Why did a Canadian town’s water supply turn pink?

Pink water. Image: Magic Momentz/Flickr/creative commons.

Most of us take it for granted that the taps in our homes will deliver safe and clean water for drinking, cooking, showering and cleaning. This means there is usually little interest from the public in how the water gets there. However, it took less than a day for a story from Onoway, a small town in Alberta, Canada, with just over 1,000 residents, to make it from social media to global newsfeeds. “Bright pink water comes out of taps in Canada!” – suddenly we are all interested in water treatment methods. The Conversation

To enjoy the benefits of clear and safe water, a hidden but valuable infrastructure of water treatment exists in our cities and villages. These are operated and maintained by engineers and scientists, and among them are water chemists. These chemists have been investigating the use of neat chemical reactions to remove undesired chemicals and potential pathogens from naturally sourced water and to prepare the water for its safe journey through distribution systems.

The local drinking water treatment plant of Onoway treats its water using potassium permanganate. This is an almost black looking solid which forms a bright purple solution in water and also removes dissolved iron and another metal called manganese.

Iron and manganese are not harmful to human health, but if these metals are present at high concentrations it can lead to deposits in the water distribution system and discolouration of the water. However, the auburn tints of iron seem boring compared to the spectacular pink that has raised global interest and lively social media discussions.

Customers are very sensitive to the colour, taste and odour of drinking water – these are the human senses used to assess water quality – so this incident has understandably caused alarm. The pink colour stems from some potassium permanganate that escaped through a failed valve and into the drinking water distribution system, eventually ending up with the customers.

Potassium permanganate has been used in drinking water treatment for more than 100 years. In addition to iron and manganese removal, it is used to remove taste and odour as well as to control undesired algal or mussel growth in treatment works. It also has disinfecting properties. Permanganate forms solid, black manganese dioxide when it reacts with the water contaminants – and this can then be filtered out of the water.


A little goes a long way

Potassium permanganate has the chemical structure KMnO4 and is a compound that is electron deficient – that is, it doesn’t have enough electrons. This lack of electrons makes it a strong oxidant that readily reacts with a wide range of unwanted compounds in water. It belongs to an established group of water treatment chemicals that can be summarised under the term “conventional chemical oxidants”, which also include oxygen, chlorine, chlorine dioxide, ozone, hydrogen peroxide and, in the wider sense, UV light.

Water is typically treated with a dose of 1-3mg of potassium permanganate per litre of water, which is quite a small amount. But only unreacted potassium permanganate has a visible pink colour in water and is visible even at very low concentrations – as low as 0.05 mg per litre of water – so it doesn’t take much to add colour.

Since only small quantities of permanganate can change the colour of water, customer complaints relating to residual permanganate are known to occur . This means treatment works usually take care to remove any unreacted, coloured permanganate before the water reaches consumers.

The pink water does not pose a threat to human health but skin irritation related to potassium permanganate is known at a certain concentration. Onoway’s mayor claimed that customers were not at risk. However, these concentrations seemed to vary – some had water merely tinted pink whereas some water was bright purple. Regardless of what shade of pink they receive, customers are advised to rely on alternative drinking water sources until the permanganate is flushed out of the distribution system.

Water treatment isn’t simple

For water treatment, there is no one-size fits all approach. Drinking water treatment processes vary due to different local water resources and what the traditional and established technologies are. Iron and manganese can be removed by alternative methods, such as aeration, which uses the oxygen present in the air, or by running the water over catalytic granules consisting of manganese dioxide. But every method has its specific advantages and disadvantages.

Many parameters need to be evaluated before making an informed decision on which method to use to treat a water supply – but there’s no doubt that potassium permanganate is one of the more colourful methods.

Jannis Wenk is a lecturer in water science and engineering at the University of Bath.

This article was originally published on The Conversation. Read the original article.

 
 
 
 

A nation that doesn’t officially exist: on Somaliland’s campaign to build a national library in Hargeisa

The Somaliland National Library, Hargeisa. Image: Ahmed Elmi.

For seven years now, there’s been a fundraising campaign underway to build a new national library in a nation that doesn’t officially exist. 

Since 2010, the Somali diaspora have been sending money, to pay for construction of the new building in the capital, Hargeisa. In a video promoting the project, the British journalist Rageeh Omar, who was born in Mogadishu to a Hargeisa family, said it would be... 

“...one of the most important institutions and reference points for all Somalilanders. I hope it sets a benchmark in terms of when a country decides to do something for itself, for the greater good, for learning and for progress – that anything can be achieved.”

Now the first storey of the Somaliland National Library is largely complete. The next step is to fill it with books. The diaspora has been sending those, too.

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Some background is necessary here to explain the “country that doesn’t exist” part. During the Scramble for Africa of the 1880s, at the height of European imperialism, several different empires established protectorates in the Somali territories on the Horn of Africa. In 1883, the French took the port of Djibouti; the following year, the British grabbed the north coast, which looks out onto the Gulf of Aden. Five years after that, the Italians took the east coast, which faces the Indian Ocean.

