If you live in North America, you've probably never given the cost of water a second thought. In fact, you've probably taken its value for granted probably because it costs very little or because it's vastly abundant. 

In places like Saudi Arabia, however, a liter of water costs five times as much as a liter of gasoline. This is because much of the water in Saudi Arabia is seawater that is purified in desalinization plants (Al Jubail desalination plant shown above). This price relative to fuel is quite different in the United States. For example, a liter of water (from a tap) is virtually free, while a liter of gasoline is around $0.75 (about $3.00 per gallon). 

As a result of this significant difference in cost, it plays a major effect on hu ...

A new study that's challenging the popular idea that we should drink eight glasses of water a day for health purposes shows that a 'swallowing inhibition' is activated by the brain after excess liquid is consumed. This inhibition mechanism helps maintain tightly calibrated volumes of water in the body.

The lead scientist has pointed out that if we just do what our body demands us to, we'll probably get it right. In other words, it is the best practice to just drink according to thirst rather than an elaborate schedule.

Building on a previous study, the researchers asked participants to rate the amount of effort required to swallow water under two conditions; following exercise when they were thirsty and later after they were persuaded to drin ...

To tap into scarce water supplies, most desert plants have extensive root systems that burrow deep or spread wide. But one desert moss has a different trick up its sleeve: a thirst-quenching structure called an awn. Awns are tiny, hairlike structures that project from the end of each leaf to capture water (above). For the first time, scientists have examined in detail how this moss (Syntrichia caninervis) pulls water right from the air using its awns. At the smallest scale, the awns are covered with grooves about 100 nanometers deep and 200 nanometers wide, the perfect size for dew to condense within them when conditions are right. Those nanogrooves lie within larger troughs that measure about 1.5 micrometers deep and 3 micrometers wide, a ...

Some bugs, such as water scorpions, long-toed water beetle and predaceous diving beetles (shown below) use the molecular properties of water to create miniature scuba diving tanks and spacesuits. The cohesive forces between water molecules essentially makes water molecules "stick" together, allowing bubbles to form against a wall of tension. These little insects are small enough to take advantage of this, by trapping a bubble in their outer wings or tiny bristles on their shell.

...

There’s so much trash floating in some parts of the ocean that each square kilometer of surface water there holds almost 600,000 pieces of debris. Indeed, because there's so much of it, by 2050 birds of almost every ocean-foraging species may be eating plastic.

The AquaDom is a 25 m (82 ft) tall cylindrical acrylic glass aquarium built at the Radisson Blu Hotel in Berlin, Germany. You can ride the transparent elevator it has in the center!

Ever seen an egg cracked underwater?