By using specially designed equipment to avoid a negative impact on the area, as well as the careful implementation of waste separation techniques, this project rehabilitates and repairs structural elements of the bridge, while protecting the environment.
 
Located in the protected natural environment of Las Marismas del Odiel, a UNESCO biosphere reserve, the Santa Eulalia siphon bridge requires an intervention that involves no risk to biodiversity.

Thus, a specific trolley was designed for the site, which even exceeds the initial proposal envisaged in the tender because it is adapted for linear movement. It is a structure made up of scaffolding, which moves parallel and perpendicular to the deck, facilitating the work without the risk of environmental impact.

In addition, the placement of special meshes and thick geotextiles (3-4 mm) allows the formation of a watertight enclosure to prevent any waste from falling. A bridge inspection platform complements this infrastructure to prevent possible accidents resulting from falls from different levels.

Other major environmental actions for the project included the use of a tanker truck for the collection of sludge from the injection of the piles, the correct segregation of waste and plastics to avoid contamination of the vegetation, and the monitoring of soil from the excavation for reuse on the same site.

The bridge, built more than 50 years ago, was showing signs of wear and tear due to use and exposure to the saline environment, so the rehabilitation work began by reinforcing the existing foundations with micropiles.

Hydrodemolition and hydrocleaning techniques are applied for the repair of the deck, and the geotextiles act as filters to retain as much waste as possible and prevent it from penetrating into the ground during these tasks. The repair of concrete joints and the application of paint as a finishing touch to the work complement projects that have had a major impact in the region. 

Vital for the economy of Huelva, the Santa Eulalia siphon bridge not only links the municipalities of Huelva and Aljaraque, but also contains the pipes that guarantee the water supply for 150,000 people from different towns, as well as for the transfer of water to Doñana. 

Aware of the importance of the entire operation, Sorigué’s construction team carefully plans each stage of the work alongside the Quality, Prevention and Environment Department, to ensure that the agreed deadlines are met, and the environment is fully protected.