Conservation

The sewage system network of the city of Barcelona has a high-technology maintenance system. Two types can be distinguished:

• Corrective maintenance: action is taken after breakdowns are produced.
• Preventive maintenance: action is directed at reducing breakdowns.

* Corrective method
This considers all the urgent and unforeseen repair work which demand immediate action. For this work there are several work teams.
With a light vehicle equipped with specific machinery, they can quickly attend to any urgent incident.

Examples of some of these jobs are:

• Repairing frames and inspection covers
• Repairing trashracks
• Punctual repairs in the interior of the sewage system
• Positioning and repairing handrails and protecting bars in chutes
• Repairing sinkings and cave-ins

* Methods of preventive maintenance
Carrying out this type of maintenance means that breakdowns can be anticipated, thus improving the service and reducing costs, giving priority to the most critical points. To do this, there are several permanent teams specialised in each of these jobs. Preventive maintenance work is done taking into account annual planning, and for each of the repair jobs a detailed constructive project is drawn up.
Examples of some of these jobs are:

• Substituting frames and covers
• Substituting trashracks
• Change of steps in the inspection pits
• Reconstruction of skerbs
• Positioning clay troughs
• Renovation of semi-visitable and tubular sewers
• Renovation of interior linings
• Consolidation of structures

* Methodology
The methodology used differs depending on whether it deals with a non-destructive internal rehabilitation or a total one.

- The non-destructive internal rehabilitation may be carried in the greater part of the Barcelona network, since it mostly of the visitable type.This allows repairs to be made from the interior of the sewage system, thus eliminating the environmental impact involved when digging up the ground.

This non-destructive rehabilitation methodology is indispensable in those cases where the surface cannot be affected, like for example historic centres, below constructions etc.

- The total rehabilitation, of the destructive type, is generally used on the network with non-visitable tubular sections. In these cases, the repairs are more aggressive for the soil and they are visible, since they are exterior.

For the surface elements: inspection covers and outlet trashracks, nuisance to the citizens is considerably reduced by using special fast-setting materials which allow traffic to pas within one hour.