Water pollution Water pollution

The Baikal Russian reserves of water are the biggest in the world second only to Brazil. The largest repository of fresh water in Russia is Lake Baikal. Lake Baikal contains 1 / 5 of all freshwater in the world. Anthropological impact on the Baikal has markedly increased since 1950. Industrial and civil buildings have grown, the population has increased, new cities and settlements have appeared, more land has been plowed, and agriculture used lots of chemicals. Increased logging on the rivers has led to water pollution. There are a lot of tourists there, and pulp and paper mills have been built in the area. On the north bank Baikal-Amur Railway has been built.

Pollution of Lake Baikal Measures have been taken to prevent the threat of pollution. Logging was stopped on the rivers and as a result wood transportation on Lake Baikal reduced. Many industrial enterprises have been converted to a closed water system. However, these measures are not enough. There is still a threat of pollution. Today the biggest threat to the lake pollution comes from two sources - the city of Ulan-Ude and Baikal Pulp and Paper Plant. When factories were built, there was a dramatic public protest against their construction, motivated by the inevitable contamination of unique pure waters of the lake, inhabited by unusual living creatures, which can be found only there. However, public protest was in vain. Factories were built. Baikal is becoming contaminated. Pollutants have an impact on its plant and animal life and reduced the water quality of Lake Baikal. Knowing this led us to the conclusion that that the Baikal pulp and paper mills must be replaced by new mills using new water treatment systems. (We need Baikal alive)

Neva river There are at least three versions of the origin of the name Neva: from the ancient Finnish name of Lake Ladoga (Finnish: nevo meaning sea), from Finnish: neva (short from Finnish: Nevajoki, Nevajärvi) meaning swamp, or from the Swedish language: ny – new river. Modern names for the distributaries of the river delta were settled only by the end of the 18th century.

Pollution of the Neva River The Federal Service for Hydrometeorology and Environmental Monitoring of Russia classifies Neva as a "heavily polluted" river. The main pollutants are copper, zinc, manganese, nitrates and nitrogen. The dirty tributaries of the Neva are the Mga, the Slavyanka, the Ohta and the Chernaya. Hundreds of factories pour wastewaters into the Neva within St. Petersburg and petroleum is regularly transported along the river. The annual income of pollutants is 80,000 tonnes, and the heaviest polluters are Power-and-heating Plant 2, the plant "Plastpolymer" and "Obukhov State Plant". The biggest polluters in Leningrad region are the cities of Shlisselburg, Kirovsk and Otradnoye, as well as the Kirov TPS. More than 40 oil spills are registered on the river every year. In 2008, the Federal Service of St.-Petersburg announced that no beach of the Neva is fit for swimming.

Vodokanal Cleaning of waste water in St. Petersburg was started in 1979 and by 1997 about 74% of wastewater was purified. This number rose to 85% in 2005, to 92% by 2008, and it is expected to reach 100% by 2011 with the completion of the expansion of the main sewerage plant.

Water treatment technologies water ammonation (ammonium sulfate is used), water disinfection (sodium hypochlorite is used), coagulation of pollutants (aluminium sulfate is used), flocculation (cationic flocculant is used) sand filtration in contact clarifiers (one-stage treatment scheme) sedimentation and sand filtration in rapid filters (two-stage treatment scheme) Disinfection by UV exposure.

Modern technology Since 2007, Vodokanal applies a unique two-stage process of overall water disinfection at St.-Petersburg waterworks. This process is based on a highly effective but safe chemical – sodium hypochlorite (chemical method) and UV water treatment (physical method). Such combination enables us to fully guarantee epidemiological safety of water supply in St.-Petersburg, and total compliance of microbiological indicators of water quality with the current norms. St.-Petersburg is the first megalopolis to treat all potable water with ultraviolet and to use no liquid chlorine for potable water disinfection.

Good-bye chlorine! The official ceremony of discarding the last chlorine container was held at the Northern Waterworks on 26 June, 2009. Chlorine (a hazardous substance to store and transport) gave place to safe sodium hypochlorite. Two plants for production of low-concentrated sodium hypochlorite are in operation in St.-Petersburg – at the Southern Waterworks (since 2006) and at the Northern Waterworks (since 2008).

Biomonitoring Another technology used by Vodokanal for over two years is a powdered activated carbon (PAC) dosing system which ensures removal of odors and oil products. Vodokanal is proud of its unique system of water quality biomonitoring - diagnostics of the functional status of crayfish and fish. The method developed by the Russian Academy of Sciences’ Environmental Safety Research Institute consists in measuring the local crayfish cardiorythm and analysing the behavior of fish. If the water from the Neva contains toxic substances, the heart rate of crayfish increases, and the behavior of fish changes significantly. Now, the biomonitoring system is used at all waterworks in the city. The “staff” of the Main Waterworks includes 12 crayfish. Their working schedule: two days in the aquarium under supervision, then four days of rest and active eating. Vodokanal employs male crawfish only.

Thanks for your attention!!!