Urban wet-weather discharges from combined sewer overflows (CSO) and stormwater outlets (SWO) are a potential pathway for micropollutants (trace contaminants) to surface waters, posing a threat to the environment and possible water reuse applications. Despite large efforts to monitor micropollutants in the last decade, the gained information is still limited and scattered. In a metastudy we performed a data-driven analysis of measurements collected at 77 sites (683 events, 297 detected micropollutants) over the last decade to investigate which micropollutants are most relevant in terms of 1) occurrence and 2) potential risk for the aquatic environment, 3) estimate the minimum number of data to be collected in monitoring studies to reliably obtain concentration estimates, and 4) provide recommendations for future monitoring campaigns. We highlight micropollutants to be prioritized due to their high occurrence and critical concentration levels compared to environmental quality standards. These top-listed micropollutants include contaminants from all chemical classes (pesticides, heavy metals, polycyclic aromatic hydrocarbons, personal care products, pharmaceuticals, and industrial and household chemicals). Analysis of over 30,000 event mean concentrations shows a large fraction of measurements (> 50%) were below the limit of quantification, stressing the need for reliable, standard monitoring procedures. High variability was observed among events and sites, with differences between micropollutant classes. The number of events required for a reliable estimate of site mean concentrations (error bandwidth of 1 around the “true" value) depends on the individual micropollutant. The median minimum number of events is 7 for CSO (2 to 31, 80%-interquantile) and 6 for SWO (1 to 25 events, 80%-interquantile). Our analysis indicates the minimum number of sites needed to assess global pollution levels and our data collection and analysis can be used to estimate the required number of sites for an urban catchment. Our data-driven analysis demonstrates how future wet-weather monitoring programs will be more effective if the consequences of high variability inherent in urban wet-weather discharges are considered.

Ultimate aims to establish and foster water smart industrial symbiosis by implementing circular economy solutions for water, material and energy recovery. The circular economy solutions shall create a win-win situation for both the water sector and the industry. In nine case studies the water sector forms those symbiosis with companies from the agro-food, beverage, petrochemical, chemical and biotech industry.

German: In den vergangenen Jahren hat sich die Datenlage zum Zustand der Abwasserkanalisation und zur Wirkung unterschiedlicher Sanierungsverfahren stetig verbessert. Basierend auf diesen Erkenntnissen wurden durch das Kompetenzzentrum Wasser Berlin und die Berliner Wasserbetriebe Prognosemodelle zur Bewertung unterschiedlicher Sanierungsszenarien sowie zur Lokalisierung schadhafter Kanäle entwickelt. Die vorliegende Studie zeigt den Weg von Bestands- und Zustandsdaten des Kanalnetzes zu einem an die lokalen Randbedingungen angepassten Simulationswerkzeug für die strategische Kanalsanierungsplanung. Dabei werden Methoden zur modellgestützten Ergänzung von Datenlücken sowie die entwickelten Modellkomponenten für Kanalalterung und -sanierung vorgestellt. Darüber hinaus werden Ergebnisse ausgewählter Sanierungsszenarien und die wichtigsten Prognoseunsicherheiten diskutiert. Der entwickelte Ansatz unterstützt die Kanalsanierungs- und Investitionsplanung von Kommunen und hilft, den Zustand der Abwasserinfrastruktur langfristig zu erhalten oder zu verbessern.

The main aim of this study was a survey of micropollutants in stormwater runoff of Berlin (Germany) and its dependence on land-use types. In a one-year monitoring program, event mean concentrations were measured for a set of 106 parameters, including 85 organic micropollutants (e.g., flame retardants, phthalates, pesticides/biocides, polycyclic aromatic hydrocarbons (PAH)), heavy metals and standard parameters. Monitoring points were selected in five catchments of different urban land-use types, and at one urban river. We detected 77 of the 106 parameters at least once in stormwater runoff of the investigated catchment types. On average, stormwater runoff con-tained a mix of 24 µg L-1 organic micropollutants and 1.3 mg L-1 heavy metals. For organic micropol-lutants, concentrations were highest in all catchments for the plasticizer diisodecyl phthalate. Concentrations of all but five parameters showed significant differences among the five land-use types. While major roads were the dominant source of traffic-related substances such as PAH, each of the other land-use types showed the highest concentrations for some substances (e.g., flame retardants in commercial area, pesticides in catchment dominated by one family homes). Comparison with environmental quality standards (EQS) for surface waters shows that 13 micropollutants in storm-water runoff and 8 micropollutants in the receiving river exceeded German quality standards for receiving surface waters during storm events, highlighting the relevance of stormwater inputs for urban surface waters. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

