- Complete rehabilitation of the sewage and stormwater system
- Underground storage tank stores 2,430,000 liters of water
- Produced by Hobas in Poland
In the view of environmental influences and the expansion of urban areas, the issue of flood prevention becomes a key task for urban infrastructure. Hobas, the manufacturer of GRP pipe systems for sewage and stormwater applications, has taken on the task and recently installed a 2,410 m³ large retention system DN 3600 in the Polish city of DabrowaGórniczawith.
Complete rehabilitation of sewage and stormwater system
DabrowaGórnicza is carrying out a number of large-scale projects, including in the field of water and wastewater management due to the poor technical condition of the network and the insufficient capacity of the existing stormwater sewer during heavy rain. In order to prevent floods, the city opted for a complete rehabilitation of the sewage and stormwater system. In the event of heavy rainfalls, the excess water shall be discharged into a stormwater retention tank and then gradually pumped out. The very limited space on site ruled out the alternative option of a second sewer.
2,430,000 liters of water, contained in 3,600mm pipes
Hobas designed the underground storage tank with a capacity of 2,410 m³. The reservoir is built of four 62 m rows of GRP Pipes DN 3600, shafts, as well as bends with in- and outlet pipes and channels. The individual elements were jointed with Hobas FW Couplings (FWC) and two assembly couplings were selected to close the reservoir. Due to the pipe’s small outside diameter in relation to the inside diameter, the installation area could be reduced. A ventilation system with PVC pipes was laminated to the GRP Pipes.
The storage system is part of a new stormwater drainage system which is currently being built from DN 400-1400 pipes (PN 1, SN 10000). The installation of the sewers commenced in February 2014 and will continue until the end of 2014. Hobas Poland produced the required GRP pipes, fittings, and shafts. Due to the large size of the fittings, the deliveries took place at night.
The project also includes a pumping station with two pumps to discharge the rainwater accumulated in the tank. The two pumps are an integral part of the tank and located in a shaft DN 2000. They operate periodically, depending on the precipitation intensity. Assuming a performance of the pumping station of 30 l/sec, it takes about 22 hours to drain the tank.
Year of installation: 2014
Installation time: Tank 1 month, Sewer system 10 months
Total length of pipe: 1.7 km
Capacity: 2,410 m³ (4 x 62 m)
Diameter: Tank DN 3600, Sewersystem DN 400-1400
Pressure class: PN 1
Stiffness class: SN 10000
Application: Retention system, sewer system
Installation method: Open trench