A method for treating an aqueous fluid comprising a biodegradable organic substance in an installation comprising an upflow bioreactor containing a sludge bed, said sludge bed comprising biomass, an external separator, and a conditioning tank, the method comprising: treating the fluid in the conditioning tank; feeding the treated fluid into a lower part of the bioreactor and forming biogas; withdrawing the fluid from an upper part of the bioreactor, which withdrawn fluid comprises biomass; feeding the aqueous fluid withdrawn from the upper part of the bioreactor into the external separator wherein the aqueous fluid comprising the biomass is separated into a liquid phase, and a fluid phase enriched in biomass; returning said fluid phase enriched in biomass from the external separator to the bioreactor; and returning a part of said liquid phase to the conditioning tank.

Embodiments described herein are directed to methods and systems for treating wastewater or storm water using vermifiltration. The wastewater can come from various sources, such as agricultural sources, municipal and industrial sources, wineries, the dairy industry, and many others. The systems can include vermicomposting beds that are capable of removing high amounts of contaminants, pollutants, and/or toxic substances from wastewater. The wastewater may be applied to vermicomposting beds, for example, by an irrigation system. The irrigation system may provide, for example, improved bed coverage and more even saturation. The vermicomposting beds can remove various harmful substances from the wastewater, such as petroleum products; industrial chemicals; heavy metals (e.g., lead, mercury, cadmium, arsenic); pesticides (e.g., atrazine, chlorpyrifos); and organic compounds (e.g., phenols, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs)).

Provided herein are systems and methods for treating a wastewater stream. In one embodiment, a wastewater stream is treated using a settling tank, a membrane feed tank, and at least one filtration unit.