Electrical fault threatened to disrupt water supply to a large section of Helsinki on Saturday evening
Fixing the problem took several hours as an emergency system also failed
An electrical fault at a water purification plant threatened to put the taps running dry in a large part of Helsinki on Saturday evening.
The fault was detected at the Helsinki Region Environmental Services Authority’s (HSY) Vanhakaupunki water purification plant shortly after three o’clock on Saturday afternoon. A main breaker fault shut down the pumps that send water to water towers.
The fixing of the fault took until late in the evening. Partial operation of the facility was restored at around 8:30 p.m., when the repair crew managed to switch on the emergency electricity system to supply power to the pumps.
HSY Chief engineer Matti Ropponen explained at around ten o’clock in the evening that the threat of the system running out of water had been averted. The broken relay was ultimately fixed just after midnight.
As late as 20:00 on Saturday evening it still looked like residents in Eastern Helsinki might run out of water, and imminently. The water supply to northern districts of the city was also in danger. All told, the water supply of no less than 200,000 was under fairly acute threat, and warnings were put out over the radio.
Luckily the areas in question did not run out of tap water, for the water towers in Ilmala, Roihuvuori, and Myllypuro had enough water stored in them. HSY also put in efforts to alleviate the situation by running the capital area’s other water purification plants at full capacity.
The fault did not affect the quality of the drinking water, but the pressure fluctuation may have loosened deposits from the pipes. “If the water looks brown, let it run until it becomes clear”, HSY advised the Helsinki residents.
Ropponen describes the threat of a water shortage as a “sum of coincidences”. The pumps have an auxiliary power system, but that, too, failed to kick in when it was required.
According to Ropponen, what took place is highly unlikely to happen again.
“The situation was quite exceptional. Something like this has never happened before. There have been temporary power failures before, but never before has the auxiliary system failed simultaneously.”
The reason for the fault in the auxiliary system is so far unknown. Efforts will be made to look into it today.
It was fortunate that it all happened during the weekend (and at a time when a good many local residents would be away at their summer cottages), when the consumption of water is lower than during the week, Ropponen adds.
In the coming years improvements will be introduced to the Helsinki water system, the purpose of which is to prevent disturbances to the water supply.
By 2015 the capacity of the Vanhakaupunki water purification plant will be nearly doubled. After this the capacity of Helsinki’s other plant in Pitkäkoski will also be enhanced significantly.
The city’s water pipe system will also be improved by adding new lines to it to facilitate the easier transfer of water from one area to another.
Plans have been laid to shut down the capital area’s third water purification plant in Espoo’s Dämman by 2015. In the future, Espoo will receive its drinking water from Helsinki’s Pitkäkoski and Vanhakaupunki units.
There have also been talks of building a third purification plant in Helsinki, but as yet no decisions have been made regarding the matter.
HSY Water Services