2019/23: Menindee (NSW) – Blue Green Algae, Fish Kills, Foul Tasting Water, Motor Neuron Disease?, Trihalomethanes, Total Dissolved Solids

Menindee locals have ‘no faith’ in fish kill response

https://au.news.yahoo.com/menindee-locals-no-faith-fish-054538609.html

(Supplied to ABC: Graeme McCrabb)

March 21 2023

Outback NSW residents are frustrated, fed up and worried about their drinking water after the biggest fish kill on the Darling-Baaka River in memory.

Millions of native fish have washed up dead on the river at Menindee and downstream towards Pooncarie, in the state’s far west, since late last month as floodwaters receded and the region was hit by repeated heatwaves.

The mass fish kills were likely caused by low levels of dissolved oxygen in the water, known as hypoxic blackwater, which has been exacerbated by the extreme conditions.

 

After dead fish blanketed the water at the main weir late last week, police reassured residents their drinking supply was safe.

Emergency services and state government water authorities held a community meeting in Menindee on Tuesday morning to provide a possible timeline to remove and dispose of the animals and address concerns about water quality.

“There is no need for community concern as the initial assessment has determined multiple viable solutions to maintain water supply to the Menindee township and surrounds,” NSW Police said in a statement ahead of the meeting.

“The frequency of water quality testing has been increased to ensure it continues to meet the Australian Drinking Water Guidelines.”

Menindee local Graeme McCrabb said many felt the meeting provided no real answers.

“The only thing that was reiterated and certainly not taken with any faith from the community is that the water supply is safe and secure,” he told AAP.

“That is certainly not being accepted by the community at all.”

The Central Darling Shire council has been carting water to households that rely on the river for several days.

He said the community was doubtful about attempts to remove the fish because the water has become a “soupy mess”.

“As soon as you touch those fish now, they just break up. It’s a difficult one.”

Other residents told AAP they were too frustrated to attend the meeting after the 2019 fish deaths, and were skeptical about water management on the lower Darling-Baaka.

“There is anger there and frustration,” Mr McCrabb said.

“People have no faith that the government has the ability to respond or has any interest to respond.”

Federal and state agencies are working out of an Emergency Operations Centre set up in the outback town on Sunday.

NSW Police Assistant Commissioner Brett Greentree on Monday said the agencies’ first priority was protecting the water supply, but the clean-up effort could take some time.

“I can only appreciate and acknowledge the hardship,” Mr Greentree said.

“The smell is something for the poor residents to put up with and it’s really difficult after they’ve gone through a period of drought and then the floods.

“They’ve had a really tough time.”

Off-the-scale clean up as rotting fish threaten water

https://www.canberratimes.com.au/story/8128557/off-the-scale-clean-up-as-rotting-fish-threaten-water/

March 20 2023

Having endured droughts and floods, residents in outback NSW are dealing with the stench and clean up of millions of rotting fish as authorities work to protect drinking water.

Emergency crews face a logistical nightmare removing millions of dead fish from the Darling-Baaka River, after the worst mass death in living memory.

Huge clusters of dead fish have been found at Menindee and Pooncarie, in the state’s far west, as floodwaters receded and the region was hit by repeated heatwaves in recent weeks.

The fish kills were likely caused by low levels of dissolved oxygen in the water, known as blackwater hypoxia, exacerbated by the extreme conditions.

Authorities believe it is worse than the mass deaths during the height of the drought in 2019, when water flows were low or non-existent.

An Emergency Operations Centre was set up at Menindee on Saturday and specialist contractors will be sent in to remove as many fish as possible, police said.

Assistant Commissioner Brett Greentree said it was a priority to protect the water supply at Menindee and other communities along the river.

“I’m not making promises that all the millions of fish will be removed by contractors because that is a logistical nightmare and I need to be honest with the community of Menindee,” Mr Greentree told reporters in Dubbo on Monday.

Monitoring shows the drinking supply through the Menindee treatment plant is high quality.