To sustain good harvests, each year more than one million tonnes of mineral phosphorus have to be imported to the European Union (van Dijk et al., unpublished data), while the potential to recover and recycle this essential resource remains untapped or is just inefficiently used as in the case of sewage sludge, manure and food waste. In recent years various technical solutions have been developed to recover phosphorus providing mineral compounds suitable as raw material for fertiliser production or even as ready-to-use fertiliser. Regarding the implementation of these technologies, operational benefits for plant operators like the water utilities in the case of P recovery from wastewater and/or sewage sludge are the strongest argument for their market penetration. Without the provision of direct operational benefits, implementation needs to be motivated or even enforced by suitable and reliable policies. In order to realise a circular economy, it is important not just to focus on the recovery itself. The recovered materials need to match the requirements and needs of their intended users. Therefore, full value-chain solutions have to be promoted instead of isolated technology-focused approaches. Following our principles of sustainability and resource efficiency, the assessment of innovations must also include their environmental impact. This review provides an overview of recently developed and promising technologies for phosphorus recovery from wastewater and discusses aspects regarding their wide-spread application, along with their limitations. It will focus on recovery and recycling from sewage sludge. Not only the technologies themselves, also the recovered materials and their valorisation options are addressed. Results of the EU FP7 funded project P-REX entitled 'Sustainable sewage sludge management fostering phosphorus recovery and energy efficiency' and other recent initiatives will be included. Since innovation always needs an enabling environment for market penetration, barriers set by the existing legal framework and measures to resolve them will be reviewed. Finally, Goethe's words are true more than ever: 'Knowing is not enough, we must apply! Willing is not enough, we must do!'

Weltweit stehen Kommunen vor der Aufgabe, Wassersysteme mittelfristig an neue Gegebenheiten anzupassen und sie resilienter gegen unvorhersehbare Ereignisse zu machen. Digitale Lösungen für das Abwasser- und Wassermanagement werden dafür immer bedeutsamer.

Die Rückgewinnung von Cellulose mit dem Cellvation-Prozess verbessert die Umweltbilanz einer Kläranlage (KA) und senkt ihren Ausstoß an Treibhausgasen um 15 %. Dies wird vor allem durch betriebliche Vorteile auf der KA wie Senkung des Stromverbrauchs für die Belüftung und weniger Überschussschlammproduktion erreicht. Darüber hinaus kann die rückgewonnene Cellulose (Recell*) als Strukturmaterial andere Rohstoffe in bestimmten Produktionsprozessen ersetzen. Im EU-Projekt SMART-Plant konnte neben der zuverlässigen Leistung des Cellvation-Prozesses auch der Umweltvorteil erfolgreich demonstriert werden.

Durch die Klärschlammverordnung (AbfKlärV) wird die Phosphor(P)-Rückgewinnung aus Klärschlämmen bzw. Klärschlammaschen für Klärwerke mit einer genehmigten Ausbaugröße ab 100.000 Einwohnerwerten (EW) ab dem Kalenderjahr 2029 gesetzlich vorgeschrieben. Dies betrifft alle sechs Klärwerke, welche von den Berliner Wasserbetrieben (BWB) betrieben werden. Die vorliegende Studie diskutiert verschiedene Möglichkeiten der Phosphorrückgewinnung mit Blick auf die Vorgaben der AbfKlärV, die Wirtschaftlichkeit der verschiedenen Ansätze und dient den BWB als Konzeptpapier für eine weitergehende Planung Ihrer Strategie zur P-Rückgewinnung.

The sewage sludge ordinance forces wastewater treatment plants to ensure the recovery of phosphate from the produced sewage sludge. In most cases, this obligation is transferred to the company in charge of the sludge disposal. For the recovery process, technology-specific but not product-specific specifications are made. The present article gives an overview of the products of different processes and their possible marketing in two routes: direct marketing and integration into the fertilizer industry. Possibilities, limits, requirements and potential product revenues for selected products are discussed against the background of current world market prices. Finally, the chemical expenditure of certain processes and logistical considerations are addressed. The considerations suggest that wet chemical ash processes should best be integrated in chemical parks.