A host of new technologies and techniques for wastewater management are being developed around the world, in response to environmental, economic and societal limitations increasingly posed by conventional wastewater systems.

New approaches incorporate natural processes and are designed with sustainability in mind, in contrast to energy-intensive and chemical-dependent ystems in current use. The following overview is not meant to be exhaustive in describing these new approaches, but should give some idea of the diversity, flexibility and utility of these technologies.