The Central Darling Shire Council is carting water to households who rely on river water.

It will also arrange the disposal of the fish, approved by the NSW Environmental Protection Agency.

Mr Greentree hoped the removal operation could start as soon as possible.

“The Menindee community have had a real tough time of late when you look at the floods and now this as well,” he said.

“So it’s really important that we mobilise efficiently and as quickly as we can to do what we can to resolve this, but this is really a challenge against Mother Nature in many ways.”

A community town hall meeting will be held in Menindee on Tuesday to keep residents updated.

“I can only appreciate and acknowledge the hardship,” Mr Greentree said.

“The smell is something for the poor residents to put up with and it’s really difficult after they’ve gone through a period of drought and then the floods.

“They’ve had a really tough time.

“That is one of the reasons why we want to move this into gear very quickly, and get some respite for the town as soon as we can.

“Unfortunately, we need to be really honest. It’s not a quick fix, where we can do it in 24 hours.”

State and federal agencies are continuing to monitor risks to fish health.

Timing, size and location of water releases from the Menindee Lakes into the lower Darling-Baaka River may be used to maintain the water quality.

Toxic blooms and local fury: what’s going on at Menindee Lakes?

Despite months of a new river management strategy, the Menindee community is seething – and their water is turning green

https://www.theguardian.com/environment/2021/feb/14/toxic-blooms-and-local-fury-whats-going-on-at-menindee-lakes?

Feb 14 2021

This is the township of Menindee’s drinking water supply.

The pool behind weir 32 that provides water to the township of 600 turned green in January and a thick slime now covers up to a third of its surface.

WaterNSW has declared a red alert for toxic blue-green algae blooms at the weir, and for the lower Darling/Baarka for the 400km to its junction with the Murray.

The warnings advise people to avoid contact with the water. While the town has some filtration on its town water, it still smells bad. Those on properties and in small towns further south cannot safely drink the water, and there are warnings to monitor livestock.

This is despite the north-west of New South Wales receiving 14% more rain than average in 2020 and twice as much as 2018 and 2019 combined.

Locals like Graeme McCrabb say the Darling is now in as poor shape as it was in 2018, the year before the massive fish kills in January 2019.

“If we don’t get a major rain event in the next few months we’re looking at the same conditions next summer that led to the disaster,” McCrabb says.

So why, with good rainfall in the north, is Menindee facing yet another ecological crisis?

That’s what the Menindee community wants to know.

So angry are the local farmers, Indigenous population and the town that they have once again pulled stumps on any discussion with the NSW government over the Menindee Lakes plan, which is designed to return more water to the environment.

The stakeholder group representing 23 different local interests say they won’t be talking to the government until they can be provided with one of the basic necessities of life: safe drinking water.

“The issue here is critical water needs,” says the chairman of the stakeholder group, Terry Smith, who is also chair of the Pastoralists’ Association of the Western Darling.

“We keep getting told that this issue is out of the scope of the discussions about the Menindee Lakes project, but this is the most important issue to the community.”

The Menindee Lakes project, at a potential cost of somewhere between $800m to $1.2bn, is the NSW government’s marquee project to make water savings for the environment by using water more efficiently. The project, which would change the size and configuration of the lakes to make them smaller and deeper, aims to create water savings of 106GL a year through reducing evaporation.

But if NSW fails to deliver on its share of water savings by 2024, the state will likely face more buybacks of entitlements from agriculture. This would almost certainly mean that farmers in the rich cotton growing areas to the north would be required to reduce irrigation – a move that is strongly opposed by some of the most powerful farming interests in the country.

New water resource plans designed to address water shortages in the Darling have been operating in NSW since the middle of last year. So why are communities like Menindee still facing dire shortages?

The new water plans are designed to address many of the shortcomings of the old plans, including protecting low flows in the river from being pumped for irrigation further upstream from Menindee, and protecting the first flushes of the river after rain.

