Eduardo Martínez-Gomariz (Spain) 1; Salvador Vela (Spain) 1; Beniamino Russo (Spain) 2; Manuel Gómez (Spain) 3; Aurea Plumed (Spain) 4
1 - Cetaqua, Water Technology Centre; 2 - Aquatec; 3 - Flumen Research Institute (Technical University of Catalonia); 4 - Barcelona City Council
When an urban flood occurs water flows usually contain debris which could even be as massive as vehicles depending mainly on how high the velocity and water depth are. In urban areas, due to the great amount of daily human activities, several types of elements potentially washed away by floodwaters can be found. An example is waste municipal containers which may lose their stability, thereby allowing debris and leachate to escape and contaminate the flood water. Moreover, once a container loss its stability it can further constrict a narrow street and increase flooding, thereby creating a closed basin with no outlet for runoff and exacerbating the effects of flooding. Therefore, the waste containers stability when exposed to flooding is definitely an environmental, safety and health concern to be addressed.
The regular collection of household waste municipal service for large Spanish cities is frequently conducted through street containers as a step before the solid waste is dumped in landfills. Particularly, Barcelona opts for a recycling collection including five different fraction-types of containers. There are a total of 27,134 containers, which can be classified either according to the fraction they contain (i.e. waste, organic, paper and cardboard, packaging, and glass), their volume in litres (i.e. 3,200; 3,000; 2,400; 2,200; and 1,800) or the way they are loaded (i.e. lateral, bilateral, rear, underground). All citizens have recycling collection containers located less than 100 meters from their home.
In a comprehensive urban resilience assessment within RESCCUE project, interdependencies and cascading effects due to failure caused by climate event impacts are taken into account. This assessment is carried out through two different scales approaches: a holistic study (an all-city study by employing the Hazur® platform), and specific studies for different urban services affected by a specific climate event, such as municipal solid waste management affected by floods.
In this research, stability functions for waste containers exposed to urban floods have been derived. These thresholds have been employed to analyse the containers’ potential behaviour against floods in Barcelona. In order to validate the model a historical rainfall has been modelled and low-return-period design storms (i.e. 2, 5 and 10 years) have been performed to assess the containers vulnerability against floods for frequent rainfall events. Once the number of potentially unstable containers has been estimated, adaptation measures have been proposed in order to increase the resilience of waste sector against urban floods in Barcelona.