Modernising the Water Supply and Wastewater System for the Polish Capital
The project envisaged by the awarding organisation is wide in scope, so the investment programme was split into three main areas:
- A distribution system for the Południe wastewater treatment plant (Oczyszczalni Ścieków Południe);
- Improvement of water quality in Warsaw;
- Water supply and wastewater discharge in Warsaw, including the extension and modernisation of the Czajka wastewater treatment plant and development of a central system to manage the combined wastewater network and reservoir located at the plant.
The scope of CDM Smith’s involvement included drafting a concept design for the treatment plant and wastewater system, preinvestment analysis, project and tender documentation to construct a central system to manage the combined wastewater network, environmental, geological and engineering documentation together with required permits, feasibility studies and EU applications together with construction supervision
To solve the issue of wastewater management in Warsaw, the extension and modernisation of the Czajka wastewater treatment plant was planned and designed to increase its throughput from 240,000 m³ per day to 435,300 m³ per day with a simultaneous increase in treatment effectiveness, especially regarding reduction of biogenic compounds. The solution is complemented by expanding the disposal system used to handle sludge resulting from wastewater treatment processes and terminating it with a thermal processing installation.
We help our client meet restricted requirements concerning water quality, drinking water supply, water treatment and waste water standards.
Once implemented, the project allowed drafting of preinvestment analyses as well as project and tender documentation to construct a central system to manage the combined wastewater network with a view to optimum utilisation of reservoir capacities and distribution of wastewater to the Czajka treatment plant. This includes the construction of one reservoir in the form of a collector pipe alongside the Vistula river bank and another reservoir in the green areas that replaced the former treatment line of the Czajka treatment plant, together with connecting wastewater inflow from two pumping stations.
Despite the associated costs, introducing a calibrated wastewater network model will allow achieving quantifiable benefits:
- Optimising the catchment area growth;
- Reducing the amount of investment outlays for future tasks;
- Avoiding the need to pay damages in case of floods and loss of property; and
- Avoiding other consequences of emergency situations.
The project is cofinanced by European Union funds.


The implemention of high water and wastewater standards are essential for a good infrastructure.