St. Petersburg sharply reducing phosphorous emissions into Gulf of Finland

Algae growth should decline, challenges remain for Baltic Sea

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St Petersburg, a major Russian metropolis at the eastern end of the Gulf of Finland, is significantly reducing its emissions of nutrients into the Baltic. A new sewer tunnel and the improvement of waste water treatment are reducing the phosphorous load on the Gulf of Finland to a third. The changes are expected to reduce the problems caused by blue-green algae.
      Felix V. Karmazinov, Director-General of the Russian city's water utility, says that by 2010 nearly all sewage will be treated. The city plans to spend up to EUR 700 million on new sewage treatment plants and drainage tunnels.
      Currently, the waste water of about 700,000 St. Petersburg residents continues to flow, untreated, into the Gulf of Finland. Along with the human waste, phosphorous and nitrogen also flows into the water, spurring growth of algae.
      Phosphorous is especially harmful, adding considerably to the blue-green algae problem.
     
"During the next ten years, the situation will change dramatically", Karmazinov predicts.
      The first part of the northern sewage tunnel, which has been under construction for 20 years, will be ready in the autumn, and the whole tunnel will be taken into use by 2010.
      Karmazinov says that when the tunnel is finished, 98-99% of the city's waste water will be treated. Now the figure is 85%.
      Also reducing nutrient emissions is the chemical treatment to remove phosphorous, which was launched with Finnish help last autumn. Phosphorous emissions are to be restricted to 0.5 milligrams per litre, a level which is significantly below the EU norms.
     "We are certain that the 0.5 milligramme limit will be achieved by 2010", Karmazinov says.
     At present the city's three large treatment plants contain a milligramme or less of phosphorous per litre of water discharged.
     
At the Finnish Environment Institute, leading researcher Heikki Pitkänen calculates that the changes will lead to a reduction in phosphorous emissions into the Gulf of Finland by about one third.
     Blue-green algae should decline proportionately, if other emissions do not increase.
      "The positive effects will also extend to the Archipelago Sea", he predicts.
     Reducing emissions from St. Petersburg alone will not clean the whole Baltic Sea. The biggest source of algae-feeding emissions into the Baltic is Poland, where nearly half of the residents of the catchment area of the Baltic live.
      Poland has begun massive investments worth more than EUR 10 billion into its sewage networks and treatment plants.
     
In addition to nutrients, St. Petersburg is also responsible for emissions of other hazardous substances, such as heavy metals.
     Greenpeace press secretary Maria Musatova walks cautiously along the shore of the Ohta, a tributary of the Neva. On the banks, a drain about one metre in diameter, gushes greyish-brown water into the river.
     Musatova says that the water comes untreated from 16 factories and ten apartment buildings.
      "The river merges with the Neva about ten kilometres from where drinking water is taken", she says.
      There are more than 370 such drains in St. Petersburg. Many of them are to be merged with the northern sewage tunnel, but Greenpeace expects that toxic emissions from factories will continue.
      "The biggest problem is that companies do not have local treatment stations. The state does not force the companies to build such treatment facilities", says Dmitri Artamonov, director of the St. Petersburg office of Greenpeace.
      Greenpeace has found excessive contents of arsenic and PCB compounds in fish in the area.


Previously in HS International Edition:
  Gulf of Finland has slightly higher oxygen level than last summer (14.8.2007)
  Nearly all St. Petersburg sewage to be treated within five years (7.5.2007)

Links:
  St. Petersburg reduces phosphorous emissions into Gulf of Finland (2.10..2007)

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