A new report from the European Environment Agency (EEA) underscores that urban wastewater treatment now must also address additional challenges brought on by climate changes, increasing populations and, importantly, new pollutants.
The 9 October briefing suggests solutions for “Urban Waste Water Treatment for 21st Century Challenges”.
According to EEA about 97 percent of households in western and central Europe are connected to treatment facilities compared with 70 percent in southern and southeastern Europe. Despite marked improvement in recent years, it is estimated that approximately 30 million people in Europe are still not connected to waste water treatment plants, with a significant proportion in rural areas.
Climate change is presenting heavier and more frequent rainfall, affecting the ability of urban storm water sewers to operate efficiently. Excessive rain can overwhelm the systems and lead to overflows. A lack of rainfall leads to problems in collection and treatment of sewage.
It is incumbent on local authorities and water utilities to address these challenges through new construction, additional maintenance, operational efficiency and upgrades. Sourcing and retaining skilled staff to deliver the improvement is crucial to success of the improvements in water treatment systems.
The EEA briefing also examines the effect of antibiotics and other excreted pharmaceuticals that are increasingly being found in wastewater. A “cocktail” mix of chemicals cannot be easily tackled by many treatment plants, as they require costly, more stringent and energy-intensive treatment techniques.
The EEA suggests that scarce resources and high energy costs should promote efforts to make the wastewater treatment process more efficient. More can be done to recycle and reuse water and to recover materials during the treatment cycle.
The briefing cites some examples of investments already being taken across Europe to improve waste water treatment resilience, with the use of retention ponds and rainfall reservoirs to manage water flows from flash floods, or in reusing water that has been treated and cleaned.
Key “take-aways” include:
- Proper collection and treatment of urban wastewater is essential to protect human health and the environment
- No one solution fits all. European urban wastewater treatment plants function in widely varying conditions, ranging from different substances, population being served and local climatic conditions.
- New pressures such as adapting to climate change, providing facilities in urban and rural areas, and tackling newly identified pollutants all require substantial investment in addition to maintaining existing infrastructure.
- More needs to be done to insure greater recycling, reuse, and material removal.