UZOS South-West Wastewater Treatment Plant, St. Petersburg, Russia

Completing the South-West Wastewater Treatment Plant (UZOS), scheduled for 2005, has been designated the single most important water protection project on the Baltic. Begun in the days of the former Soviet Union, and postponed due to lack of funds, the current project brings finance from a variety of Western European and Scandinavian sources - including, for the first time ever, the European Investment Bank - to the Russian Federation to finish the job.

The plant will have an average daily capacity of 330,000m³ and treat the wastewater from 720,000 of St Petersburg's 5 million inhabitants. In addition to completion of the wastewater treatment plant and the effluent discharge pipes, which use many of the existing, unfinished structures, associated works include the construction of a sludge incineration plant and upgrades and extensions to the city's sewer system. The incoming wastewater flow will ultimately be treated in three stages - mechanical, biological and chemical - providing an eventual effluent which will meet the requirements established by Helcom, the Helsinki Commission for Baltic Sea water.

Ownership of the overall project lies with a special purpose vehicle, Nordvod, which was established as a limited liability company in Russia. It is owned by the St. Petersburg water utility, Vodokanal, the Nordic Environment Finance Corporation (NEFCO) and a consortium comprising YIT, Skanska and NCC. The building work is being done by SWTP Construction, which is also a YIT / Skanska / NCC consortium.

Financial agreement on the project was signed in December 2002 and construction work began on 21 March 2003. Completion is scheduled for August 2005.

The overall project cost approaches €180 million.

WASTEWATER TREATMENT BACKGROUND

Construction originally began in 1987 but a lack of finance led to a severe curtailment of work by the middle of 1992 and its full cessation three years later, when around 40% of the plant had been completed.

Continuing economic development and population growth, coupled with insufficient wastewater treatment capacity, led to increasing quantities of untreated sewage - amounting to between 25% and 30% of St. Petersburg's wastewater - being discharged into the Neva river. This pollution of the Gulf of Finland was deeply unpopular both with the city authorities and the neighbouring Baltic states, leading to a frank and comprehensive discussion of the problem with officials from St. Petersburg, Stockholm and Helsinki in June 1999. In the same year, at the second meeting of the EU-Russia Energy, Environment and Nuclear Subcommittee, a number of potential western European sources of finance were identified to fund a completion project. By the end of 1999, a pre-investment appraisal had been made.

In financial terms, this scheme has achieved many firsts. Aside of being the first ever European Investment Bank loan to the Russian Federation, it is the first project in Russia to have used combined private, budget and donor financing. It also has the distinction of being the first project to be implemented under the framework of Northern Dimension Environmental Partnership (NDEP), an international programme, initiated by the EU, countries around the Baltic and international financial institutes.

COMPLETING THE WASTEWATER TREATMENT PLANT

The main elements of the completion project consist of constructing four new equalizing tanks, a by-pass pipeline, two new secondary sedimentation tanks, new sludge thickener tanks and a number of new buildings, including two gatehouses. In addition, the existing site wall requires finishing, associated pipes and cables will be required and, although much of the existing plant is to be incorporated, there will be some partial demolition work. Finally, the site will be landscaped and planted and the existing site fence rehabilitated and completed.

The construction of the effluent discharge pipeline to the Gulf of Finland comprises two elements. The onshore part, from the plant to the outlet chamber at the seashore, consists of two underground concrete gravity sewers, extending to over 4km in total. The submarine section, from the outlet chamber to the discharge point at sea, is made up of two steel pipes, with a total length slightly under 5km.

As the final part of the effort to improve St. Petersburg's sanitation system and reduce Baltic sea pollution, a sludge incineration plant is being constructed. The decision to install one at the UZOS facility was taken in the light of the successful performance of similar plants at two of St Petersburg's other WWTPs. The system being built will be able to process approximately 68t/d of dry solid. It incorporates state-of-the-art technologies including fluidised bed furnaces and flue gas purification filters, in full compliance with EU environmental standards. The incineration plant will be operational by the end of 2005.

The incinerator's output is expected to be used as building materials, initially in the road construction anticipated in the south-west of the city as a result of house building made possible by the extra capacity of the completed WWTP. According to estimates, the finished plant could adequately service more than 4 million m² of additional residential development.

When completed, the improvement of St. Petersburg's wastewater treatment will lead to a significant reduction in the amount of the major pollutants discharged annually to the Gulf of Finland, particularly in terms of suspended solids, phosphorus, nitrogen and organics. In addition, a 40% to 60% reduction in heavy metal salts has also been predicted.

KEY PLAYERS

The completion project is sponsored by the City of St Petersburg and supported by the Russian Federation. Nordvod, the Russian ownership company, is 41% owned by the NCC / Skanska / YIT consortium, 41% by Vodokanal and 18% by NEFCO. SWTP Construction is the main contractor and Ecovod has been set up as the operating company, which will be responsible for the plant operation, management and maintenance for 12 years after completion.

Vesa Ekholm and Antero Syrjänen were the architects and structural design was done by Insinööritoimisto Vahanen. Plancenter were responsible for the mechanical, site works and process design, with Ettelplan Oy responsible for the electronics, control and automation. The main plant designer was SUE Lengiproinzhproect.

A total of 14 different financing sources from Western Europe and Scandinavia were involved in funding the project, providing a variety of bank loans, government grants and donations. The bodies involved include the European Bank for Reconstruction and Development, the Nordic Investment Bank, the European Investment Bank, the Northern Dimension Environmental Partnership, the Finnish Ministry of the Environment, NEFCO, the Swedish International Development Agency, the Swedfund International AB, Tacis and the Finnish Fund for Industrial Cooperation.

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