This report describes the main functionalities the SMART-Control web-based tool T1B Quantitative microbial risk assessment. The tool helps to quantify the pathogen occurrence in source water and their removal by various treatment steps at MAR facilities by using a probabilistic approach. The interactive web-based QMRA tool supports the evidence-based risk assessment to minimize water-related infectious diseases.

Subsurface travel time from the area of recharge to the point of abstraction during MAR is a critical parameter to ensure sufficient attenuation for hygienic parameters and other undesired substances. A new simulation tool has been developed by the SMART-Control project partners KWB and TUD for determination of groundwater hydraulic residence time (HRT) using seasonal temperature fluctuations observed in recharge water and MAR recovery wells. This tool represents a proxy for quick, costs-effective and reliable control of travel time during aquifer passage. Time series of seasonal temperature measurements observed in surface water and abstraction wells can be fitted to sinusoidal functions. Peak values represented as local maxima and local minima and turning points from the fitted sinusoidal curves are used for the approximation of travel times between surface water and abstraction well. The calculated values are adjusted by a thermal retardation factor. The developed tool is userfriendly and offers the possibility to use existing hystorical temperature measurements as well as online sensor data. Data acquisition is resolved through the internal connectivity with other web-tools developed within the SMART-Control project, providing thus an integrated simulation environment.

This report summarizes the work for monitoring of hydraulic residence time (HRT) carried out at the Managed Aquifer Recharge (MAR) site Berlin-Spandau waterworks. The newly installed monitoring system consists of realtime online sensor data and evaluation algorithms implemented as a web-based software tool. The combination of online data with processing tools allows time-efficient HRT evaluation. Apart from HRT estimations, the monitoring also included measurements by flow-through cytometry (FCM), meta-genomic DNA sequencing and classical microbial cultivation-based analysis. FCM cell counting allows to quantitatively detect microbial cells after staining with a DNA-binding fluorescent dye. The aim of FCM measurements was to gain insights on microbial dynamics along the flow path from the infiltration basin to the abstraction well. The FCM device was installed to measure in the infiltration basin, groundwater observation well and abstraction well in a continuously flowing sampling line that allowed for automatic and continuous monitoring in water. Microbial indicators of viruses, bacteria and protozoa were sampled and analysed by classical cultivation-based methods in parallel to the FCM measurements. The combination of FCM with cultivation-based methods aimed to establish an indicative reference cell count representing a hygienically safe water. The high-frequency flow cytometry data revealed decreasing order of total cell counts from surface water in the infiltration basin water to groundwater in the abstraction well. The fairly constant measurements in the abstraction well may allow to use FCM fingerprinting as a fast monitoring tool in combination with cultivation based methods. However, long-term measurements of FCM for at least 6 months are recommended to assess seasonal fluctuation in both source water and groundwater. Water samples were in addition characterised by DNA sequencing enabling a complete "meta genomic" analysis and taxonomic profiling including bacterial, archaea, viral, eukaryotic DNA. The DNA sequencing in combination with FCM measurements showed that total cell counts decreased along the flow path while the biodiversity increased.

The types and objectives to apply managed aquifer recharge (MAR) are manifold and so are the risks that can arise during the planning, implementation and operation of a MAR facility. In general, operational, regulatory, business, human health, and environmental risks can occur and should be identified already during the planning and implementation stage to apply preventive measures and secure the safe and realibale operation of a MAR facility. This report represents risk assessment based on recommendations of international guidelines (AlcaldeSanz and Gawlik, 2017; NRMMC-EPHC-NHMRC, 2008; WHO, 2009, 2011) at six MAR sites which are at different stages of development. Three case studies are at the feasibility or pilot stage: two ASR systems in João Pessoa and Recife, Brazil and one induced bank filtration site at the Beberibe River in Brazil, and three case studies at the operational stage: one SAT system in the Ezousa catchment in Cyprus, and two infiltration basin systems in Hyères, France (Aquarenova site) and Berlin-Spandau, Germany. The entrylevel assessment according to the Australian guidelines (NRMMC-EPHC-NHMRC, 2009) has been conducted for the feasibility or pilot scale schemes For fully operational MAR schemes, in addition to the entry-level assessment, the degree of difficulty assessment and the maximal risk assessment were carried out. At all stages of site development, risk assessment helps to identify and characterize potential hazards that may cause risks to human health and the environment. This report may be used to assist in clarifying which actions or further investigations are required to identify and reduce the uncertainty of risks and to implement remediation measures if necessary. In addition, this report intends to show how sitespecific hazards have been assessed to varying degrees depending upon the level of risk assessed at each project development stage.