Czajka sewage plant to finish early

Construction of the Czajka large-scale sewage treatment plant to the north-east of Warsaw, Poland is scheduled to finish in December 2010, after a two-year construction period.

With a cleaning capacity of almost 450000 m3 per day it is designed to service 2 million people and will be the largest waste-water facility in the country.

To complete the project in such a short time, main contractor Warbud and formwork manufacturer Peri developed a cost-effective and comprehensive formwork and scaffolding concept that "fulfilled all requirements regarding the best-possible concrete surfaces, short construction period and a high level of on-site safety."

Covering 600000 m2 the Czajka site placed "very high demands on site personnel and the formwork systems being used", according to a Peri spokesman; a total of 120 complex individual structures were designed and built.

Depending on the purification stage of the sewage, the tanks vary in both form and height, but in spite of the tight construction schedule, Peri has been able to supply the large quantity of materials required to the site on time. While the small number of different individual components ensured construction could be accelerated.

As a result, around 50000 m2 of straight walls and 30000 m2 of circular wall surfaces have been constructed "efficiently".

For forming the 8 to 11 m high, 250 to 750 mm thick, walls Warbud used Peri's Trio, Vario and Rundflex wall formwork systems and Peri Up scaffolding system, which offered a customised solution, maximum safety and fast shuttering times thanks to the formwork being moved as a complete unit from cycle to cycle.

A well-rounded solution

Construction of sewage treatment plants involves the forming of reinforced concrete walls with a range of different tank diameters. Peri's Rundflex formwork system is ideal as it can be adjusted quickly and easily to match the required radius.

The self-cleaning hexagonal thread of the spindles provides continuous fast adjustment. While the extension splice means panels remain securely connected to each other even at heights of 8 m.

Horizontal connections use Peri's BFD alignment coupler, which bridges infill areas of up to 100 mm thick with only one connection part so the number of individual components is reduced, helping save time and money.

Environmental protection - a sector with a future

Poland's government is currently constructing over 1000 waste-water treatment plants. These are needed to fulfill European standards that take effect in 2015. With a price tag of over € 500 million, Czajka is not only the largest sewage facility in the country, but it is also considered one of the most important environmental protection measures in Europe.

The clients are the municipal water and sewage works of Warsaw, while construction and construction management is by an international consortium consisting of Veolia Water System, Poland; Veolia subsidiary Krüger, Denmark; OTV, France; WTE Wassertechnik, Germany, under the supervision of the Warbud.