Water is fundamental to all aspects of life, the defining characteristic of our planet. 97.5% of all water is found in the oceans, of the remaining fresh water only 1% is accessible for extraction and use. Functioning, healthy aquatic ecosystems provide us with an extraordinary array of benefits: food, medicine, recreational services, coastal protection, treatment of our waste, and carbon sequestration. At the beginning of the 21st century, the world is facing a water crisis, both quantitative and qualitative, caused by continued population growth, industrialization, food production practices, rising living standards and poor water use strategies. Wastewater management, or lack thereof, has a direct impact on the biological diversity of aquatic ecosystems, compromising the fundamental integrity of our life support systems, on which a wide range of sectors, from urban development to food production, depend and to industry. It is essential that wastewater management is considered part of integrated, ecosystem-based management that works across sectors and boundaries, freshwater and marine. Wastewater, also written as sewage, is any water whose quality has been negatively affected by anthropogenic influence. It includes liquid waste discharged from domestic dwellings, commercial properties, industry and/or agriculture and can include a wide range of potential contaminants and concentrations. In most common usage, it refers to municipal wastewater that contains a broad spectrum of contaminants resulting from the mixing of wastewater from homes, businesses, industrial areas, and often storm drains, especially in older sewer systems. Municipal wastewater is usually treated in a combined sewer system, sanitary...... middle of paper......lly occurs in the late morning, when wastewater from the morning peak water use reaches the treatment plant, and a second peak flow usually occurs in the evening. The relative magnitude of the peaks and when they occur vary from country to country, depending on the size of the community and the length of the sewers. Small communities with small sewer systems have a much higher peak flow to average flow ratio than large communities. Although the magnitude of the peaks attenuates as the wastewater passes through a treatment plant, the daily variations in flow from a municipal treatment plant make it impractical in most cases to irrigate the effluent directly from the wastewater treatment plant. treatment plant. Some form of flow equalization or short-term storage of treated effluent is necessary to provide a relatively constant supply of reclaimed water for efficient irrigation.