Heavy downpours and persistent rain risk knocking out hospitals and causing floods with sewage discharges and bacterial diseases as a result.
To avoid such nightmare situations, Sweden’s major cities are now planning to divert large amounts of water.
A heavy downpour in July 2013 filled the floors in the corridors to the operating theaters at Ryhov County Hospital in Jönköping and came close to knocking out the hospital’s power plant. Waste water in Östersund is believed to have contributed to over 20,000 people becoming ill after an outbreak of the parasite cryptosporidium in the municipal drinking water a couple of years earlier. These are just a couple of the consequences that major floods and polluted sewage have caused in Sweden in recent decades.
Will divert water
The floods and downpours of the past few days have once again raised the question of the cities’ ability to handle heavy water flows.
Larger cities, such as Stockholm, Gothenburg and Malmö, are now planning to divert the torrential water masses to places where the water can be collected without damaging hospitals, roads or embankments, Erik Karlsson, strategist for pipeline networks and asset management at Svenskt Vatten, tells TT.
While, for example, Copenhagen has already come a long way and realized this type of urban planning, the larger cities in Sweden are only at the beginning of their work, according to Erik Karlsson.
– They have recently finished their computer simulations of such solutions and will now start putting the plans into action.
Removes downpipes
Since a city is largely covered by private land, in order to make room for the water, the city must cooperate with the property owners.
In Malmö and Lund, the regional VA company VA Syd as the carrot has pledged a compensation of around SEK 2,500 for each downpipe that a private property owner, given certain conditions, removes, says Erik Karlsson.
When the water comes down through the downpipes, there is too much water, which suddenly puts a strain on the network when it rains a lot.
– But if the water lands directly on the ground, it can be directed away to better suited places or collected by a lawn or park, he says.
So far, a thousand property owners in Malmö have taken up the offer linked to removing the downpipes, according to Kristina Hall, VA strategist at VA Syd.
The prerequisite, however, is that the property owner can manage the water on their own property in the form of, for example, rainwater barrels or on green areas, she says.
To take care of larger water flows, on the other hand, larger solutions are required. In Malmö, the municipality has, among other things, sunk parts of Söderkullaparken in order to handle large amounts of surface water.
– If there is a lot of water, it stays there and does not flood into nearby areas, says Kristina Hall.
Lowers the Humlegården
In Stockholm, they will try to direct water flows to Rålambshovsparken and delay them there.
– There are also plans to sink parts of Humlegården in Stockholm to collect the water, says Erik Karlsson.
Even in Gothenburg, districts are designed with the aim of delaying water flows so that they do not damage properties.
Even though more and more municipalities have become ambitious in their work with preparedness against flooding, most conduit networks in Sweden’s municipalities are not adapted to handle heavy rainfall, says Erik Karlsson.
– Many billions are needed to improve capacity. Several municipalities may find it difficult to get advice, he says.
FACT Floods
In Sweden, floods occur more or less regularly. The most common types of flooding are:
Flooding along lakes and streams that occurs during long periods of heavy rainfall or snowmelt.
Coastal flooding caused by rising sea levels, which often occur in conjunction with storms or other weather phenomena.
Flooding as a result of extreme downpours that fall over a small geographical area in a short time.
Source: The Authority for Community Protection and Preparedness.
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