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Groundwater depletion through drinking water abstraction, irrigation or climate change generally has a negative impact on terrestrial groundwater-dependent ecosystems. Towards the concept of ecologically sustainable groundwater abstraction management, a method is needed to uniformly evaluate different areas on the basis of biotic value. Biotic value represents the natural value of a habitat for protected species conservation (nature value). Established and currently indispensable methods of landscape planning generally evaluate habitat function via the habitats, whereby the inventory of animal species is largely ignored. Thus, there is a crucial need for additional species-based animal and ecology data to be methodologically standardised, quantified and incorporated into planning practice. Initial faunistic assessment methods already have been developed and applied in practice, but are generally limited to single groups of species, such as birds and bird breeding areas. In this paper, we present a new method that, in addition to the established habitat type module, incorporates a species module to enable multiple plant or animal species besides birds to be included in biotic area assessment. The use of this approach allows for standardized comparison of changing biotic area values over time, or among, for example, European Natura 2000 areas. By considering groundwater dependency and groundwater impact, special attention can be paid to derivation of the hydroecological vulnerability. This method makes it possible to calculate further vulnerabilities by considering other environmental threat factors. We test this method in the case study of the drinking water catchment area of the city of Karlsruhe.

Die okologisch nachhaltige Bewirtschaftung von Grundwasservorkommen zum Schutz grundwasserabhangiger Okosysteme ist gesetzlich vorgeschrieben. In der aktuellen Genehmigungspraxis werden Grundwasserentnahmen hinsichtlich ihrer Umweltwirkungen bislang isoliert bewertet, auch wenn bei groseren Wasserversorgern durch den von ausen vorgegebenen Wasserbedarf die Entnahmemengen der einzelnen Wassergewinnungsanlagen voneinander abhangig sind. Im Rahmen der Konzeption eines okologischen Entnahmemanagements fur die Wasserwerke der Stadt Karlsruhe wurden mehrere Arbeitsschritte durchgefuhrt: (1) Aufbau eines regionalen numerischen instationaren Grundwasserstromungsmodells, das die einzelnen, sich hydraulisch beeinflussenden Wasserwerke mit ihren Einzugsgebieten beinhaltet; (2) Ermittlung wasserrechtlich, technisch und hygienisch abgesicherter Minimalentnahmen, die in der Praxis realisierbar sind; (3) Ermittlung des raum-zeitlichen Steuerungspotenzials mittels Simulationsstudien des Wirkraums eines okologischen Entnahmemanagements. Da das Wasserdefizit, das aus Forderreduzierungen eines Wasserwerks resultiert, auf andere Wasserwerke verteilt werden muss, konnen okologische Verbesserungen an einem Ort mit okologischen Verschlechterungen anderenorts einhergehen. In auf den Ergebnissen aufbauenden Arbeiten wird die hydrookologische Vulnerabilitat des Bewirtschaftungsgebiets beschrieben und ein Verfahren zur okologischen Bewertung unterschiedlicher Entnahmeszenarien entwickelt.

