Urban Planning, Ecological Transition, Urban Services and Housing

Barcelona sewer system responds to the need for environmental protection of target sources: Besos and Llobregat rivers, as well as Mediterranean Sea. The aim is to reduce and control the discharge of effluent into these environments. Waste water are driven by to the treatment plant through the sewer system in order to be treated before being poured.

History

Barcelona has sewer systems that have evolved according to the evolution of the city from its inception. First systems, which were discovered by Josep Antoni Brusi, date back to Roman times, but the current sewer system is mostly the result of the engineering work carried out by the distinguished civil engineers Faria and Pedro Garcia. Later on, it was designer by Albert Vilalta and González.

García Faria's Plan

García Faria’s Plan (1886) was a turning point in the history of Barcelona sewer system and, therefore, in the quality of life of its inhabitants. In the introduction, Pedro Garcia Faria recognised that the remodelling project was not attractive, but he stressed the fact that his plan soon produced excellent results. The project was not fully implemented in practice, but it became an important precedent.

The origin of the plan dates back in 1884, when the mayor of Barcelona, ​​Joan Coll i Pujol, created a technical commission to refurbish the sewer system. Garcia Faria himself submitted the foundations of his project in 1885, but they were not approved until the following year. Although the plan was extensive and technically complex, it included some basic points for the further development of the sewerage network:

• Barcelona is divided into three main catchment areas, which are ​​subdivided into another twenty-three catchment areas. It seeks a balance between initial expenses and those which come from conservation.
• The operating system will be the gravity sewer. Cross-section cut shall be at least 1.70m high and 80cm wide. 
• In areas with lower flow and speed, discharge chambers will be installed in order to ensure a proper flow. 
• Chambers must be interconnected by galleries, forcing the owners to include sealed hydraulic traps (open-close mechanism).
• Ventilation of sewers goes through rainwater pipes from the buildings.
• There will be special maintenance and cleaning teams.

Sewer System Master Plan from 1954

In 1952 the guidelines which allowed two years later the development of the Sanitary Sewer Master Plan of Barcelona. This plan shows the deficiencies in Barcelona subsoil, such as the lack of capacity to absorb the entire volume of water or the concentration of sea outlets in just three points (Sants, Horta and Bogatell sewage outlet pipes). It also points out the problem regarding the low slope of sewers pipes from the lower part of the city.

Vilalta Plan (1968)

Barcelona had suffered a strong urban development and dealt a great wave of immigration within its area of influence. The years of uncontrolled urbanization —which consisted of reclassifying systematically lands considered as public land in the Master Plan into building land— brought an intensive densification in the outskirts and the Eixample neighbourhood.

Moreover, during those years there was a change of attitude towards the sea. While the city did not appreciate it much in the past and thought that sea pollution was a source of diseases, in the sixties citizens began to be interested in the coast and enjoy it as much as they could.

The city grew and, as a result, there was an increase in the waterproofed surface and many collectors became obsolete. Therefore, they needed to be refurbished in order to absorb flows in times of flooding. In addition, due the growing economic relevance of flooding zones, the attention was focused on avoiding flooding.

The engineer Albert Vilalta González led the Sewer System Plan between 1967 and 1969. It was written by the Sewer System Management Service from the City Council and was aimed at solving these problems.

One of the main objectives of the plan was to recycle this water in order to reuse it for irrigation and industrial purposes and thus remedy water shortage in Barcelona and its area. Another important goal was to restore some catchment areas to their natural outlet areas for draining the Bogatell outlet as much as possible. It was planned to cut direct sewage outlets in beaches and treat them in treatment plants in order to ensure the quality of seawater for citizens recreation.

Among the most notable achievements of this plan, there are Besos and Bogatell treatment plants —the Bogatell one was demolished recently.

Completion of Vilalta Plan was incomplete due to the lack of enough investment. However, its basic proposals were dutifully transmitted to the plans which have finally been put into practice.

Vilalta Plan is the first serious attempt regarding city planning and draining since Garcia Faria’s project.

Special Plan for Barcelona's Sewer System 1988)

The evolution of the city of Barcelona resulted in a necessary change of the existing sewer system plan. Barcelona Olympic Games, restructuring plans and the consolidation of urbanisation led to drafting Special Plan for Barcelona’s Sewer System Barcelona (“Pla Especial del Clavagueram de Barcelona” or PECB). The plan included an analysis of the overall performance of the network in order to identify flooding zones and analyse the causes. The study also included the municipalities from the metropolitan area, such as Hospitalet, Esplugues and part of Sant Adrià.

One of the most notable innovations of this plan is the use of computational methods, which can simulate the way sewer networks operate depending on the river flow and therefore identify the main problems.

Another key element of this plan is that, for the first time —now is a reality—, it suggested to install a real-time monitoring system of the sewer network by implementing a network of rain and water-level gauges. Besides, it set out a necessary increase in the number of collectors and purification of water in case of flooding.

Special Plan for Barcelona's Sewer System (1997)

The Special Plan for Barcelona's Sewer System (“Pla Especial de Clavagueram de Barcelona” or PECLAB ’97) is the document which planned the sewer system development  into the city water management system. It is aimed at meeting the objectives assigned to the sewer system: collecting and transporting wastewater to treatment plants, avoiding flooding due to rainwater and reducing the environmental impact of dumping sewage during rainy weather..

The extension and modification of the network according to this planning has involved the execution of works worth over 140 million euros since 1997, including the implementation of retention and anti-pollution tanks  (Escola Industrial, Zona Universitària, Bori i Fontestà, Doctors Dolsa, Parc Central de Nou Barris, Joan Miró i Taulat), with a total volume of 440,000 m³ of capacity and several collectors, among which there are ones that belongs to the Enamorats-Aragó streets area. This plan will continue running during the following years, and the expected investment during the years 2004-2007 was over 45 billion euros.

The execution of the several work phases —from planning to executing the work— involves the use of advanced tools support without which the PECLAB not be a document of the quality of the today. These support tools include the modeling system (which allows to know the behavior of water within sewer networks), the territorial information system (in order to find out the network settings) and the remote control system (which allows to operate the system).