New tech offers solution to regional wastewater crisis
19th November 2020 - Source: Myanmar Times
Today, November 19, is World Toilet Day, which might not sound like the most exciting of international commemorations, but the annual event does highlight one of the more immediate and pressing concerns faced by the region, and the planet.
The reality is that around 780 million Asians are forced to defecate in the open, and approximately 80 percent of wastewater across the region is returned to the environment untreated. These raw numbers have very real implications.
According to UNICEF, 12pc of schools in the East Asia and Pacific region have no drinking water facilities and 32pc have no sanitation facilities. Healthcare centres across the region are also drastically short of appropriate sanitation services.
These issues have a disastrous impact at both the personal and community levels. Education is heavily affected, and girls, especially those who are menstruating, tend to avoid school as a result of inadequate toilet facilities.
Public health also suffers, as children, with less immunity to disease than adults, are forced to bathe in and drink contaminated water, often as a result of poorly managed, or nonexistent, wastewater treatment. Thousands of children get ill and die every day from faecal-oral diseases, including, potentially, COVID-19. Often fatal illnesses like these are easily avoided when clean sanitation solutions are available.
These figures also indicate the problem is far from being solved.
Explosive regional growth
Clearly, governments, the private sector and civil society, despite some progress, are struggling to get ahead of the explosive economic and social growth in the region, and the wastewater dilemma caused by such growth.
Often, the solutions take the form of centralised or reticulated sewage systems. However, such big-ticket options and lack of access to appropriate wastewater treatment tend to marginalise two important groups in Asia: regional communities outside urban areas, and lower socio-economic communities within urban populations.
Decentralised wastewater treatment systems have been increasingly used in areas without access to central sewage plants. Systems such as pit latrines, compost toilets and septic tanks have been widely used.
Many of these systems tend to focus on removing or containing the effluent rather than treating it so it can be safely dispersed back into the environment. They often require considerable energy to run properly and need servicing by trained operators. In many cases, they are not sustainable.
Old ideas no longer viable
Where treatment systems do exist, they are often old-style aerated treatment technology, known as AWTS. The basic problems with these are that they use chemicals that can be dangerous and are failure-prone if misused. Also, they require electricity, have a relatively high failure rate, are not scalable, are vulnerable to natural disasters, and need servicing by trained personnel.
Such treatment problems can be addressed by existing technology, using more environmentally sustainable and cost-effective approaches. Different treatment systems, such as various forms of passive wastewater treatment technology, can be applied effectively to wastewater problem areas, such as those noted above, treating wastewater to advanced secondary standard.
As we enter the third decade of this century, it is time to reconsider our approach to vital issues like wastewater treatment. Old technology may no longer be considered a viable solution. Clearly, in broad terms, it isn't working. The proof is written in the daily tragedy of lives lost to, and in the many communities held back by, poor sanitation and limited hygiene facilities.
Perhaps on this World Toilet Day, and with the UN's sixth sustainable development goal in sight, we in Asia can embark on a new, flexible, cost-effective and sustainable water sanitation and hygiene journey that isn't bound by old ideas but is invigorated by fresh thinking.
Ian Christesen is a consultant for passive wastewater technology and a director of the National On-Site Providers Association in Australia.