But seven months into the new rules, the Menindee residents say they don’t go far enough. McCrabb and other locals believe the real problem still lies in the government’s failure to address over-extraction by irrigators upstream and unregulated harvesting of floodplain water, which has caused a major drop in the amount of water actually reaching the river.

Flows are barely reaching Menindee and the lakes have not been allowed to recharge – they are at 18.3%, meaning that there will be little scope to send water down the river next summer if it remains dry.

So the community is boycotting discussions on the big ticket item that the NSW government wants: their support for the Menindee Lakes project.

“Until the issue of equitable water share for the entire Darling/Baarka is addressed, the proposed changes at Menindee of the [Menindee Lakes] project will have no support from the Lower Darling community. The community quite rightly expect the base needs of the river to be covered first,” Smith wrote in a letter to the local press.

Smith tells the Guardian: “There’s little point in building the Mendindee Lakes project if the lakes are only likely to fill intermittently – perhaps as infrequently as every 15 years.

“Why build the project at Menindee when you can’t run the river? There is no benefit for the community, for the culture, for the economy. People at Menindee just want their water back.”

The government’s first proposal for managing the lakes has now been abandoned after it became clear the planned construction of a new regulator – a structure to control flows – at the junction of Menindee and Cawndilla lakes would destroy one of the most important Indigenous sites in NSW.

The new plan, involving adding four metres in depth to the two northern lakes by building banks around them, is controversial for other reasons. There are questions of flooding of farmland, the cost, Indigenous sites and the fact that the government still hasn’t factored in the last 20 years of data on inflows.

McCrabb says it is also expensive. The cost of the water saved by the project will be $20,000 a megalitre, compared to the market value of an A class licence pre-drought of $1,500 a megalitre.

But for now, the question is the water supply.

“If this debacle was happening on the other side of the hills, there would be an outcry,” Smith says.

A spokesperson for the NSW water minister, Melinda Pavey, said the government would soon consult with communities on the western regional water strategy and was “open to speaking further about water quality in the lakes”.

“We have already written to the advisory group indicating this will be the best forum to discuss connectivity and water quality,” the spokesperson said.

“WaterNSW is currently forecasting between 13,000ML and 20,000ML will flow over the weir at Wilcannia by the end of February, with as much as 10,000ML flowing into the Menindee Lakes.”

February 2019 – Menindee (New South Wales) – Blue Green Algae

https://tendaily.com.au/shows/theproject/exclusive/a190210prg/do-australian-lakes-and-rivers-contain-a-toxin-that-may-cause-mnd-20190210

We explore the link between NSW waterways and a toxin that might trigger MND.

Professor Dominic Rowe of Macquarie Neurology says, “From 1986 to 2016, there’s been a 250% increase in Motor Neurone Disease as a cause of death in Australia and that can only be environmental…”

Research overseas has linked the neurotoxin BMAA, a by-product of blue-green algae, to MND. This toxin was recently discovered in Lake Wyangan in NSW.

It’s also been found in a number of other drought-affected New South Wales waterways, including along the Darling River.

Professor Rowe says, “If we can understand what in the environment triggers Motor Neurone Disease, conceivably we could prevent [it] from even occurring.”

Tim Trembath, an MND sufferer, lives at Lake Cargelligo, which is 140-kilometers north of Griffith. He’s spent a lot of time at this lake, where there’s been an outbreak of blue-green algae.

Tim says, “Up until about 2010, the lake water was the water that was used for drinking and washing in the town.”

The disease has stripped Tim of his ability to ride his motorbike and he needs regular care. Two of his friends in the 1500-resident town have died from MND.

“Anyone who lives in this town has probably swum in the lake, and the lake has algal blooms in it nearly every summer.”

While it’s easy to assume there’s a link between these waterways and MND, Professor Rowe says, “It is highly unlikely that there’s going to be one specific environmental trigger, it’s likely to be a combination of factors.”

