Rapid changes in the urban environment due to growth puts the urban water cycle out of balance, hence, affecting other surface and subsurface processes, such as subsidence and surface water management.Subsidence of the ground is causing risk and hazard, as well as unexpected costs. This newly, November 2018, launched tool InSARNorge is Open Access and part of the Copernicus program.In a recent study (Venvik et al. submitted) datasets from InSAR satellites showing subsidence are combined with data from flood modelling in two different analytical methods using ArcGIS tools to develop a risk assessment map for areas most prone to the combination of both flooding and subsidence. Applying usercentred principles, this work focuses on methods for risk assessment maps as a support tool to locate areas where mitigation of subsidence and adaptation for surface water management will be most efficient and measures can be implemented. The results of the methods for risk assessment maps show that one of the methods give significant results compared to the other method. Such method will be a helpful tool for decision-makers when prioritizing areas for measures such as Sustainable urban Drainage Systems (SuDS).The study is related to the JPI Water funded project INXCES (www.inxces.eu).
Stormwaters, flowing into storm sewers, are known to significantly increase the annual pollutant loads entering urban receiving waters and this results in significant degradation of the receiving water quality. Knowledge of the characteristics of stormwater pollution enables urban planners to incorporate the most appropriate stormwater management strategies to mitigate the effects of stormwater pollution on downstream receiving waters. This requires detailed information on stormwater quality, such as pollutant types, sediment particle size distributions, and how soluble pollutants and heavy metals attach themselves to sediment particles. This study monitored stormwater pollution levels at over 150 locations throughout the Netherlands. The monitoring has been ongoing for nearly 15 years and a total of 7,652 individual events have been monitored to date. This makes the database the largest stormwater quality database in Europe. The study compared the results to those presented in contemporary international stormwater quality research literature. The study found that the pollution levels at many of the Dutch test sites did not meet the requirements of the European Water Framework Directive (WFD) and Dutch Water Quality Standards. Results of the study are presented and recommendations are made on how to improve water quality with the implementation of Sustainable Urban Drainage Systems (SUDS) devices.
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.