And, excepting some uproar during World War II, so things remained for the next 70 years or so.

The Somali territories in 1890. Image: Ingoman/Wikimedia Commons.

When the winds of change arrived in 1960, the British and Italian portions agreed to unite as the Somali Republic: a hair-pin shaped territory, hugging the coast and surrounding Ethiopia on two sides. But British Somaliland gained its independence first: for just five days, at the end of June 1960, it was effectively an independent country. This will become important later.

(In case you are wondering what happened to the French bit, it voted to remain with France in a distinctly dodgy referendum. It later became independent as Djibouti in 1977.)

The new country, informally known as Somalia, had a difficult history: nine years of democracy ended in a coup, and were followed by the 22 year military dictatorship under the presidency of General Siad Barre. In 1991, under pressure from rebel groups including the Hargeisa-based Somali National Movement (SNM), Barre fled, and his government finally collapsed. So, in effect, did the country.

For one thing, it split in two, along the old colonial boundaries: the local authorities in the British portion, backed by the SNM, made a unilateral declaration of independence. In the formerly Italian south, though, things collapsed in a rather more literal sense: the territory centred on Mogadishu was devastated by the Somali civil war, which has killed around 500,000, displaced more than twice that, and is still officially going on.

Somalia (blue) and Somaliland (yellow) in 2016. Image: Nicolay Sidorov/Wikimedia Commons.

The north, meanwhile, got off relatively lightly: today it’s the democratic and moderately prosperous Republic of Somaliland. It claims to be the successor to the independent state of Somaliland, which existed for those five days in June 1960.

This hasn’t persuaded anybody, though, and today it’s the only de facto sovereign state that has never been recognised by a single UN member. Reading about it, one gets the distinct sense that this is because it’s basically doing okay, so its lack of diplomatic recognition has never risen up anyone’s priority list.

Neither has its library.

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Rageeh Omar described the site of the new library in his fundraising video. It occupies 6,000m2 in the middle of Hargeisa, two minutes from the city’s main hospital, 10 from the presidential palace. In one sequence he stands on the half-completed building’s roof and points out the neighbours: the city’s main high street, with the country’s largest shopping mall; the Ministry of Telecoms that lies right next door.

This spiel, in a video produced by the project’s promoters, suggests something about the new library: that part of its job is to be another in this list of landmarks, more evidence that Hargeisa, a city of 1.5m, should be recognised as the proper capital of a real country.

But it isn’t just that: the description of the library’s function, in the government’s Strategic Plan 2013-2023, makes clear it’s also meant to be a real educational facility. NGOS, the report notes, have focused their resources on primary schools first, secondary schools second and other educational facilities not at all. (This makes sense, given that they want most bang for their buck.)

And so, the new building will provide “the normal functions of public library, but also... additional services that are intentionally aimed at solving the unique education problems of a post conflict society”. It’ll provide books for a network of library trucks, providing “book services” to the regions outside Hargeisa, and a “book dispersal and exchange system”, to provide books for schools and other educational facilities. There’ll even be a “Camel Library Caravan that will specifically aim at accessing the nomadic pastoralists in remote areas”.

All this, it’s hoped, will raise literacy levels, in English as well as the local languages of Arabic and Somali, and so boost the economy too.

As described. Image courtesy of Nimko Ali.

Ahmed Elmi, the London-based Somali who’s founder and director of the library campaign, says that the Somaliland government has invested $192,000 in the library. A further $97,000 came from individual and business donors in both Hargeisa and in the disaspora. “We had higher ambitions,” Elmi tells me, “but we had to humble our approach, since the last three years the country has been suffering from a large drought.”

Now the scheme is moving to its second phase: books, computers and printers, plus landscaping the gardens. This will cost another $175,000. “We are also open to donations of books, furniture and technology,” Emli says. “Or even someone with technical expertise who can help up set-up the librarian system instead of a contemporary donation of a cash sum.” The Czech government, in fact, has helped with the latter: it’s not offered financial support, but has offered to spend four weeks training two librarians.  

Inside the library.

On internet forums frequented by the Somali diaspora, a number of people have left comments about the best way to do this. One said he’d “donated all my old science and maths schoolbooks last year”. And then there’s this:

“At least 16 thousand landers get back to home every year, if everyone bring one book our children will have plenty of books to read. But we should make sure to not bring useless books such celebrity biography books or romantic novels. the kids should have plenty of science,maths and vocational books.”

Which is good advice for all of us, really.


Perhaps the pithiest description of the project comes from its Facebook page: “Africa always suffers food shortage, diseases, civil wars, corruption etc. – but the Somaliland people need a modern library to build a better place for the generations to come.”

The building doesn’t look like much: a squat concrete block, one storey-high. But there’s something about the idea of a country coming together like this to build something that’s rather moving. Books are better than sovereignty anyway.

Jonn Elledge is the editor of CityMetric. He is on Twitter as @jonnelledge and also has a Facebook page now for some reason. 

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