Multi-criteria decision making methods (MCDM) have been widely used throughout the last years to assist project contractors in selection processes related to the construction field. Sustainable urban drainage systems (SUDS) are an especially suitable discipline to implement these techniques, since they involve important impacts on each branch of sustainability: economy, environment and society.\ud Considering that pervious pavements constitute an efficient solution to manage urban stormwater runoff as a source control system, this paper presents a multi-criteria approach based on the Integrated Value Model for Sustainable Assessments (MIVES) method to facilitate their proper selection. Given the lack of accurate information to shape the behavior of the alternatives regarding some of the criteria defining\ud the decision-making environment, a series of variables are modeled by executing stochastic simulations based on the Monte Carlo methods. Additionally, a group of ten experts from various sectors related to water management was requested to provide their opinions about the importance of the set of selected criteria, according to the comparison levels of the Analytic Hierarchy Process (AHP). These judgments are\ud converted into triangular fuzzy numbers, in order to capture the vagueness that human attitude entails when making judgments. A case of study in which the three major types of pervious pavements (porous asphalt, porous concrete and interlocking concrete pavers) are evaluated is presented to demonstrate the potential of the model

The Spanish climate is full of contrasts, with torrential rains and long droughts; under these conditions, appropriate water management is essential. In Spain, until the end of the twentieth century, water management and legislative development lagged behind other more developed countries. Nowadays, great efforts are being made to reverse this situation and improve both water management and legislation in order to control the two main problems related to stormwater management in cities: floods and diffuse pollution. In this context, Sustainable Urban Drainage Systems (SUDS) were developed as the main solution to these problems. The study of these techniques started in the 1970s in the USA, but they were not studied in Spain until 1993 when the University of Cantabria and CLABSA started to look into solutions for stormwater management. After 20 years of research and application, sustainable drainage in Spain is still behind other countries in spite of the efforts to change this situation, notably by the University of Cantabria with 10 years of experience in these techniques, mainly regarding pervious pavements, where more than 13 related research projects have been carried out. The future challenges focus on the application of pervious pavements for Urban Hydrological Rehabilitation.

Permeable pavements have been used widely across the world to manage urban stormwater. The hydrological behaviour of permeable surfaces is a complex process affected by many factors, such as rainfall intensity, rainfall duration, pavement geometrical conditions, and clogging level of the permeable surface, amongst others. This laboratory study was carried out to assess the influence of clogging level and rainfall intensity on the infiltration capacity of porous mixture surfaces used in Permeable Pavement Systems (PPS). Porous Concrete (PC) and Porous Asphalt (PA) mixtures with different air void contents (15%, 20%, and 25%) were subject to different clogging scenarios by using varying sediment loads (0, 500, and 1000 g/m²). Permeability experiments were carried out for each clogging scenario through a new rainfall simulator specially developed, tailored, and calibrated for the laboratory simulation of a wide range of rainfall events. Permeability measurements were taken under all different scenarios as a result of the combination of the different rainfall events (50, 100, and 150 mm/h) simulated over the specimens of porous mixtures and the sediment loads applied to them. The results showed that the PC mixtures tested perform better than the PA ones in terms of infiltration capacity, showing less potential for clogging and being more easily cleaned by the wash-off produced by the simulated rainfall events.

Pervious pavements have become one of the most used sustainable urban drainage system (SUDS) techniques in car parks. This research paper presents the results of monitoring water quality from several experimental car park areas designed and constructed in Spain with bays made of interlocking concrete block pavement, porous asphalt, polymer-modified porous concrete and reinforced grass with plastic and concrete cells. Moreover, two different sub-base materials were used (limestone aggregates and basic oxygen furnace slag). This study therefore encompasses the majority of the materials used as permeable surfaces and sub-base layers all over the world. Effluent from the test bays was monitored for dissolved oxygen, pH, electric conductivity, total suspended solids, turbidity and total petroleum hydrocarbons in order to analyze the behaviour shown by each combination of surface and sub-base materials. In addition, permeability tests were undertaken in all car parks using the ‘Laboratorio Caminos Santander’ permeameter and the Cantabrian Portable Infiltrometer. All results are presented together with the influence of surface and sub-base materials on water quality indicators using bivariate correlation statistical analysis at a confidence level of 95%. The polymer-modified porous concrete surface course in combination with limestone aggregate sub-base presented the best performance.

The use of cellulose fibers (CF) has become a common technique for reducing draindown problems in porous asphalt (PA) mixtures, helping to increase the bitumen content and providing thicker binder films. In this research, a laboratory study was conducted to assess the suitability of using recycled Tetra Brick Aseptic (TBA) containers as an environmentally friendly substitute for virgin cellulose fibers used in PA pavements. The results obtained showed that recycled TBA material was a suitable addition for PA mixtures, providing similar, or sometimes greater, improvements than commercial CF.This study was funded by the Spanish Ministry of Economy and Competitiveness through the research project BIA2012-32463 with funds from the State General Budget (PGE) and the European Regional Development Fund (ERDF). The authors wish to thank the GCS, and GITECO research groups of the University of Cantabria. Valerio C. Andrés-Valeri would also like to thank the Spanish Ministry of Economy and Competitiveness for the Predoctoral Fellowship BES-2013-062604, for funding his research activity at the University of Cantabria

Service life of permeable pavements is strongly influenced by the infiltration capacity reduction produced due to the progressive clogging of the interconnected pores. This study focused on the effect of rainfall intensity and duration as well as the pavement slope, on the clogging and de-clogging processes of permeable pavements. For this purpose, a rainfall simulator was used in order to test porous asphalt and pervious concrete samples with void contents of 15, 20 and 25%. In order to simulate the permeability reduction in permeable pavements during their service life, test samples were clogged using three different sediment concentrations: 0.5, 1.0 and 2.0 kg/m². Three different rainfall intensities (50, 100 and 150 mm/h) and two different rainfall durations (15 and 30 min) were tested over the test samples. The infiltration capacity of the test samples was assessed in newly built conditions, and for each clogging scenario before and after rainfall simulations. Results showed that rainfall patterns as well as pavement slope significantly affect the infiltration capacity of clogged permeable materials, being higher after longer and intense rainfall events and for lower pavement slopes. Overall, PC mixture showed a best performance in terms of infiltration capacity and self-cleaning capabilities.