Collaboration to preserve the Gulf of Finland
The research vessels returned from their August tours around the Baltic Sea with some alarming news about the condition of the Gulf of Finland. Luckily, joined efforts to reduce discharges are underway.
No matter the weather, the crew of the research vessel Muikku study the water, floor, fauna and flora of the Baltic Sea. Photo: Seppo Knuuttila / SYKE.
The eastermost arm of the Baltic Sea on the cost of Finland, Russia, and Estonia is called the Gulf of Finland. The Russian city of St. Petersburg is located at the very tip of the Gulf, and the Estonian and Finnish capitals Tallinn and Helsinki are situated opposite to each other by the gulf.
According to recent research conducted with Finnish Environment Institute’s research vessels Aranda and Muikku, the condition of Gulf of Finland has deteriorated, after having developed favourably over the last three years.
In deep water areas of the Gulf of Finland, poorer oxygen conditions and higher nutrient concentrations are resulting from the inflow of deep water from the Central Baltic Sea into the Gulf of Finland. This is due to the high pressure weather conditions prevailing for long periods last winter and this summer.
Modern wastewater treatment to reduce phosphorus
Improving the condition of the gulf, and the Baltic Sea as a whole, requires joint efforts from the coastal countries. One of the ongoing projects is the modernization of ten small wastewater treatment plants in St. Petersburg.
The goal of this joint project is to upgrade the treatment of wastewater at small and medium-sized plants by, among other things, installing modern equipment, which will enable the chemical removal of phosphorus. Currently, almost 85 per cent of St. Petersburg’s wastewater is treated. The percentage will be 94 when the modernization is completed.
The phosphorus discharges have been reduced in the bigger wastewater treatment plants by 50 % during the last ten years.
The current project is financed by the Nordic Environment Finance Corporation (NEFCO) and the Finnish Ministry of the Environment. The other financiers are the Northern Dimension Environmental Programme (NDEP) and the local waterworks company Vodokanal, which is also responsible for implementing the project.
When ready, the modernization is expected to reduce discharges of phosphorus into the Neva River and the Gulf of Finland by some 40 tonnes per year – a figure equivalent to the discharge of untreated wastewater by more than 53,000 people per year.
Improvements over the decades
According to the Finnish Environment Institute, improved wastewater treatment in St. Petersburg will drastically improve water quality, promote biodiversity and reduce the spread and proliferation of toxic algae (cyanobacteria) in the Gulf of Finland.
“This project is intended to solve all the nutrient discharge problems emanating from the City of St. Petersburg, for once and all, and after the modernization process, the city will comply with all the recommendations laid out by Helsinki Commission [Baltic Marine Environment Protection Commission],” says NEFCO’s Vice President, Kari Homanen.
St. Petersburg’s wastewater treatment system has been substantially improved and upgraded during the last ten years. The first tests on improving biological phosphorus removal, which were supported by the Finnish Ministry of the Environment, were carried out in the area during the mid 1990’s. In 2000, this cooperation was extended to the chemical removal of phosphorus.
Elisa Lautala works as web editor for University of Helsinki's Faculty of Science. Elisa likes all kinds of cultural events, good books, warm weather, and aqua-jogging.