Menindee locals living with ‘disgusting’, ‘filthy’ tap water that smells like ‘a sewer’

https://www.abc.net.au/news/2019-01-16/menindee-locals-living-with-filthy-tap-water/10717744?fbclid=IwAR1F6jEtabanGilGpWicKydg0n-eExy3LDrxTfC8xkjt6EahfNuebU8Agc8

If your tap water was the colour of mud, would you drink it?

Menindee locals in far-west New South Wales say that is what they are being forced to endure.

“This is the disgusting water coming out of our tap today,” Taya Biggs wrote in the Menindee Region Community Group on the Darling River Facebook group.

“They expect us to wash, drink, cook and wash our clothes in the filthy water.”

Another person wrote: “My bathroom water is green. Spewed in the shower again from the stench”.

The town has been in the headlines this week after a million fish were found dead along 40-kilometre stretch of the Darling River at Menindee, near Broken Hill, as a result of a toxic algal bloom.

Ms Biggs’s post has been shared almost 3,000 times.

Her mother Daphne Biggs said while they “don’t have any choice” but to shower in town water, they rely on rainwater for everything else although she expects that will only last another two months.

“The smell [of the tap water] is absolutely disgusting,” she said, adding that no-one in her house had drunk the water for two years.

Locals say water makes them sick

Life-long Menindee local Dorothy Stephens said the water — supplied by Essential Water — has made her sick.

“Right up until Christmas I was still boiling that water and drinking it and then I worked out I was getting diarrhoea from it, so we stopped,” she said.

She is not alone. Ngiyampaa elder Beryl Carmichael has lived in Menindee for 84 years.

“I drink rain water, otherwise I’d be running to the toilet,” she said.

Essential Water to blame says tourism body

President of the Menindee Tourism Association Rob Gregory said the water coming out of the taps was “pretty brown”.

“Prior to the first fish kill, our water had a smell to it which was sort of like a dammy, old, muddy smell that wasn’t too bad,” he said.

“But then straight after the first kill, it started to smell like sewer.”

He said he was “disappointed” with Essential Water.

“Even after the first kill, [they] didn’t even put a media release out to say that the water’s okay,” Mr Gregory said.

“We’re paying top dollar for that water and what are we getting? Second grade, third grade quality; it’s not good enough.”

Essential Water stands their ground

Despite locals’ concerns, Essential Water is defending the quality of water being supplied to the town.

“We’ve received only two water complaints of coloured water at Menindee,” head of operations John Coffey said.

He said both visits resulted in “minor flushing” and said water samples taken at the sites “complied with the requirements of the Australian Drinking Water guidelines”.

“So it was certainly an isolated incident,” Mr Coffey said.

He said Essential Water sourced water from the Darling River, Lake Copi Hollow, and the Menindee common bore.

Mr Coffey refused to say what triggered Essential Water’s water source switch from the Darling River to Lake Copi Hollow in December 2018.

“The choice of raw water supply to the Menindee Treatment Plant is based on raw water quality at the time,” he said.

He said anyone with complaints of poor water quality should contact Essential Water on 13 23 91.

Brown tap water across Western NSW deserves state of emergency response

By Roy Butler and Helen Dalton

The NSW Government must supply and distribute free bottled water across the growing number of rural towns unable to drink their tap water.

It’s only fair government step in to help those enduring third world living conditions, due to government draining of lakes and mismanagement of our river system.

Brown water crisis

The small town of Billmari, near Cowra, is one of several towns where potable water is too dangerous to drink.

Ironically, Billmari is an Aboriginal word meaning ‘plenty of water’.

Menindee now has plenty of brown water coming out of taps. Menindee is where locals begged governments not to drain their lake in 2017, because the lake supplies their drinking water. Governments ignored them.

Residents in Wilcannia, Hay, Cootamundra, Ganmain, Coolah and Yass have also reported foul-tasting tap water to us.

Walgett has faced such severe drinking water restrictions that generous Dubbo residents have supplied them with bottled water via a Facebook campaign.

