  

Sidestepping the Cameron approach could simply be a matter of creating a new account, not something terribly difficult for the average 7 year old, let alone someone who has an agenda.

What is also being overlooked in this approach is that neither the social media sites or the messaging services are really broadcast services.  People interact with those they are following, or already within their network so the illusion of mass broadcasting of invitations to pillage the local shops are exactly that, illusions. 

Mind you, the UK Government is only treading the same path as authorities do in the US when they want to limit protests.  In San Francisco recently the Bay Area Rapid Transit system, better known as BART, shut down mobile phone towers to limit protests against after a police shooting.  In the article on NPR.ORG, it is reported that authorities limited the phone reception for 3 hours to control the protest, there is no suggestion in the article that the authorities thought that the protest would turn violent or endanger life in any way.

Playing shoot the messenger isn't going to work, especially when the same social media sites and messaging services are being used by volunteers to clean up after the violence.

Sun Causes Phone Problems

Image via Wikipedia

 If your mobile phone drops out over the next few days, for a change it may not be Telstra's fault. 

Three large explosions on the surface of the sun have seen US Government officials issue advisories warning of disruptions to satellites that provide telecommunication and GPS services.

Despite advances in protection systems, major electrical grids are also vulnerable to these events.

A solar flare becomes a problem for the Earth when the flare and associated coronal mass ejection are pointed in our direction.

The first of these storms passed the Earth on Thursday with little impact but the one passing now is stronger.  The effects of the third could be to amplify the effects of the second storm on the Earth’s magnetic field.

Scientists at the US Space Weather Prediction Centre predict the next peak in solar activity, known as a solar maximum, to occur in 2013.