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To employ technologies that sustainably harvest resources from wastewater (for example struvite granules shown here), new perceptions and infrastructure planning and design processes are required.Water and wastewater system decisions have been traditionally driven by considerations of function, safety, and cost-benefit analysis. The emphasis on costs and benefits would be acceptable if all relevant factors could be included in the analysis, but unfortunately many relevant factors are routinely excluded. Coupled with failures to fully engage the public in decision-making processes, this can impede progress toward achieving sustainable solutions. Ignoring broader social issues that impact the adoption of sustainable solutions prolongs not only global environmental and ecological problems, but also unjust public health and social conditions in the developing world.Within the water and wastewater management industry, discussions of sustainable development have often focused on water stress (1, 2): a hazard that is exacerbated by other global stressors such as climate change, demographic and land use changes, increasing population, and urbanization (2). In addition to water stress, water and wastewater management practices contribute to nutrient imbalances and a host of environmental detriments such as eutrophication (3), discharge of pharmaceuticals and other emerging contaminants (4), and a loss of biodiversity in receiving streams (5). Efforts to address these issues across regional and global scales are hindered by the historical disconnect between the water quality and water quantity factions of the water profession. Although our understanding of sustainability is constantly evolving, the water and wastewater design process retains its foundation in engineering traditions established in the early 20th century (6). As we chart a path in the 21st century, we contend that wastewater contains resources worthy of recovering and that the development of

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The objective of this study was to evaluate emerging anaerobic membrane bioreactor (AnMBR) technology in comparison with conventional wastewater energy recovery technologies. Wastewater treatment process modeling and systems analyses were combined to evaluate the conditions under which AnMBR may produce more net energy and have lower life cycle environmental emissions than high rate activated sludge with anaerobic digestion (HRAS+AD), conventional activated sludge with anaerobic digestion (CAS+AD), and an aerobic membrane bioreactor with anaerobic digestion (AeMBR+AD). For medium strength domestic wastewater treatment under baseline assumptions at 15 °C, AnMBR recovered 49% more energy as biogas than HRAS+AD, the most energy positive conventional technology considered, but had significantly higher energy demands and environmental emissions. Global warming impacts associated with AnMBR were largely due to emissions of effluent dissolved methane. For high strength domestic wastewater treatment, AnMBR recovered 15% more net energy than HRAS+AD, and the environmental emissions gap between the two systems was reduced. Future developments of AnMBR technology in low energy fouling control, increased flux, and management of effluent methane emissions would make AnMBR competitive with HRAS+AD. Rapid advancements in AnMBR technology must continue to achieve its full economic and environmental potential as an energy recovery strategy for domestic wastewater.

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The estrogen receptor agonist fate of hexane extracts from various locations and phases (liquid and solid) within one pilot-scale and two full-scale wastewater treatment facilities were examined by use of the receptor-binding yeast estrogen screen (YES assay). Estrogenic activity was found in samples that contained a high concentration of biological solids and was particularly high in the suspended solid fraction from biosolids treatment facilities. Mass balances revealed that the estrogenic activity associated with the processed biosolids constituted between 5 and 10% of the influent estrogenic activity, while the treated liquid effluent prior to disinfection contained between 26 and 43%. Overall, this suggests that between 51 and 67% of the estrogenic activity contained in the influent wastewater was either biodegraded during the wastewater or biosolids treatment processes or was unavailable to the extraction/detection procedure. In both aerobic and anaerobic digestion, mass balances revealed an increase in estrogenic activity as treatment progressed and biosolids destruction occurred. The estrogenic activity associated with the solid phase decreased during mesophilic aerobic digestion. A correlation was observed between the estrogenicity of mixed liquor suspended solids and aerobic sludge age and suggests that wastewater treatment facilities can be designed and operated to enhance the sorption and removal of estrogenic compounds from the liquid phase.

The biological fate of 17α-ethinylestradiol (EE2; 500 ng/L to 1 mg/L) and trimethoprim (TMP; 1 μg/L to 1 mg/L) was evaluated with flow through reactors containing an ammonia oxidizing bacterial (AOB) culture, two enriched heterotrophic cultures devoid of nitrifier activity, and nitrifying activated sludge (NAS) cultures. AOBs biotransformed EE2 but not TMP, whereas heterotrophs mineralized EE2, biotransformed TMP, and mineralized EE2-derived metabolites generated by AOBs. Kinetic bioassays showed that AOBs biotransformed EE2 five times faster than heterotrophs. The basal expression of heterotrophic dioxygenase enzymes was sufficient to achieve the high degree of transformation observed at EE2 and TMP concentrations ≤ 1 mg/L, and enhanced enzyme expression was not necessary. The importance of AOBs in removing EE2 and TMP was evaluated further by performing NAS experiments at lower feed concentrations (500-1000 ng/L). EE2 removal slowed markedly after AOBs were inhibited, while TMP removal was not affected by AOB inhibition. Two key EE2 metabolites formed by AOB and heterotrophic laboratory-scale chemostats were also found in independent laboratory-scale mixed culture bioreactors; one of these, sulfo-EE2, was largely resistant to further biodegradation. AOBs and heterotrophs may cooperatively enhance the reliability of treatment systems where efficient removal of EE2 is desired.

Sorption coefficients (K(COC)) between 17beta-estradiol (E2), 17alpha-ethinylestradiol (EE2) and size-fractionated colloidal organic carbon (COC) derived from two biological wastewater treatment facilities were quantified by fluorescence quenching. The two wastewater treatment systems included a full-scale activated sludge system (FSAS) and a membrane bioreactor (MBR). The K(COC) coefficients were highly variable and ranged between (<1 to 179) x 10(3) L/kgCOC for E2 and (<1 to 430) x 10(3) L/kgCOC for EE2 and were higher than expected from the analytes octanol-water partition coefficient. Correlations between the molar extinction coefficients measured at 280 nm (e280) and K(COC) coefficients were weak but stronger for E2 compared to EE2. Attempts at correlating sorption behavior with colloidal protein and polysaccharide concentrations were only marginally successful (r2 approximately 0.4). These low correlations suggest that aromatic content, protein, or polysaccharide concentration can not adequately explain E2 and EE2 sorption behavior to COC and that other fractions of the organic matter pool play an important role in binding. A substantial portion of the aqueous E2 and EE2 concentrations (up to 60%) may be associated with colloidal material, suggesting that COC may play a role in the fate and transport of E2 and EE2 during the activated sludge process.