But why are drought-stricken neighbouring towns carrying the can for the governments who caused this mess?

Last weekend, NSW Premier Gladys Berejiklian went to Coogee Beach. She pledged millions of dollars to clean the beach swimming water there.

It’s now time for Gladys to come out west to help those who can’t even drink the tap water.

State of emergency time

If an oil spill poisoned a river, killing one million fish and robbing towns of their drinking water, the NSW Government would declare a state of emergency.

This would force government agencies to get out to affected areas; and help the many residents who can’t afford expensive bottled water.

Under NSW state law, the Premier can call a state of emergency due to: fire, flood, storm, earthquake, explosion, accident, epidemic or warlike action which endangers people’s health.

This law needs to be changed, to include man-made disasters — like governments draining a town’s supply of drinking water during a drought —  in the list of emergencies.

There are several state government departments that administer water, employing thousands of bureaucrats.

Why not get them out to Menindee, Walgett, Billmari and other affected towns, to set up water hubs and to distribute free bottled water?

It’s the least the government could do.

Royal Commission next

We’ve both traveled to third world countries like Papua New Guinea, India and Cambodia. Not being able to drink the tap water was the biggest difference between those places and Australia.

That’s why it’s disgraceful we’ve let things come to this in our regional towns.

Clean drinking water should be the number one priority of any civilised nation, ranking well above Sydney stadiums and beaches.

This is why we urgently need a federal royal commission into how governments manage our rivers.

A royal commission will expose the government’s bad decisions on draining lakes; and flush out wealthy National Party donors who rort the system.

But Royal Commissions can take years, and we have a crisis now.

The state government needs to get cracking. It’s time for immediate state of emergency-style provision of free bottled water to towns like Menindee, Walgett and Billmari, where tap water is too dangerous to drink.

Roy Butler is the SFF candidate for Barwon. Helen Dalton is the SFF candidate for Murray.

Related: Politicians should face criminal charges over million fish kill

Motor neurone disease link to algae toxin exposure a developing path of research, scientists say

March 28 2019: https://www.abc.net.au/news/2019-03-28/scientists-say-link-between-algae-and-mnd-needs-further-look/10943826

Menindee resident John Brereton has a theory about what caused his wife, Pam, to develop motor neurone disease (MND), and it is a path that scientists are investigating.

Key points:

  • Research suggests toxin in blue-green algae blooms may increase neurological diseases
  • Incidence of MND in Griffith is seven times higher than the national average
  • CEO of MND NSW is not convinced of link between blue-green algae and MND

Up to 2,000 Australians are estimated to have MND, but diagnosis is painstakingly difficult because researchers are not yet sure how the disease is triggered.

“I couldn’t really say for certain, but I do believe the blue-green algae has got something to do with it,” Mr Brereton said.

Recent research, too, has pointed to environmental toxins such as those found in blue-green algae for a range of neurological diseases.

Ms Brereton grew up in Ballarat, near Lake Wendouree, which experiences algal blooms like many waterways in Australia.

John and Pam Brereton also lived in the Darling River town of Menindee for 19 years and used river water for cleaning and bathing, but drank filtered rainwater.

Menindee, in far-west NSW, was the scene of mass fish kills over summer, which the Department of Primary Industries said were caused partly due to blue-green algae.

“The algae has killed the fish. It’s killing everything, actually,” Mr Brereton said.

Fears in Menindee reflect those of people in Griffith in central NSW, where the incidence of MND is seven times higher than the national average, according to recent research.

The common link between the towns is proximity to a water source that is frequently beset by outbreaks of blue-green algae.

However, the CEO of the Motor Neurone Disease Association of NSW (MND NSW) Graham Opie is not convinced.

“There are so many theories. The fact is we just don’t know what causes or triggers MND,” he said.

Can BMAA cause motor neurone disease?

Blue-green algae, or cyanobacteria, are the oldest living organisms on the planet precisely because they are good at out-competing others by releasing toxins.

