In recent decades, emerging contaminants (ECs) have surfaced as one of the key environmental problems threatening ecosystems and public health. Most emerging contaminants are present in low concentrations, and therefore often remain undetected and are also referred to as ‘micropollutants’. Despite this, many ECs raise considerable concerns regarding their impacts on human and environmental health. DEMEAU (Demonstration of promising technologies to address emerging contaminants in water and wastewater), a European Seventh Framework Programme (EU-FP7, 2013-2015) project, aimed to tackle ECs in drinking and wastewater by advancing the uptake of knowledge, prototypes, practices and removal technologies. The project followed a solutions-oriented approach using applied research and demonstration sites, and explored four promising technologies for EC removal and/or degradation: Managed Aquifer Recharge (MAR), Hybrid Ceramic Membrane Filtration (HCMF), Automatic Neural Net Control Systems (ANCS) and Advanced Oxidation Techniques (AOT). Furthermore, Bioassays (BA) were investigated as an effect-based monitoring tool. This article shares new findings for each approach and their potential for widespread integration in the drinking- and wastewater sector. Research results from DEMEAU demonstration sites show that opportunities for synergies among these developments offer the most promising and effective methods for tackling ECs in the water sector.

Different types of managed aquifer recharge (MAR) schemes are widely distributed and applied on various scales and for various purposes in the European countries, but a systematic categorization and compilation of data has been missing up to now. The European MAR catalogue presented herein contains various key parameters collected from the available literature. The catalogue includes 224 currently active MAR sites found in 23 European countries. Large quantities of drinking water are produced by MAR sites in Hungary, Slovakia, the Netherlands, Germany, Finland, Poland, Switzerland and France. This inventory highlights that, for over a century, MAR has played an important role in the development of European water supply and contributes to drinking-water production substantially. This development has occurred autonomously, with “trial-and-error” within the full range of climatically and hydrogeologically diverse conditions of the European countries. For the future, MAR has the potential to facilitate optimal (re)use and storage of available water resources and to take advantage of the natural purification and low energy requirements during MAR operations. Particularly with respect to the re-use of wastewater treatment-plant effluent and stormwater, which is currently underdeveloped, the use of MAR can support the public acceptance of such water-resource efficient schemes. Particularly for the highly productive and urbanized coastal zones, where the pressure on freshwater supplies increases by growing water demand, salinization and increased agricultural needs for food production (such as along the Mediterranean and North Sea coasts), MAR is expected to be increasingly relied on in Europe.

This project report summarizes work conducted in work package 12 of the DEMEAU project. Along with Deliverable 12.1 it covers all tasks from work package 12 as formulated in the Description of Work (DoW). This report contains information about (pre-) feasibility studies, design recommendations and pre-treatment options for different types of MAR. The wide range of hydrogeological features encountered in reality makes a site-by-site approach indispensable. As part of this effort the hydrogeological pre-requisites for surface spreading and deep well injection techniques are described in detail. In chapter 2, ten essential hydrogeological parameters are defined by objective criterias. The following chapter outlines and describes how to obtain these essential hydrogeological parameters. This feasibility assessment starts with the screening of the potential site based on a structured procedure. Site investigations start with relatively cheap but numerous field and laboratory testing and continue to more cost-demanding but less numerous tests. With this procedure it is possible to carry out technical site feasibility in a costand time efficient way. The fourth chapter investigates the International Hydrogeological Map of Europe (IHME 1500) as a planning basis for pre-feasibility of new MAR sites. It was found that the IHME 1500 is useful for a pre-assessment, but detailed regional and local scale maps (and investigations) are additionally necessary to effectively assess hydrogeological features. The final chapter deals with pre-treatment options for MAR. Pre-treatment is necessary to remove critical contaminants from the source water to i) enhance system performance and removal efficiencies, ii) ensure the long-term functioning of the system, iii) meet regulatory demands and iv) ensure beneficial uses of the aquifer beyond the attenuation zone. Available pre-treatment methods in relation to source water type and intended end-use are described. Based on chemical concentrations in source water and intended end-use the most appropriate pre-treatment method can be assessed from a table. Altogether this report thus provides guidance in designing new MAR systems based on a sound hydrogeological site characterisation and pre-feasibility assessment based on available information and parameters obtained from structured investigations.

