OEC starts maintenance work on Vila Caiçara outfall

OEC – Odebrecht Engenharia e Construção started the maintenance works on the Vila Caiçara Submarine Outfall, located in the city of Praia Grande, on the São Paulo coast. The action aims to improve the performance of the Subsea Sanitary Sewage Outfall – Subsystem 3, guaranteeing health conditions for the population and maintaining bathing indices in the region. The equipment is managed by São Paulo State Basic Sanitation Company (SABESP).

The work is at the stage of assembling the outfall, which consists of 1,000 mm high-density polyethylene (HDPE) pipes and reinforced concrete anchor blocks. One thousand meters of pipe have already been laid out of the planned one thousand five hundred meters. A bathymetric survey and seismic survey were also carried out in the area where the outfall will be installed once assembly is complete. The transportation and sinking of the equipment is scheduled to take place in October, depending on the occurrence of favorable sea windows due to the La Niña weather phenomenon. The outfall is scheduled to be definitively installed by the end of this year.

Innovation

The diffuser of the outfall is 270 meters long with 84 risers, developed on site by teams from Sabesp, OEC, SK, Tetra Tech and Transpol. As well as being more efficient at diluting and dispersing effluents, these risers are made up of two sections: one is a more rigid HDPE pipe to prevent siltation, and the other is a flexible hose to prevent further damage from fishing nets.

Submarine outfalls are ocean disposal systems that discharge sanitary effluents into the marine environment, moving them away from the coast and taking advantage of the ocean’s great purification capacity due to its high volume of water. The Vila Caiçara outfall has a flow capacity of 1.4 cubic meters per second and is designed to meet the demand for population growth until 2040.