What’s known about link between BMAA and MND:

  • BMAA is a neurotoxin found in cyanobacteria, also known as blue-green algae
  • BMAA affects the neurological function of the brain by causing protein misfolding
  • Protein misfolding is a key characteristic of neurological disease
  • Scientists say while there is a link between BMAA and MND, more research is needed to determine the risk associated with exposure

One of these is the neurotoxin BMAA.

Dr Ken Rodgers from the Neurotoxin Research Group at the University of Technology Sydney specialises in environmental neurotoxins and how they interfere with the body’s functions.

“I think people should be worried. I get contacted regularly by people who have MND and have had obvious exposure to cyanobacteria,” Dr Rodgers said.

 

Cyanobacteria are always present in rivers and lakes, but only bloom into blue-green algae when conditions are favourable.

Low water flows, high temperatures, and nutrient build-up from agricultural run-off are all factors that contribute to algal blooms.

“I’m not trying to be alarmist,” Dr Rodgers said.

“Algal blooms are dangerous, but they’re being monitored by professionals so just follow the guidelines.”

Alerts issued by water authorities stipulate that people should not swim in, drink from, or eat seafood from algae-affected waterways.

Dr Rodgers said governments should be doing more than that to mitigate risk.

“You’ve got to try to take away the risk, even if it’s not going to affect everybody,” he said.

“Governments have got to start looking after the waterways, keep flows going, stop allowing big companies to dump chemicals into the waterways.”

More research needed

Mr Opie of MND NSW said there had been no recorded increase in its membership base in the far-west of NSW, an area struck by repeated blue-green algae events in its waterways.

“We’ve had fairly constant numbers, and those numbers haven’t changed in the 13 years I’ve been with the organisation,” he said.

Dr Rodgers said that just because toxins may be present in the water, it did not mean people exposed to blue-green algae would get sick.

 

“Someone who smokes from 16 to when they’re 100 years old doesn’t disprove that smoking causes cancer, it just shows that some people have resistance genes, and some have susceptibility genes,” he said.

“It’s the same story with exposure to environmental toxins.”

But he believed “there’s no question that BMAA can cause neurological disease”.

“The question is — how big is the risk and what makes you susceptible?” Dr Rodgers said.

He is calling on governments to invest more research dollars into the environmental factors that may trigger MND.

“What we’re trying to do is understand how the toxin affects us, and from there we could try to work out what the susceptibility genes might be,” he said.

Mr Brereton of Menindee said he believed he would never know exactly why his wife got sick, but hoped that some day the cause would become clear.

“She was a fit woman all her life, worked, never had any illnesses, and then all of a sudden — bang,” he said.

“I just hope that no-one has to put up with it. It’s a very cruel disease.”

Menindee locals worried about water waiver

https://www.sbs.com.au/news/menindee-locals-worried-about-water-waiver

6/8/19

Rural residents living outside Menindee are being asked to sign a waiver to have potable water delivered to their homes.

In summer the river water at Menindee killed millions of fish.

Now, as the drought drags on through winter, residents outside of the remote NSW town are being forced to sign a document stating they won’t sue authorities if the drinking water delivered to their homes makes them sick.

Rob McBride and his family live on the sheep property Tolarno Station on the banks of the Darling River some 50 kilometres south of Menindee.

For years the family sourced their drinking water from the river and rainwater tanks, but now they are reliant on water delivered by charities, or they buy potable water from the local council.

Central Darling Shire Council will only deliver water to Tolarno Station, however, if the McBrides sign a document guaranteeing they won’t sue the council or the state government if they become sick.

“It’s blackmail and you can’t do that,” Mr Mcbride told AAP.

“If you don’t sign that paperwork then you don’t get any water supplied to your house and your family. We’ve got a gun to our head.”

Mr McBride is worried blue-green algae in the town’s main water sources could be linked to the “soul-destroying” motor neurone disease.

