Highlights in Wastewater History, 1950s-2020s

Highlights in Wastewater History, 1950s-2020s

Through the late 19^th and early 20^th centuries, the wastewater industry pushed through its infancy. Industrialized countries across the globe were experimenting with settling tanks and mechanical aeration, using activated sludge and microbes for biological filtration, and planning infrastructure with sewers and treatment plants.

Then came the Golden Age of Wastewater – a time when innovations abounded thanks to the start of government regulation in the industry. Continue reading to see how historic laws and ordinances shaped the way the world looks at wastewater today.     

1. Federal Water Pollution Control Act: In 1948, the US government passed the Federal Water Pollution Control Act (FWPCA). It was the first major US law to address water pollution, providing technical and financial assistance to states but without many federally mandated goals or limits. Globally, secondary treatment systems designed to prevent eutrophication and disease also began to make their appearance.
2. US Clean Water Act: To strengthen the FWPCA, legislators passed sweeping amendments to the act in 1972, effectively creating the modern Clean Water Act. It made it unlawful to discharge a pollutant into US waters without a permit, granted the Environmental Protection Agency power to implement pollution control programs and set standards for wastewater, maintained the requirement to set water quality standards for all contaminants in surface waters, and funded the construction of sewage treatment plants through grants. It has been further amended and continues to face challenges.
3. Rise of Environmental Movements – and Ideas: The formation of Greenpeace, founded in 1971, and other environmental groups underscored concern about clean water and treated wastewater. Public interest and government intervention brought about new advanced treatment methods, tertiary filtration, phosphorus removal via chemicals, activated carbon for absorption of odors, chlorination for disinfection, and more. By the end of the 1970s, wastewater treatment plants were viewed as essential civic infrastructure.    
4. SBRs and SCADA: In the 1980s, innovation pressed on – this time, with sequencing batch reactors (SBRs) and supervisory control and data acquisition (SCADA) software/hardware. An SBR is a process that treats wastewater in batches in a single tank to perform all treatment steps. SCADA systems evolved along with digital technology advancements. They monitor and control industrial processes, enabling workers to manage operations, like wastewater treatment, from a central location. Both are still in use today.
5. Advancements Continue: From the end of the 20^th century to today, advancements in wastewater management, treatment, and resource recovery continue with technologies like membrane bioreactors, anaerobic contact processes, and upflow anaerobic sludge blankets. In the 1990s, biological nutrient removal systems (BNRs) came on the scene using microorganisms in different oxygen zones to remove excess nitrogen and phosphorus from wastewater. Other advancements from before the turn of the century include ultraviolet disinfection, energy efficiency, sludge management, and water reuse.

So, what does the future of wastewater treatment look like? A peek into our crystal ball reveals several developments, including influence from artificial intelligence, wider adoption of membrane bioreactors, new ways to handle microplastics and “forever” per- and polyfluoroalkyl substances (PFAS), and the concept of recovering resources from wastewater.

We’ll see what else the future has in store for us!