Water quality in Gulf of Finland deteriorates alarmingly from last year

The condition of coastal waters in the Gulf of Finland has clearly deteriorated from last year. Scientists on the Muikku, a research vessel of the Finnish Environment Institute (SYKE), have been taking samples in coastal waters during five summers, and most results from this year's two-week voyage are considerably more alarming than last year. Thousands of square kilometres of sea bed in the Gulf of Finland are believed to be completely without oxygen. In addition to the bottom layers, there is a shortage of oxygen in the upper layers of the sea, which also kills life on the sea bed. The amount of nutrients on the bottom has increased many times over in places. At worst the bed of the Gulf of Finland can release an amount of phosphorous equivalent to that contained in the untreated sewage of 16 million people. This internal pollution of the Gulf of Finland is overtaking the impact of emissions from land. According to studies by special researcher Jouni Lehtoranta, an area of oxygen-free sea bed one square kilometre in area can release an amount of phosphorous equivalent to the untreated sewage of 4,000 people. "There are about four thousand of these square kilometres in the Gulf of Finland", Knuuttila says. The city of St. Petersburg, which dumps about one third of its sewage into the Gulf of Finland completely untreated, is one of the main sources of pollution in the Gulf of Finland. However, the bottom of the Gulf of Finland can release an amount of phosphorous in a day that is many times greater than that which is caused by the emissions from St. Petersburg.