Different types of managed aquifer recharge (MAR) schemes are widely distributed and applied on various scales in the European countries, but no systematic categorization and compilation existed up to now. The European MAR catalogue presented herein includes a wide range of parameters, e.g. operational information, hydrogeological properties and water quality monitoring for different types of MAR. The database includes currently 270 MAR sites, but is neither a representative nor an exhaustive data compilation. Nevertheless, based on the available data it is shown that MAR plays an important role in the European water supply producing large water quantities for the domestic water supply.

The present study provides an overview of geogenic contamination, its occurrence, impacts and possible treatment options for drinking water production. Natural background and anthropogenic contamination can be differentiated using an algorithm based on the frequency distribution of measured substance concentrations. Case studies for geogenic contaminants such as ammonium, fl uoride, chloride, sulfate and uranium are discussed based on the origin, occurrence, controlling factors and treatment options. It is suggested that, in case of occurrence of geogenic contaminants, water must be treated or alternative sources need to be found, e.g., managed aquifer recharge, prior to the distribution as drinking water.

The EU-funded R&D project DEMEAU addresses the fate of emerging pollutants in water and waste water treatment, e.g. Managed Aquifer Recharge (MAR). For MAR the objectives are to mobilize existing experience from different European study sites and to develop a systematic approach for the authorization of new recharge schemes in compliance with the European water and groundwater directives. The activities will cover the issue of infiltrating and injecting treated wastewater as well as developing guidance on optimum design and operation of infiltration facilities. In order to demonstrate the effects of typical existing European MAR systems onto groundwater availability and groundwater quality with specific focus on trace organics, a comprehensive relational database (catalogue) on European MAR systems was created to ensure efficient management of available data. By means of the built-in user forms, queries, and reports, database users are enabled to not only view and enter records but also to quickly process the data to extract needed information. In total, 59 different parameters were selected in order to describe about 270 documented MAR sites in 23 countries in Europe. These parameters were then divided up into four main groups (general information, technical data, hydrogeological parameters and monitoring activities) plus references. The database was created using standard software (MS ACCESS) and references were managed by open source software (JABREF). The compiled data on European MAR sites was taken from a variety of different source types, including scientific articles, books, PhD, diploma and master's theses, presentations, technical documents, reports from previous national and EU research projects, personal communication with specialists, operators and water authorities, community and operator websites, newspaper articles, and Google Earth (for geographic coordinates to create overview maps). On the basis of this database a classification system for the MAR sites found in Europe will be developed that can be used for deriving site-specific pre-requisites and design criteria as guidance for the authorization of for new sites.

The EU-funded R&D project DEMEAU addresses the fate of emerging pollutants in water and waste water treatment, e.g. Managed Aquifer Recharge (MAR). For MAR the objectives are to mobilize existing experience from different European study sites and to develop a systematic approach for the authorization of new recharge schemes in compliance with the European water and groundwater directives. The activities will cover the issue of infiltrating and injecting treated wastewater as well as developing guidance on optimum design and operation of infiltration facilities. In order to demonstrate the effects of typical existing European MAR systems onto groundwater availability and groundwater quality with specific focus on trace organics, a comprehensive relational database (catalogue) on European MAR systems was created to ensure efficient management of available data. By means of the built-in user forms, queries, and reports, database users are enabled to not only view and enter records but also to quickly process the data to extract needed information. In total, 59 different parameters were selected in order to describe about 270 documented MAR sites in 23 countries in Europe. These parameters were then divided up into four main groups (general information, technical data, hydrogeological parameters and monitoring activities) plus references. The database was created using standard software (MS ACCESS) and references were managed by open source software (JABREF). The compiled data on European MAR sites was taken from a variety of different source types, including scientific articles, books, PhD, diploma and master's theses, presentations, technical documents, reports from previous national and EU research projects, personal communication with specialists, operators and water authorities, community and operator websites, newspaper articles, and Google Earth (for geographic coordinates to create overview maps). On the basis of this database a classification system for the MAR sites found in Europe will be developed that can be used for deriving site-specific pre-requisites and design criteria as guidance for the authorization of for new sites.