In the last years, there has been a great interest in the complex interactions between energy and water, known as the Water-Energy Nexus.1 Free and unrestricted availability and access to energy and water enables the growth of an economy and supports the quality of life. The Water-Energy Nexus is considered as one of the most important multidisciplinary challenges2 that the water market globally growing has to face in the forthcoming years. Currently, many water systems are not managed in terms of long term sustainability. Water Utilities (WU) are faced to further challenges, such as aging of their infrastructure and poor cost-recovery, leading to a lack of finance for operation and maintenance (O&M). Energy is required in all stages of water production and distribution, from abstraction over treatment to transportation. Energy costs are a top-of-mind concern for WU, regardless of the geography, size and level of water network efficiency.3 On the other hand, in developing countries WU are having a hard time to either improve their services or expand their network to unserved neighbourhoods. Regarding all this facts, and considering an economic and competitive scenario which forces to respond to pressures from various fields (market, technology, society...), lead to the need to implement new methods and processes that can meet these growing demands and to try to manage responses and actions in real time. Intelligent software solutions can be applied to networks, whether they have either smart metering and large amounts of data or less recorded data. They enhance the operators’ knowledge of this data, turn it into useful information for decision-making related to the operation, maintenance and the design of the water supply network. In this paper, an application of an intelligent software solution is presented. WatEner, a smart Information and Communication Technology (ICT) solution that combines the key factors of energy consumption with further operational requirements of drinking water supply to improve the management of water supply networks, has been tested with good results by the WU of the city of Karlsruhe, a water rich area in North-West - Europe where the main objective was to save energy in the drinking water distribution. As a conclusion, a non-structural solution for the water-energy nexus can have a great impact on several matters (e.g. climate change, carbon footprint, WUs balance sheets, water losses) with reasonable investment in only a few sensors in the water supply network.

Bankside groundwater is widely used as drinking water resource and, therefore, contamination has to be avoided. In the European Union groundwater protection is explicit subject to Water Framework Directive. While groundwater pollution may originate from different sources, this study investigated on impacts via flood events. Groundwater was sampled with increasing distance to the river Rhine near Karlsruhe, Germany. Samples were HPLC-MS-MS analyzed for the river contaminant carbamazepine to indicate river water infiltration, giving permanent presence in 250 m distance to the river (14-47 μg L⁻¹). Following a flood event, concentrations of about 16-20 μg L⁻¹ could also be detected in a distance of 750 m to the river. Furthermore, estrogenic activity as determined with the Yeast Estrogen Screen assay was determined to increase up to a 17β-ethinylestradiol equivalent concentration (E-EQ)=2.9 ng L⁻¹ near the river, while activity was initially measured following the flood with up to E-EQ=2.6 ng L⁻¹ in 750 m distance. Detections were delayed with increasing distance to the river indicating river water expansion into the aquifer. Flood suspended matter and floodplain soil were fractionated and analyzed for estrogenic activity in parallel giving up to 1.4 ng g⁻¹ and up to 0.7 ng g⁻¹, respectively. Target analysis focusing on known estrogenic active substances only explained < 1% of measured activities. Nevertheless, river water infiltration was shown deep into bankside groundwater, thus, impacting groundwater quality. Therefore, flood events have to be in the focus when aiming for groundwater and drinking water protection as well as for implementation of Water Framework Directive.

This study was carried out to determine hazards of particle-bound contaminants in rivers to retention areas close to public well fields in the context of flood events. The focus was on the assessment of soil contamination at a planned retention area. Soil core samples were chemically and biologically analyzed. Samples were fractionated to identify and compare contaminant loads and biological effects of soil and flood suspended particulate matter (SPM). Soil cores were sampled at inundated and non-inundated sites at a planned retention area. Soil was analyzed for hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs) as well as for polycyclic aromatic hydrocarbons (PAHs). The highest inducing soil sample was fractionated applying a recently developed automated fractionation method to receive further insight into contaminant loads in soil at inundated sites. Impacts on biological scale were assessed using in vitro biotests for xenometabolic activity (7-ethoxyresorufin-o-deethylase (EROD) assay) as well as for mutagenic activity (Ames fluctuation assay). EROD induction was calculated as biological equivalent concentration (bio-TEQ), and mutagenic potentials were given as no observed effect concentration (NOEC) and maximum induction factor (IFmax). Soil core samples of each site induced EROD activity. However, extracts of soil sampled at a ground swale was by far the highest inducing (topsoil bio-TEQ = 41,000 pg/g). Further, chemical analysis yielded relative increases in concentration in particular: HCB (0.05 mg/kg), PCBs (0.19 mg/kg), and EPA-PAHs (39 mg/kg). Extracts of soil samples caused no mutagenic effects. PAHs caused the bulk of EROD activity (bio-TEQ = 32,000 pg/g) with ground swale topsoil fractions. Further, fractions containing moderately polar and polar substances gave elevated effects (bio-TEQ = 8,200 pg/g). Mutagenic potentials were shown with most fractions. However, highest induction was observed with fractions containing moderately polar to polar substances reflected by a NOEC ≥0.03 mg/ml and an IFmax ≤29. Soil contamination at floodplains is heterogeneous but may reach elevated levels with soil swales giving highest chemical concentrations and biological effects with total sample extracts and fractions. The origin of floodplain soil contamination can be evaluated using lines of evidence which may result in identification of contaminant transport path from sediment, via flood SPM to soil. Taking hazard assessment of floodplain soil forward to risk evaluation may indicate a concern which highlights the need to further investigate on hazards caused by eroded sediment in flood events to avoid conflicts of interest when planning and operating retention basins.

