Almost all of the world’s wastewater is untreated. The United Nations recently released a major report on World Water Day, in which it finds that recycling wastewater would relieve global water shortages, while at the same time protecting the environment.
Irina Bokova, the director general of UNESCO, one of several UN organizations behind the report, stated that she finds that neglecting the opportunities arising from improved wastewater treatment technologies nothing less than unthinkable.
People have been using fresh water faster than nature can replace it for decades. This contributes to disease, hunger, migration and conflict in some regions. More than 66% of the world’s population currently live in zones that experience water scarcity at least one month per year, with 50% of those people living in India and China.
Water crises was identified as the top global risk over the next decade in the World Economic Forum’s annual survey of opinion leaders last year. The UN Environment Program forecasts that, based on current trends, water demand for energy, industry, and a further billion people will increase by 50% by 2030.
Droughts have already intensified in many areas due to global warming and, Earth will continue to get hotter in the course of the century, even with optimistic scenarios.
Benedito Braga, the head of the World Water Council, an umbrella grouping of governments, research bodies and associations, believes that in order to overcome the challenges brought on by human influence and climate change, it is essential to increase water security.
Wastewater, runoff from industry, agriculture and expanding cities, is a major portion of the problem, especially in developing countries. This is especially true in poor nations where very little, if any, wastewater is recycled or treated.
In high-income nations, approximately 70% of the wastewater generated is treated. This number drops to 38% in upper middle-income countries. Only eight percent of municipal and industrial wastewater is treated in low-income nations.
Nearly one million people die every year because of not being able to wash their hands properly and contaminated drinking water.
Nearly 3.5 million lives are lost to water related diseases per year in Asia, Africa and Latin America. This is more than the worldwide death toll from car crashes and AIDS together. Nutrients and chemicals from farms and factories seep into aquifers and create dead zones in lakes, rivers and coastal waters.
Richard Connor of UNESCO’s World Water Assessment Program and lead author notes that the 200 page long World Water Development Report proposed a four-pronged approach to transform wastewater from being a problem to becoming a solution.
The report concludes that apart from decreasing pollution at the source, policy initiatives need to shift focus to reusing water, eliminating pollutants from wastewater flows and recuperating by-products that could be re-used.
Connor told reporters that policy makers have mainly focused on providing clean water up to now, rather than managing it after it has been used. He added that the two aspects are inseparably linked, as water can be used repeatedly. Connor also pointed out that water from several main rivers in the U.S. is recycled up to 20 times before it reaches the ocean.
Astronauts on the International Space Station probably set the best example demonstrating the potential for reusing liquid waste by using recycled urine to wash up, and drinking it. On a bigger scale, many nations have spawned innovative technologies through sheer necessity.
Recycled water is already used for drinking by residents of the southern California coastal city of San Diego, and Singapore. According to the report, 90% and 50% of agricultural water is being recovered for reuse in Jordan and Israel respectively.
Guy Ryder, chair of UN-Water and head of the International Labor Organization noted that apart from being recycled, wastewater could also be a rich source of energy, minerals and nutrients. All of these can be extracted cost effectively. He added that ironically, these same elements cause appalling damage when untreated wastewater is dumped into the environment.
Wastewater’s nutrient load can for example be reduced by phosphorus being harvested from urine supplied by urine diverting toilets. These systems are already in use in China, Japan and Australia, and can be scaled up easily. A recent study demonstrated that if human urine and feces were to be recycled, more than 20% of the worldwide phosphorus demand would be met.
Waste can also be converted into fuel. A law passed in Japan in 2015 obliges sewage operators to use bio-solids as a form of energy that is carbon neutral. In the city of Osaka alone, 6,500 tons of fuel is produced annually from 43,000 tons of wet sewage sludge. This fuel is used to generate electricity.