The secondary effluent of Berlin's sewage treatment plant Ruhleben was oxidized by dosages of 2.5-22 mg/L ozone and varying operation conditions to remove pharmaceutical compounds and disinfect water in parallel. The majority of analysed neutral and acidic drugs were efficiently removed to the detection limit at ozone consumptions equal to a dosage of < 10 mg/L O3. However, certain compounds like clofibric acid, ketaprofen and traced metabolites required higher dosages of > 10-15 mg/LO3 for complete removal. A series of four iodinated organic contrast media (ICM) persisted the ozone treatment even at high consumption rates. Related to disinfection, the legal requirements (EU bathing water directive) could be fulfilled by a consumption of < 10 mg/L O3. For a combined oxidation by ozone and H2O2 (perozone) higher conversion rates for clofibric acid, naproxen and ketaprofen could be obtained at lower dosage (6 mg/L O3). For two ICM, namely iopamidol and iohexol, this was the case at higher ozone consumption. The removal of adsorbable organic iodine (AOI) > 10% could not be achieved by any treatment. The initial genotoxicity of the secondary effluent was stated by four independent tests. Due to the application of ozone, this genotoxicity was completely removed. The presented results confirm that ozonation can be a suitable advanced wastewater treatment at varying operation conditions to lower effluent concentrations of pharmaceuticals and active micro-organsisms.

This paper presents the results on the occurrence and fate of antibiotic residues during bankfiltration obtained from a study carried out in terms of an interdisciplinary project at three transects in Berlin, Germany. Six antibiotic compounds and two metabolites were detected at ng/L concentrations in water samples from the lakes or in the monitoring wells of the transects. Clarithromycin, roxithromycin (macrolide), trimethoprim (synergist for sulfonamides) and acetyl-sulfamethoxazole (metabolite) are efficiently removed by bank filtration. Residues of clindamycin (lincosamid) and dehydro-erythromycin (metabolite) were completely attenuated during the soil passage. For sulfamethoxazole (sulfonamide), a significant but not complete removal during bank filtration was observed. It was the only compound that could be detected at tracelevels in samples collected from water-supply wells.

Investigations on the behavior of different bulk organics and trace organic compounds at a bank filtration site at Lake Tegel in Berlin, Germany, and in a long retention soil column system are reported. Objective of the research was to assess important factors of influence for the degradation of bulk and trace organics. More than two years of monitoring for the bulk parameter DOC proved that the redox conditions significantly influence the DOC-degradation kinetic but not necessarily the residual concentration. LC-OCD measurements confirmed that the change in character is comparable for aerobic and anoxic/anaerobic infiltration. Only the fraction of polysaccharides shows a better removal under aerobic conditions. Furthermore, adsorbable organic iodine (AOI) measurements revealed a more efficient degradation of AOI and AOBr under anoxic/anaerobic conditions. The monitoring of the single organic pollutants Iopromide, Sulfamethoxazole and naphthalenedisulfonic acids showed that the redox conditions have an influence on the degradation behavior of some of the monitored compounds. Iopromide was efficiently removed at all times, but no evidence for a dehalogenation under oxic conditions was found. Sulfamethoxazole showed a better removal under anoxic/anaerobic conditions. The very stable 1.5naphthalenesulfonic acid was not removed under either redox conditions.

