Challenging projects

Closure of untreated wastewater discharges

As a result of the Northern Tunnel Collector Project, 98.4 % of wastewater has been treated in St. Petersburg since 10 October 2013.

 In December 2014, Vodokanal of St. Petersburg closed:

 -       9 direct discharges of Petrovsky Stadium which previously discharged thousands cubic meters of untreated wastewater to the Neva River daily. This wastewater is currently transported to the Northern Wastewater Treatment Plant and undergoes full treatment cycle.

-       19 direct wastewater discharges along Petrogradskaya Embankment. Of these, 17 were operated and maintained by Vodokanal (three combined sewerage discharges with total flow of 4 thousand cubic meters per day and 14 runoff discharges with average flow of 23 cubic meters per day), and 2 more belonged to industrial enterprises. Wastewater from direct discharges is rechanneled through the Northern Tunnel Collector to the Northern Wastewater Treatment Plant, where it undergoes a full treatment cycle.

In 2015, 5 direct wastewater discharges were closed in Admiralteysky district under the reconstruction of the sewerage networks from Novo-Admiralteysky Canal to Truda Square, and 1 direct wastewater discharge was closed as part of the construction of the sewerage network in Repina Square. 6 direct wastewater discharges with total flow of 1.0 thousand cubic meters/day were closed in 2015.

In 2016, 15 direct wastewater discharges with total flow of 366 cubic meters per day were closed. The company stopped the direct discharge of untreated wastewater to the following water bodies: Bolshaya Neva, Srednaya Nevka, Malaya Nevka, Neva Bay, Okhta (1 direct discharge on Shaumyan Ave.), Chukhonka, and Chernaya Rechka.

In 2017, works on the reconstruction of the stormwater sewerage system under Murinsky Park upgrading were completed and allowed to re-channel 7 direct stormwater discharges through the sewerage tunnel to the Northern Wastewater Treatment Plant.

In 2017, within the framework of closure of untreated discharges into water bodies, 11 untreated discharges (9 stormwater discharges and 2 stormwater overflows) with total flow of 28.5 thousand cubic meters/day were closed.

In 2018, 11 untreated wastewater discharges with total flow of 9.1 thousand cubic meters / day were closed. 7 stormwater discharges were closed under the upgrading of Murinsky Stream. 3 stormwater overflows were closed under the reconstruction of sewerage networks along Primorsky Ave. One untreated wastewater discharge of the combined sewerage system was closed in the town of Lomonosov, thus stopping the discharge of wastewater to the Neva Bay of the Gulf of Finland.

As a result of all the work on the closure of the untreated wastewater discharges for the period 2014-2018, the percentage of household wastewater treatment reached 98.6%.

In early December 2019, the percentage of household wastewater treatment reached 99%.

In 2020, it is planned to complete the 1st stage of construction of the Okhta Tunnel, which will enable to close the untreated wastewater discharges with total volume of about 11 million cubic meters in the Okhta River area and will facilitate the development of the adjacent territories.

 

Reconstruction of the wastewater treatment plants

Vodokanal is reconstructing the Central WWTP and the Northern WWTP in order to increase wastewater treatment efficiency and stabilize the nutrients removal process.

 In next years, comprehensive rehabilitation of Kolpino WWTP and Pontonny WWTP as well as modernization of Zelenogorsk WWTP will be implemented.

 Construction of a new wastewater treatment plant in the settlement of Molodezhnoe is underway. For the first time in St. Petersburg, a new technology of membrane bioreactors will be introduced at this plant. The project of new WWTP in Molodezhnoe comprises construction of the main pumping station, treatment facilities (including mechanical and biological treatment), sludge treatment facilities, chemical facilities and gas treatment facilities. The new WWTP capacity will be 2,500 cubic meters per day and will ensure treatment of wastewater from three settlements - Molodezhnoe, Serovo and Smolyachkovo.

In 2017, Vodokanal completed the first stage of reconstruction of the Northern Wastewater Treatment Plant, as a result, the reduced capacity of the plant increased from 690 to 800 thousand m3/day.

In 2018, Vodokanal completed the construction of a new wastewater treatment plant in the settlement of Molodezhnoye and the modernization of the first-stage aeration tanks with the introduction of deep nutrients removal process at the Central Wastewater Treatment Plant. Also the company launched the 2nd stage of reconstruction of mechanical and biological treatment facilities at the Northern Wastewater Treatment Plant. The implementation of these projects is targeted to the reduction of the negative impact on the environment and achievement of the stable wastewater treatment quality.

Vodokanal started the second stage of reconstruction of the Northern Wastewater Treatment Plant.


Recycling of wastewater sludge stored at the landfills

Before the commissioning of the sludge incineration plants, wastewater sludge was disposed to the landfills. Vodokanal introduces the geo-tube method to treat and recycle sludge stored at the landfills. Sludge is fed into the geo-tubes (containers made of polymer filter cloth) after being treated with special chemicals. The method presupposes filtration of sludge liquid phase through the walls of geo-tubes located on specially arranged drainage platform. The result of such treatment is the production of a harmless substrate, which is odor free and may be used for manufacturing man-made soils.


Improvement of the sewerage system reliability

In order to reduce the negative impact on the city water bodies, in the coming years Vodokanal will continue the construction and reconstruction of sewerage networks and collectors for rechanneling the untreated wastewater discharges:

  • Construction of the Okhta collector
  • Construction of sewerage networks from the settlements of Reshetnikovo and Krasavitsa to the town of Zelenogorsk
  • Closure of untreated wastewater discharges in Petrogradsky district, 15 untreated wastewater discharges along the Karpovka River embankment
  • Reconstruction of sewerage network from Martyshkino sewerage pumping station to Petrodvorets sewerage pumping station, which will allow rechanneling sewerage of the town of Lomonosov into the combined sewerage system, since for now such sewerage is discharged without any treatment.

In order to improve the reliability and environmental safety of the sewerage system, construction and reconstruction of sewerage networks and collectors will continue:

  • Construction of a connecting pipe from 1/27 shaft of the tunnel collector at 33 Obukhov Ave. to the shaft of the Northern Tunnel Collector
  • Reconstruction of tunnel sewers along the Kryukov Canal and Moyka River embankments
  • Reconstruction of the influent collector to Zelenogorsk WWTP
  • Design works for the construction of the 3d stage of the Vyborgsky back-up tunnel sewer in the area of Muzhestvo Square.

In order to provide access to the centralized wastewater disposal services, the design and construction of sewerage systems in settlements is carried out. The company will start the construction of sewerage networks in Gorelovo of Krasnoselsky district (stage 1), Lisiy Nos of Primorsky district, Toriki of Krasnoselsky district, Novoselky of Pushkinsky district of St. Petersburg. Design works will be completed and construction will begin in Gorelovo of Krasnoselsky district (stage 2), in the settlements of Petro-Slavyanka, Pontonny and Saperny of Kolpinsky district, in the town of Pavlovsk of Pushkinsky district, Kronstadt of Petrodvorets district of St. Petersburg.