Water quality of Finland's sea areas deteriorates sharply

Large southern lakes still lack thick winter ice cover

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The water quality of Finland's sea areas has deteriorated considerably from the mid-1990s. Within just a few years there has been a sharp decline in sea areas where the water quality was ranked as good, and up to 20% of coastal waters are now classified as merely "satisfactory".
      Much of the trend is due to eutrophication in the Gulf of Finland, the southwest archipelago, and the areas near the mouths of rivers in the northern part of the Gulf of Bothnia.
     
Experts say that the situation is most alarming in the Gulf of Finland, where the water quality of shallow bays and river deltas is ranked as "fair".
      Although emissions into the gulf have decreased, the eutrophication process has not yet slowed down. One indication of this is the increase in summertime blooms of blue-green algae.
      Lea Kauppi, director-general of the Finnish Environment Institute, says that emissions are still too great for the gulf to handle, and that sewage from the city of St. Petersburg is not the only culprit.
      "Agriculture is a very significant factor in domestic emissions", she emphasises, adding that it accounts for more than half of the emissions of phosphorous and nitrogen in the Baltic Sea.
     
The state of Finland's lakes has remained mostly unchanged from the mid-1990s, according to the new classification system. The record for Finnish rivers has been mixed, with some showing improvement and others exhibiting deterioration.
      The quality classification, published on Tuesday, is based on information from 2000 - 2003, and indicates that Finland's surface waters are mostly in good condition.
      Water quality was ranked as excellent or good in 80% of Finland's lakes, 73% of its sea areas, and 43% of its rivers. The corresponding figures five years ago were 80% for lakes, 90% for sea areas, and 39% for rivers.
      Water quality was fair to poor in five percent of lakes, one percent of coastal sea areas, and one third of river areas. The quality of river water is worse than that of lakes almost without exception, because both human habitation and agriculture tend to concentrate along rivers.
     
The mild winter so far has left the ice on Finnish lakes thinner than usual.
      A few larger lakes in Southern Finland have no ice cover at all.
      The Saimaa waterway, the open areas of Lake Päijänne, and Lake Pyhäjärvi in the southwest have so little ice that it was not possible to measure the thickness on January 10th.
      The ice on a lake must be at least four centimetres thick in all parts of a lake to support the weight of those making the measurements.


Previously in HS International Edition:
  Salmon are vanishing from the Gulf of Finland (21.6.2004)
  Experts fear bad blue-green algae situation in Gulf of Finland this summer (10.5.2004)
  Water quality in Gulf of Finland deteriorates alarmingly from last year (11.8.2003)

Links:
  Weekend winter storm may improve water quality in Gulf of Finland (12.1.2005)

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