In Berlin gibt es nur noch wenige abgelegene kleine Einzugsgebiete (<1%), die nicht an das zentrale Abwassersystem angeschlossen sind. Aber in den neuen EU-Ländern ist der Anteil an der Bevölkerung, die nicht an eine zentrale Abwasserreinigung angeschlossen sind, noch deutlich höher. Besonders in dünn besiedelten Gebieten gibt es immer noch sehr viele Abwassersammelgruben (abflusslos oder mit Versickerung). Für empfindliche Einzugsgebiete (Badeseen, Wassersport, Fremdenverkehr) könnte für die Einleitung von gereinigtem Abwasser eine über die Mindestanforderung in der Abwasserverordnung hinausgehende weitergehende Nährstoffentfernung von der zuständigen Behörde gefordert werden. Das Membranbelebungsverfahren (MBR) könnte eine technische und auch wirtschaftliche Lösung bieten, um eine semi-zentrale Erschließung in Gebieten mit einem sensitiven Vorfluter (Gewässer) zu realisieren. Mittels eines Membranprozesses kann die vollständige Desinfektion und weitgehende biologische Phosphorentfernung bis auf 0.1mgP/L oder niedriger ohne Fällmittel erreicht werden (Gnirss et al., 2003a, Gnirss et al., 2003b). Damit kann der Standard der EU-Richtlinie für Badegewässer direkt im Ablauf der kleinen Kläranlage erreicht werden und die Eutrophierung im Oberflächenge-wässer reduziert werden. Die Umsetzung von MBR-Anlagen in kleinen oder mittleren Einzugsgebieten ist mittels schlüsselfertiger Containereinheiten möglich, wodurch die Investitionskosten gesenkt und die üblichen Unannehmlichkeiten von Kläranlagen wie Geruchs- und Lärmemissionen vermieden werden können. Dieser Artikel stellt die Vorteile und die Kosten der MBRTechnologie für die dezentrale Erschließung eines Siedlungsgebietes im Norden von Berlin vor und vergleicht sie mit dem konventionellen Verfahren. Dabei werden die technischen Grundlagen der Demonstrationsanlage ausführlich erläutert, und die wichtigsten Designkriterien für die MBR-Anlage und das Druckentwässerungsnetz vorgestellt.

Given the important cost reduction of the membrane bioreactor technology in the last years, this advanced treatment process has now become cost-competitive with other conventional technologies. A cost estimation analysis undertaken with few remaining unsewered and remote areas of Berlin showed that the implementation of semi-central sanitation scheme with a local membrane bioreactor plant would lead to similar costs than the connection to the central sewer, but with a superior effluent quality. For such small systems, some design issues have to be considered in order to optimise the costs and the operation regime, such as plant capacity increase, buffer capacity, process configuration and membrane flux.

Real-time control of urban drainage systems allows activating capacities of storm water storage and wastewater treatment that were not used before. The historically developed structure of the Berlin combined sewerage, along with its aforementioned properties, allows per se a systematic management of the sub-systems. In the course of rehabilitation works the implementation of local regulators already opened additional storage reserves. Additionally, the potential of global control concepts for sewerage, pump stations and treatment plants is studied within the framework of the project “Integrated Sewage Management” to increase the systems efficiency. Especially, a coordination of the currently locally controlled pump stations entails a reduction of sewer overflows and hence an enhanced protection of the environment. For the catchment of wwtp Berlin-Ruhleben an integrated model of the collection system, pump stations, pressurised mains and the wwtp itself has been built up in order to evaluate different scenarios of global pump station control in comparison to a local control scenario (reference). Special attention was paid to the discharges from CSOs. Due to the high dynamic of these events and the high fraction of biodegradable organic substrate within the effluents, the impact on the water body over this path plays an important role. Concerning CSOs a maximum reduction of 14 % (COD load) and 20 % (TKN load) could be achieved. In conclusion it can be stated that a reduction of total emissions from the sewage system can be achieved by operating the pump stations in a global control mode. Furthermore, the main improvement can be observed for the discharges from combined sewer overflows.

Residues of pharmaceuticals used in human medical care have recently been detected as important trace contaminants of sewage, surface and groundwater. This paper compiles the recent state of knowledge on the occurrence and fate of pharmaceutical residues in the aquatic environment of urban areas. Findings in sewage effluents, surface, ground, and drinking water at concentrations up to the µg/L-level have been reported and will be discussed to demonstrate the impact of pharmaceutical residues on the aquatic environment and on public water supply. The efficiency of natural and technological processes such as bank filtration or membrane filtration for the removal of pharmaceutical residues including estrogenic steroids, analgesics, antibiotics, anti-epileptic drugs, blood lipid regulators, and several drug metabolites will be presented and discussed.