Protection of the Baltic Sea

One of St. Petersburg Vodokanal priority tasks is to mitigate negative impact of the big city on the environment, thus improving the environmental conditions in the Baltic Sea Region.   

Within the commitments undertaken by the Russian Federation to fulfil the Helsinki Convention on the Protection of the Marine Environment of the Baltic Sea (Helsinki Convention), St. Petersburg Vodokanal implements large-scale activities targeted to the reduction of untreated wastewater discharges and removal of nutrients (nitrogen and phosphorus) from wastewater.    

The Convention on the Protection of the Marine Environment of the Baltic Sea was signed by all Baltic States in 1974. The Convention for the first time dealt with all polluters located in the catchment area of the Baltic Sea. After political changes stemmed from the collapse of the USSR, establishment of new independent states, unification of GDR and FDR, as well as development of the international environmental law, the new Helsinki Convention was signed in 1992 by the states located along the coast of the Baltic Sea and by the European Community. It was put into effect upon the ratification on January 17, 2000. The Russian Federation approved the 1992 Helsinki Convention in October 1998. 

 The main purpose of the Convention is to protect the marine environment of the Baltic Sea, restore and preserve the environmental balance in the Baltic Sea region and ensure sustainable use of natural resources.

 Member-countries committed to take all necessary legislative, administrative and other measures to prevent the Baltic Sea pollution and eliminate the existing pollution sources for the purpose of the Baltic Sea ecosystem rehabilitation.

Prevention of the Baltic Sea pollution with nitrogen and phosphorus is a pressing problem for all Baltic Sea states.

The governing body of the Convention is the Helsinki Commission, the Baltic Marine Environment Protection Commission (HELCOM), which in particular issues recommendations (regulations) for municipal wastewater treatment.  

In the 1990s, for the first time ever, the Helsinki Commission adopted uniform parameters for nutrients (nitrogen and phosphorus) removal for all Baltic Sea states. These parameters become more stringent all the time.

New recommendations for municipal wastewater treatment adopted on November 15, 2007 set forth much more stringent requirements to wastewater treatment. Discharges of effluent into water bodies had to meet the following parameters: total nitrogen -10 mg/l, total phosphorus – 0.5 mg/l.

SUE “Vodokanal of St. Petersburg” all-time improves biological wastewater treatment technologies, in particular, to fulfil stringent requirements to phosphorus compounds removal.   

To meet new requirements and stabilize nutrient removal process at wastewater treatment plants of St. Petersburg, as long as in 2005, the enhanced biological treatment and chemical phosphorus precipitation were introduced at wastewater treatment plants.

 In June 2011, St. Petersburg fully met new recommendations of the Helsinki Commission: content of phosphorus in the total municipal wastewater discharge did not exceed 0.5 mg/l.

The President of Finland Tarja Halonen participated in the official ceremony marking this event. 

 By now, the enhanced nutrient removal processes have been implemented at all wastewater treatment plants of St. Petersburg.

 Achievement of stable treatment parameters is facilitated by continual reconstruction of existing facilities and construction of new ones.

In 2017, the 1st stage reconstruction of the largest treatment facilities in our city - the Northern Wastewater Treatment Plant – was finalized.

Over the period 2012-2017, 8 primary sedimentation tanks were reconstructed, 2 new raw sludge pumping stations were built, raw sludge pre-fermentation technology was introduced, a new return and excess sludge pumping station was built, 5 sections of one aeration tank were reconstructed with the use of the enhanced nitrogen and phosphorus removal technology, and 6 secondary sedimentation tanks were reconstructed. The adjusted capacity of the Northern WWTP after the completion of the 1st stage was 800,000 cubic meters per day. Since 2018, the 2nd stage of the reconstruction has begun, the completion is scheduled for 2020. According to the results of the two-staged reconstruction, the capacity will reach 1 million cubic meters per day, which will enable to develop the territories in the northern part of the city, connect the facilities of the Leningrad Region and, at the same time, ensure stable efficiency of wastewater treatment, which is necessary for complying with the legislation requirements of the Russian Federation and the HELCOM recommendations.

 In 2018, the construction of a new wastewater treatment plant is Molodezhnoe settlement was completed.

The technology of membrane bioreactors was introduced at this WWTP for the first time ever in St. Petersburg. The capacity of the new plant is 2,500 cubic meters per day and ensures the treatment of sewerage from three settlements – Molodezhnoe, Serovo and Smolyachkovo.

 An important event related to the fulfilment of HELCOM Recommendations is the completion of the Northern Tunnel Collector.