The presented study investigated on contamination of suspended particulate matter (SPM) in rivers that was sampled long-term and with higher frequency during a flood event at the river Rhine. It was conducted to determine in vitro biological effects as well as to identify and quantify compound classes and effective contaminants. Research was part of investigation on hazards of contaminants bound to SPM to inundated sites and retention areas that are inundated during flood events. SPM was sampled in 2006 and more frequently in a flood event (August, 2007) at the river Rhine barrage of Iffezheim, Germany. SPM was GC-MS analyzed for hexachlorobenzene (HCB), several polychlorinated biphenyls (PCBs) as well as for polycyclic aromatic hydrocarbons (PAHs). Flood samples were fractionated applying a recently developed automated fractionation method to receive further insight into contaminant loads in flood SPM. Impacts on biological scale were assessed using in vitro biotests for xenometabolic 7-ethoxyresorufin-o-deethylase (EROD) assay as well as for mutagenic activity (Ames fluctuation assay). EROD induction was calculated as biological equivalent concentrations (bio-TEQs) and mutagenic potentials were shown as NOECs and maximum induction factors. Chemical analysis gave low concentrations of PCBs (2006 and 2007) and HCB (2006). HCB concentrations increased during the flood in 2007 (maximum, 110 µg/kg SPM). Concentrations of PCBs were only initially elevated in the flood (maximum, 67 µg/kg SPM). EROD induction bio-TEQs ranged from 1,160 to 6,640 pg/g SPM in 2006 and showed maximum bio-TEQ at the peak discharge in 2007. There was no mutagenic activity with SPM of both years. Fractionation indicated highest EROD induction in PAH fractions with prioritized (EPA-) PAHs contributing to less than 1% to the fractions total bio-TEQ but also fractions containing more polar-to-polar substances were shown to contribute minor. Furthermore, more polar fractions were mutagenic active with SPM sampled after the peak of discharge (IFmax = 14.7). Contaminants bound to flood SPM can be hazardous to inundated retention areas. Concentrations can be assumed to be increasing correlated with discharge and, thus, with more extreme flood events. Furthermore, biological effects are elevated or first place appearing with SPM from floods. Hazards have to be expected not only from persistent and non-polar substances but alike from less persistent and more polar ones that, furthermore, are more relevant evaluating hazards to drinking water resources from public well fields.

The essential processes and mechanisms of the transport of contaminants from a river to a well field via a flood water retention area are presented. The transport is conceptualized as a succession of three phases: (1) contaminant entry into the retention area, (2) passage through the soil zone and (3) transport with the groundwater flow. Depending on the conditions of a given location and on the properties of the contaminants of interest, processes within each transport phase may reduce the concentration of the contaminants at the well field. For the Kastenwoert-Rappenwoert study area, the results of the described processes are shown by chemical and ecotoxicological analyses as well as by numerical modelling. Based on the results of the analyses, it is predicted that some contaminants in the study area will be completely detained along the transport path, while others will be transported as far as the well field, although in significantly reduced concentrations.