Menindee’s town water, and the water delivered to nearby rural residents, is sourced by Essential Water from Lake Copi Hollow which at present has an amber alert for blue-green algae.

Central Darling Shire Council’s website says its potable water is safe to drink.

The council is responsible for carting the water to the rural residents. It says those who supply the potable water are required to provide the NSW health department with regular samples to ensure it meets Australian guidelines.

Essential Water insists the water it supplies is treated and tested to ensure it complies.

But, according to Macquarie University neuroscientist Gilles Guillemin, some cyanotoxins – which are produced by blue-green algae – are so small they can’t be filtered out.

Professor Guillemin has been working since 2012 on developing technology to help quantify the toxins and identify exactly what it is about in blue-green algae in the water that triggers MND.

“I wouldn’t drink the water, if I go there (to Menindee), I would drink bottled water,” he told AAP.

But council general manager Greg Hill says residents are only asked to sign the waiver because the potable water is delivered “into a tank we have no control over”.

The tanks on most properties previously held raw or untreated water from sources like the Darling River, which means they could be contaminated, Mr Hill told AAP.

“For this reason council asks that waiver be signed as we have no control over the maintenance and the cleanness of the storage tanks,” he said in a statement.

Retiree Dick Arnold lives “a stone’s throw” from Menindee and was also required to sign a waiver before potable water was delivered to his home.

That was the case even though he recently received a brand new water tank paid for by the state government.

“We certainly don’t drink it,” he told AAP. Instead, the water is used for washing.

Mr Arnold says he’s never been asked to sign such a document before.

“It does make you wonder what’s in the water. You can’t trust anyone these days.”

Both Mr McBride and Mr Arnold are concerned the water may contain traces of blue-green algae blooms which are also present in the Darling River and were blamed for the catastrophic mass fish kills in December and January.

“MND is a soul-destroying, debilitative and murderous disease,” Mr McBride said.

“And the government gives us a disclaimer which effectively relinquishes them of all responsibility for future generations.”

Menindee (New South Wales) – Trihalomethanes

1/1/19 – 31/3/19: Menindee (New South Wales) Trihalomethanes – 247μg/L (Highest detection), Total 134μg/L (av. detection)

Trihalomethanes Australian Guideline Level 250μg/L (0.25mg/L)

Why and how are THMs formed?
“When chlorine is added to water with organic material, such as algae, river weeds, and decaying leaves, THMs are formed. Residual chlorine molecules react with this harmless organic material to form a group of chlorinated chemical compounds, THMs. They are tasteless and odourless, but harmful and potentially toxic. The quantity of by-products formed is determined by several factors, such as the amount and type of organic material present in water, temperature, pH, chlorine dosage, contact time available for chlorine, and bromide concentration in the water. The organic matter in water mainly consists of a) humic substance, which is the organic portion of soil that remains after prolonged microbial decomposition formed by the decay of leaves, wood, and other vegetable matter; and b) fulvic acid, which is a water soluble substance of low molecular weight that is derived from humus”. Source: https://water.epa.gov/drink/contaminant

Menindee – New South Wales – Total Dissolved Solids

1/1/19 – 31/3/19: Menindee (New South Wales) Total Dissolved Solids – 1206 μS/cm (Highest detection), Total 1098 μS/cm (av. detection)

GUIDELINE

“No specific health guideline value is provided for total dissolved solids (TDS), as there are no
health effects directly attributable to TDS. However for good palatability total dissolved solids
in drinking water should not exceed 600 mg/L.

Total dissolved solids (TDS) consist of inorganic salts and small amounts of organic matter that are dissolved in water. Clay particles, colloidal iron and manganese oxides and silica, fine enough to pass through a 0.45 micron filter membrane can also contribute to total dissolved solids.

Total dissolved solids comprise: sodium, potassium, calcium, magnesium, chloride, sulfate, bicarbonate, carbonate, silica, organic matter, fluoride, iron, manganese, nitrate, nitrite and phosphates…” Australian Drinking Water Guidelines 2011