Permeable pavements are a type of sustainable urban drainage system (SUDS)technique that are used around the world to infiltrate and treat urban Stormwater runoff and to minimize runoff volumes. Urban stormwater runoff contains significant concentrations of suspended sediments that can cause clogging and reduce the infiltration capacity and effectiveness of permeable pavements. It is important for stormwater managers to be able to determine when the level of clogging has reached an unacceptable level, so that they can schedule maintenance or replacement activities as required. Newly-installed permeable pavements in the Netherlands must demonstrate a minimum infiltration capacity of 194 mm/h (540 l/s/ha). Other commonly used permeable pavement guidelines in the Netherlands recommend that maintenance is undertaken on permeable pavements when the infiltration falls below 0.50 m/d (20.8 mm/h). This study used a newly-developed, full-scale infiltrationtest procedure to evaluate the infiltration performance of eight permeable pavements in five municipalities that had been in service for over seven years in the Netherlands. The determined infiltration capacities vary between 29 and 342 mm/h. Two of the eight pavements show an infiltration capacity higher than 194 mm/h, and all infiltration capacities are higher than 20.8 mm/h. According to the guidelines, this suggests that none of the pavements tested in this study would require immediate maintenance.
One of the goals for the JPI Water funded project INovations for eXtreme Climatic Events (INXCES) is to provide risk assessment tools for urban hydro-climatic events. Combining disciplines increases the capacity to manage and improve the mitigation of the infrastructure for stormwater in urban areas. INXCES is an European collaboration among the cites Bergen, NO, Groningen, NL, Bucharest, RO, and Luleå, SE.In urban areas infrastructure, such as sewage and drainage systems, is installed in the subsurface to cope with surface water and stormwater runoff. However, the natural patterns are preferred hence human effort. A flood model using Digital Elevation Model (DEM) show the flow patterns of stormwater and areas exposed to flooding. Combining mapping of natural flow paths and floodmodelling, areas prone to flooding is accentuated. The subsurface infrastructure in these prone areas are exposed to larger quantities of water during heavy rainfall events, which is becoming more frequent due to climate change. Results from this interdisciplinary study, will give the water and wastewater authority a risk assessment to pinpoint areas where water infrastructure is more exposedto failure, clogging and damages. Furthermore, we argue that areas that are prone to repeated flooding are more exposed for subsidence in the ground. Larger movement in the ground will cause damage to the infrastructure, such ascracking of pipelines and damage to buildings, roads etc. By combining results mentioned above with subsidence data (InSAR date collected from Satellites), a risk assessment map can show areas to prioritize. Subsurface measures such as SUDS (Sustainable Urban Drainage Systems) can be a resilient solution to a recurrent problem in an urban area, as a remediation to flooding (and drought)and as stabilisation of ground conditions.
Although permeable pavements have been used all over the world in recent years to infiltrate and treat stormwater, only limited research has been undertaken to investigate and compare the long-term performance of these sustainable urban drainage system devices. This paper presents the results of an extensive international review of research on the reduction of infiltration capacity of permeable pavements over time. The results of these studies, coupled with specific knowledge of the key environmental factors on the individual research locations and infiltration testing methods used, enables the maintenance of these SUDS to be strategically planned in order to meet specific European and international infiltration capacity guidelines.
