1 . A new study by scientists at Utrecht University concludes that about half of global wastewater is treated, rather than the previous estimate of 20%. Despite this promising finding, the authors warn that treatment rates in developing countries are still very low.
Humans and factories produce vast quantities of wastewater per day. If not properly collected and treated, wastewater may severely threaten human health and pollute the environment.
The authors use national statistics to estimate volumes of wastewater production, collection, treatment and reuse. “Globally, about 359 billion cubic metres of wastewater is produced each year, equivalent to 144 million Olympic-sized swimming pools,” says Edward Jones, PhD researcher at Utrecht University. “About 48 percent of that water is currently released untreated. This is much lower than the frequently announced figure of 80%.”
While the results show a more optimistic outlook, the authors stress that many challenges still exist. “We see that particularly in the developing world, where most of the future population growth will likely occur, treatment rates are falling behind,” Jones explains. “In these countries, wastewater production is likely to rise at a faster pace than the current development of collection and treatment basic facilities. This poses serious threats to both human health and the environment.”
The main problem, especially in the developing world, is the lack of financial resources to build basic facilities to collect and treat wastewater. This is particularly the case for advanced treatment technologies, which can be extremely expensive. However, the authors highlight potential opportunities for creative reuse of wastewater streams that could help to finance improved wastewater treatment practices.
“The most obvious reuse of treated wastewater is to increase freshwater water supplies,” Jones states. Treated wastewater reuse is already an important source of irrigation water in many dry countries. However, only 11% of the wastewater produced globally is currently being reused, which shows large opportunities for expansion.
“But freshwater increasing is not the only opportunity,” says Jones. “Wastewater also has large potential as a source of nutrients and energy. Recognition of wastewater as a resource, opposed to as ‘waste’, will be the key to driving improved treatment going forward.”
However, the authors stress the importance of proper monitoring of wastewater treatment factories, accompanied by strong legislation (法律) and regulations, to ensure that the reuse of wastewater is safe. The authors also acknowledge public acceptance as another key barrier towards increasing wastewater reuse.
1. According to the author, the meaning of treating wastewater lies in ________.| A．encouraging new scientific findings |
| B．estimating volumes of wastewater production |
| C．ensuring human health and protecting the environment |
| D．measuring how much wastewater is produced globally per day |
| A．equal | B．harmful | C．useful | D．friendly |
| A．treated wastewater can’t be used as irrigation water |
| B．wastewater production in developing countries is falling |
| C．the treatment of wastewater is more serious than estimated |
| D．public recognition plays an important role in wastewater reuse |
