Shifting from sanitation to environmental protection
Water engineering originates from the need of urban societies for safe and healthy water and prevention of waterborne diseases.
As a result of engineers from over a century ago, waterborne diseases have been mostly eradicated from society in industrialised societies.
At universities most sanitary engineering departments have been renamed in the past 50 years into environmental engineering, reflecting the shift in attention from sanitation to environmental protection.
New processes introduced in the wastewater sector are evaluated based on their capacity to reduce nutrients, recover resources or minimise energy demands. However, pathogen removal efficiency hardly plays a role.
Sewage monitoring as a pandemic ‘dashboard’
The Covid-19 pandemic has put the relation between wastewater and health back in the centre of attention.
Worldwide, many wastewater and health researchers have started to monitor sewage for the presence of corona viruses to monitor the spread of Covid-19 in society.
"In the Netherlands, sewage monitoring is part of the governmental ‘dashboard’ used to monitor the pandemic."
In countries such as the Netherlands, sewage monitoring is part of the governmental 'dashboard' used to monitor the pandemic. As an indication of research to date, from July, a total of 213 scientific publications have been reviewed and published related to Covid-19 and wastewater.
While it seems that this is a new area for wastewater research, in 2010 there was already a peak in scientific publications on coronaviruses, although mainly from Asia. Furthermore, wastewater monitoring for the spread of diseases such as polio is regularly practised and documented in the past.
Measuring antibiotic resistance and pharmaceuticals is performed recently, but mainly placed in the context of preventing pollution and hardly in the context of public health monitoring.
Will the attention for wastewater as a reflection of public health remain once the pandemic fades away, or will environmental engineering departments change their name back to sanitary and health engineering?
A dose of realism on Covid-19 testing in wastewater
Current data suggests that coronavirus testing in sewage is being used as an early warning for diseases.
However, with samples analysed in early 2020, doctors were not fully responsive to Covid-19 as a potential cause of symptoms of their patients.
"As usually after the initial enthusiasm, there will likely be disappointment that promises of wastewater testing are not as large as initially assumed."
As usually after initial enthusiasm, there will likely be disappointment that promises of wastewater testing are not as large as initially assumed.
Hopefully, this will be followed by realism. The large-scale current testing and data gathering might bridge the gap between urban drainage and sewage engineering and the field of public health and epidemiology.
The technology to detect viruses and microorganisms is very sensitive, as well as the technique to detect pharmaceuticals.
Let’s use the Covid-19 experience to seek long-term collaboration between sewage specialists, health specialists and epidemiologists to fully exploit the potential of wastewater as a reflection of public health in a society.
Mark van Loosdrecht
Delft University of Technology