Fuenlabrada–Culebro WWTP Primary Sewer Collector

The Fuenlabrada–Culebro WWTP Primary Sewer Collector is one of the most significant hydraulic infrastructure projects developed to improve the conveyance of wastewater and stormwater in the southern metropolitan area of Madrid. The project was designed to connect the Fuenlabrada–Culebro Wastewater Treatment Plant (WWTP) to the Getafe collector system through a high-capacity conveyance structure capable of transporting up to 25 m³/s, addressing the drainage limitations created by rapid urban development and the area’s minimal natural gradients. The infrastructure extends for approximately 8.1 km and was constructed as an in-situ reinforced concrete gallery, a solution that provided substantially greater hydraulic capacity than conventional precast pipeline systems

From a reinforcement engineering perspective, the project represented a major industrialization challenge due to the exceptionally high production rates required during construction. The works were organized around 23.5 m long travelling formwork systems, designed to achieve production rates of up to 95 m³ of concrete and 10 tonnes of reinforcement steel per day for each formwork unit. To meet these demanding targets, ERSIGROUP developed a dedicated reinforcement solution based on prefabricated folded welded reinforcement panels, manufactured under controlled industrial conditions and delivered to site ready for direct installation onto the previously cast concrete base slab

The optimization of the reinforcement design allowed reinforcement installation activities to be carried out independently from formwork erection and concrete placement operations, eliminating construction bottlenecks and significantly improving productivity. To minimize lap splices and reduce unnecessary steel consumption, large-format unidirectional welded reinforcement panels were specifically developed for both the foundation slab and wall reinforcement. Particular attention was given to the reinforcement system for the gallery vault, which incorporated curved reinforcement panels measuring up to 3.8 m in width and 12 m in length, supported by semi-circular stiffening bars capable of carrying both the self-weight of the reinforcement cage and the loads associated with installation activities

The combination of detailed engineering, industrialized reinforcement fabrication, reinforcement optimization and advanced construction planning enabled exceptionally high production rates, achieving installation outputs of up to 47 linear metres of collector per day. The use of industrialized reinforcement solutions developed by ERSIGROUP proved essential in ensuring the quality, safety and efficiency required for the successful delivery of this technically demanding hydraulic infrastructure project

Key Milestones

• 8.1 km primary wastewater collector connecting the Fuenlabrada–Culebro WWTP to the Getafe collector system
• Hydraulic conveyance capacity of up to 25 m³/s
• More than 30,000 m³ of reinforced concrete placed
• Over 4,300 tonnes of fabricated and installed reinforcing steel
• Use of 23.5 m long travelling formwork systems to maximize construction productivity
• Production rates of up to 10 tonnes of reinforcement steel per day per formwork unit
• Development and implementation of prefabricated folded welded reinforcement panels for foundations, walls and vault structures
• Fabrication of curved reinforcement panels for the vault measuring up to 3.8 m in width and 12 m in length
• Execution of 375.8 m of jacked reinforced concrete pipe crossings (Ø 3,000 mm) beneath existing transport infrastructure
• Achievement of construction outputs of up to 47 linear metres of collector per day
• Implementation of industrialized reinforcement fabrication and preassembly processes developed by ERSIGROUP, significantly improving productivity, quality control and construction safety