Evaluation of the effect of soil type on the infiltrationtrench clogging: a long term approach

In recent years, limitations linked to traditional urban drainage schemes have been pointed out andnew approaches were developed introducing more natural methods for retaining and/or disposing ofstormwater. Such practices include infiltration and storage tanks in order to reduce the peak flow andretain part of the polluting components. The impact of such practices on stormwater quantity andquality is not easily assessable because of the complexity of physical and chemical processesinvolved. In such cases, integrated urban drainage models may play a relevant role providing tools forlong term analysis of infiltration structures efficiency. In this study, the effect of the cloggingphenomenon has been assessed by means of a long term modelling approach. In particular, asimplified conceptual modelling approach for the simulation of the infiltration trenches has beenworked out. The analysis has been applied considering different soils as well as different designcriteria. Particular care was addressed to the simulation of infiltration structures consideringperformance reduction due to clogging phenomena. On the basis of a long-term simulation of 6 yearsrain data, the performance as well as the effectiveness of an infiltration trench measure are assessed.The study confirmed the important role played by the clogging phenomenon on such infiltrationstructures.