Sustainable water and wastewater management might be a step closer with the help of nano-based technologies. Efficient monitoring and treatment options offered by nano-based systems offer a game-changing way to manage water and wastewater in a sustainable manner. To ensure that future generations have access to clean drinking water, it is essential to tackle current obstacles and encourage the ethical application of nanotechnology so that we may fully utilize its potential. Transparency, accuracy, and privacy protection must be ensured by legal frameworks that adapt to the usage of modern technologies. The use of nanosensors in the continuous monitoring of water quality is crucial. These sensors can identify pollutants at incredibly low concentrations because of their great sensitivity and selectivity. Examples of such membranes include carbon nanotube and graphene oxide membranes. Efficient removal of contaminants and recovery of resources are two examples of the improved treatment possibilities offered by nanomaterials. Nanomaterials provide unique legal issues in water treatment due to concerns over regulation, liability, and approval. In order to weigh the pros and cons of nano-based treatment approaches, laws should require thorough environmental impact evaluations. To guarantee the secure implementation of these technologies, further laws could be required. If there are any negative side effects from using nanosolutions to treat water and wastewater, the legal frameworks should spell out who is responsible. To deal with unanticipated outcomes, accountability mechanisms need to be set up. Ethical questions about the potential effects on human health, the environment, and society and the economy may arise in relation to water technologies based on nanotechnology. Responsible innovation and use can only be fostered if there are legal safeguards in place to deal with ethical concerns. Cooperation between nations is crucial in addressing water-related issues since they affect the entire world. In order to promote cooperation on nanosolutions, legal frameworks and agreements need to be in place to safeguard national rules while also promoting the exchange of information. Responsible and sustainable practices need addressing the legal problems that come with integrating nanotechnologies into water and wastewater management. Innovation can only flourish in an atmosphere where people’s health, the environment, and shared values are protected by dynamic regulatory frameworks. This review delves into the various ways nanotechnology is being used in water management, from monitoring to treatment. It also gives a quick rundown of the policy surrounding the use of nanosolutions for sustainable water and wastewater management, particularly in monitoring and treatment.