The effects of anthropogenic activities on water resources are large and extensive, and these effects are reflected in terms of physical changes to the environment. Water security is considered as the chief goal of water management in a broader aspect. Therefore, the present chapter highlights the major challenges for sustainable water management that need to be considered to address water security issues. Water quality has an important role in the development of the socioeconomic sphere of society. Among the different wastewater treatment technologies developed to tackle with the ever degrading water quality, bio-based treatment technologies are the most promising ones. In contrary to conventional treatment techniques, phycoremediation is considered to have enormous commercial potential by achieving economic and renewable sources for bioenergy production. Biological methods utilize microorganisms to eliminate contaminants present in wastewater, and these methods become sustainable when they produce some valuable products such as biofuels or bioactive compounds and can be used as a source of energy generation and can optimize the reuse and recycling of waste materials. In this way, by focusing on the sustainable development goal (SDG) 6, the problem of water security can be resolved and can be connected with other SDGs to form an integrated dynamic approach for sustainable water management.