The Nokia water supply contamination occurred from November 28 to 29, 2007, when a large part of the

water Water (chemical formula ) is an inorganic, transparent, tasteless, odorless, and nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living organisms (in which it acts as a ...

supply in

Nokia Nokia Corporation (natively Nokia Oyj, referred to as Nokia) is a Finnish multinational corporation, multinational telecommunications industry, telecommunications, technology company, information technology, and consumer electronics corporatio ...

Finland Finland ( fi, Suomi ; sv, Finland ), officially the Republic of Finland (; ), is a Nordic country in Northern Europe. It shares land borders with Sweden to the northwest, Norway to the north, and Russia to the east, with the Gulf of B ...

, was contaminated with treated sewage water. The contamination affected an area with some 12,000 inhabitants and caused an epidemic of thousands of cases of diarrhea and vomiting primarily due to

Norovirus Norovirus, sometimes referred to as the winter vomiting disease, is the most common cause of gastroenteritis. Infection is characterized by non-bloody diarrhea, vomiting, and stomach pain. Fever or headaches may also occur. Symptoms usually deve ...

and

Campylobacter ''Campylobacter'' (meaning "curved bacteria") is a genus of Gram-negative bacteria. ''Campylobacter'' typically appear comma- or s-shaped, and are motile. Some ''Campylobacter'' species can infect humans, sometimes causing campylobacteriosis, a d ...

infections. Hundreds of inhabitants were hospitalised, and the town was forced to temporarily forbid all use of tap water. The cause of the contamination was revealed to be a combination of different events. A maintenance man in the Nokia waterworks had opened a

valve A valve is a device or natural object that regulates, directs or controls the flow of a fluid (gases, liquids, fluidized solids, or slurries) by opening, closing, or partially obstructing various passageways. Valves are technically fittings ...

between tap water and sewage water pipes to let some tap water flush out the sewage pipe. The valve had been previously installed against regulations. Because of pressure differences, the water flowed in the opposite direction, contaminating the tap water. At the same time, maintenance work was being carried out at another site, so the first calls from people complaining about the water were not taken seriously because they were thought to be connected with that event. It took two days until an official warning was given that the water was contaminated and until bottled water deliveries were started.Onnettomuustutkintakeskus: Tiedote Nokian vesiepidemian alkutapahtumista
May 21, 2008

Background

There was a poorly designed installation in the Kullaanvuori water treatment facility. A drinking water pipe was connected to a wastewater pipe for the purpose of flushing the wastewater pipe. Such an installation is illegal, and for good reason; if the water pressure in the drinking water pipe is too low, backflow occurs. This is what happened in this event. A maintenance worker accidentally opened the valve, and wastewater flowed into the drinking water supply for two days. The contamination was actually detected, but the company decided to ignore it, assuming it was a transient pulse caused by the repairs.

Identified bacteria and viruses

As of December 15, 2007: *

Escherichia coli ''Escherichia coli'' (),Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. also known as ''E. coli'' (), is a Gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus ''Escher ...

Nokian kaupunki: Nokian terveyskeskuksen yhteenveto vesiepidemiasta tähän mennessä sekä arvioita lähiviikoista
/ref> *

Salmonella ''Salmonella'' is a genus of rod-shaped (bacillus) Gram-negative bacteria of the family Enterobacteriaceae. The two species of ''Salmonella'' are ''Salmonella enterica'' and ''Salmonella bongori''. ''S. enterica'' is the type species and is fur ...

Clostridium difficile ''Clostridioides difficile'' (syn. ''Clostridium difficile'') is a bacterium that is well known for causing serious diarrheal infections, and may also cause colon cancer. Also known as ''C. difficile'', or ''C. diff'' (), is Gram-positive spec ...

Rotavirus ''Rotavirus'' is a genus of double-stranded RNA viruses in the family ''Reoviridae''. Rotaviruses are the most common cause of diarrhoeal disease among infants and young children. Nearly every child in the world is infected with a rotavirus a ...

Adenovirus Adenoviruses (members of the family ''Adenoviridae'') are medium-sized (90–100 nm), nonenveloped (without an outer lipid bilayer) viruses with an icosahedral nucleocapsid containing a double-stranded DNA genome. Their name derives from the ...

References

External links

* HS
Contaminated water crisis continues in Nokia
(Dec 7, 2007) * HS
Nokia water crisis eases
(Dec 10) *

YLE Yleisradio Oy (Finnish, literally "General Radio Ltd." or "General Broadcast Ltd."; abbr. Yle ; sv, Rundradion Ab, italics=no), translated to English as the Finnish Broadcasting Company, is Finland's national public broadcasting company, founde ...

Call For Accountability In Nokia Water Contamination
(Dec 12) * YLE

(Dec 15) * HS
Investigation underway into deaths possibly linked to tainted Nokia city water
(Dec 19) {{coord missing, Finland 2007 in Finland Water supply contamination Health disasters in Finland