The Collection and transmission network of wastewater of Ahwaz metropolis in south west of Iran is one of the largest and most complicated projects currently being implemented in the country in the field of urban wastewater. Karun as the largest river of Iran at the middle of city, a metropolis with over 20.000 ha as area and meanwhile flat surface and very slight slope, necessity of using a lot of pumping stations, low bearing capacity and geotechnical specifications of soil and the level of water table and behavior of soils under the soil-water interactions, hot weather and high humidity etc. are some difficulties of the project.
Based on the master plan of Ahwaz wastewater, east and west side of Karun river have different wastewater treatment plants. The largest pump station of Ahwaz wastewater system which is considered the largest urban wastewater pump station in the middle east located before the East Ahwaz wastewater treatment plant, with a capacity of 7920 liters per second and 2+8 electropumps that each electropump’s power is 400 kW. This station is very important to normalize the situation of wastewater transmission of Ahwaz metropolis to the treatment.
This station has two inlet pipelines with diameters of 1600 and 2400 mm and four output pipelines with diameters of 1400 mm. Diaphragm wall of the station is built using 141 piles with a depth of 25 meters. This is a Secant Piled Wall as a retaining wall constructed for ground retention prior to excavation. The wall is formed by constructing alternating primary (female) and secondary (male) piles where the secondary piles partially cut into either side of the primary piles in order to form a continuous impervious structure.
At present, the overall progress of implementing operations has reached about 63%, and in parallel, the procurement of relevant equipment is also ongoing through contractor.
