Water - or rather, the lack of it - is a major global problem.
Just last month, United Nations Secretary-General Ban Ki Moon warned that the world may run out of fresh water, while a coalition of international water researchers, the Global Water Systems Project, warned that climate change, agriculture and water-intensive energy will put pressure on the world's freshwater supply.
But tiny Singapore, an island state with few natural water resources of its own, has come up with a solution that just might help other countries tap into ways to supply H2O.
It involves the "yuck" factor - what you flush down the toilet, and the run-off factories send down their drains.
The Government has come up with a way to specially treat and purify sewage and wastewater using advanced membrane technology. The result is water you can drink or can be used for industry, which may have once been water molecules that you sent gurgling down a bathroom drain.
The treated used water has been in use for 10 years now, with people overcoming their initial reluctance thanks to campaigns by public agencies which focused on the urgent need for water and how the water is treated, rather than its murky origins.
It is known in Singapore as Newater, a name dreamed up by the then chairman of the PUB water agency, Mr Lee Ek Tieng, as sexy and marketable, instead of say, Highly Purified Water and High- grade Industrial Water.
People certainly stomach it now - production capacity has increased nearly eightfold, from 15 million gallons a day to 117 million gallons a day, helping put Singapore on track to achieve near self-sufficiency in water.
By 2060, Newater is expected to meet up to 55 per cent of Singapore's water needs, which are projected to double from the current 400 million gallons a day to almost 800 million gallons. Desalination will be able to supply another 25 per cent of demand, and reservoirs and imported water the remainder.
This is quite something for the 700 sq km island, which had long relied on surface run-off from rain as well as water purchased and piped in from Malaysia, which it gets under a treaty that expires in 2061.
Click photo or here for an interactive graphic showing where used water goes.
From used to clean
To create Newater, used water is treated three times, with most of the result going to industrial cooling, or to industries that require very pure water.
Two to 3 per cent - depending on how dry the weather is - is mixed in with water in the country's reservoirs, which is treated and turned into drinking water.
First, the water undergoes microfiltration, where it is pushed through hollow fibre tubes with pores that trap particles and bacteria.
Next, water molecules are pushed through a membrane that weeds out smaller contaminants like organic compounds and viruses, in a process called reverse osmosis.
Finally, the water is disinfected with ultraviolet light that kills microbes that have slipped through.
At the end, chemicals are added to the water to restore its pH balance, while the by-products that remain are mixed with treated effluent and discharged.
The solution came after decades of research. Over that time, the cost of treatment technology came down and the technology also improved to use less energy. That made purifying wastewater to such high standards more cost-effective.
PUB's deputy director of technology, Mr Puah Aik Num, says: "All along, we had the idea to use every drop more than once. We also studied desalination in the 1990s, but that was very expensive. Membranes used half the energy that desalination did, and the economics changed."
The success of Newater could go beyond Singapore's shores, as water increasingly becomes a big business across the globe.
In 2006, Singapore's Government began to put serious money - S$470 million at last count - into growing its local environment and water industry, doubling the number of water firms to 100. Today, it has attracted companies from around the globe and sent home-grown firms out to the world.
Israeli water treatment firm Desalitech is testing a new desalination method at a Newater plant, while Singapore's Flagship Ecosystems has built a centralised effluent treatment plant in the Bangladeshi capital of Dhaka.
The success of Newater, however, has not only been about the success of membrane technology. Community and corporate efforts also played a big role, in helping the country push the idea that reclaimed water was safe to drink.
While home-grown companies such as water treatment firm Hyflux helped promote the Newater brand to the world and other companies got on board to produce hundreds of thousands of bottles for sale, grassroots and community leaders played a critical role at home.
At national celebrations and cultural festivals, they led the way in making it a point to drink Newater in public, to show confidence in the reclaimed water, while grassroots groups took pains to include bottles of it in goodie bags or serve them at mass events.
As one taxi driver put it: "I will drink it as long as it's clean. If I drink it often enough, I'll get used to it."
Click here for an interactive graphic showing where used water goes.