Water is used by man for a variety of important purposes, among them irrigation, navigation, hydroelectric power generation, industrial manufacturing, waste disposal, recreation, and wildlife enhancement. The most fundamental use of all, however, is community water supply for immediate and vital needs-drinking, washing, cooking and sanitation.

At present anyone living in a developed country hardly gives thought to the availability of water for these needs. One has only to open a tap at any time of day or night to obtain as much clean water as desired. But often it is not realized that even in industrially advanced countries like the United States or Canada, running water in homes was not available in many rural areas a few decades ago-certainly within living memory. In many instances rural electrification was instrumental in providing running water. Read more

The energy and climate benefits of cool roofs have been well established: By reflecting rather than absorbing the sun’s energy, light-colored roofs keep buildings, cities, and even the entire planet cooler. Now a new study by the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) has found that cool roofs can also save water by reducing how much is needed for urban irrigation.

Based on regional climate simulations of 18 California counties, Berkeley Lab researchers Pouya Vahmani and Andrew Jones found that widespread cool roof adoption could reduce outdoor water consumption by as much as 9 percent. In Los Angeles County, total water savings could reach 83 million gallons per day, assuming all buildings had reflective roofs installed. Their study, “Water conservation benefits of urban heat mitigation,” was published in the journal Nature Communications. Read more

A global study has found a paradox: our water supplies are shrinking at the same time as climate change is generating more intense rain. And the culprit is the drying of soils, say researchers, pointing to a world where drought-like conditions will become the new normal, especially in regions that are already dry.

The study – the most exhaustive global analysis of rainfall and rivers – was conducted by a team led by Professor Ashish Sharma at Australia’s University of New South Wales (UNSW) in Sydney. It relied on actual data from 43,000 rainfall stations and 5,300 river monitoring sites in 160 countries, instead of basing its findings on model simulations of a future climate, which can be uncertain and at times questionable.

“This is something that has been missed,” said Sharma, an ARC Future Fellow at UNSW’s School of Civil and Environmental Engineering. “We expected rainfall to increase, since warmer air stores more moisture – and that is what climate models predicted too. What we did not expect is that, despite all the extra rain everywhere in the world, is that the large rivers are drying out. Read more

Average surface temperatures of the Black Sea may not have risen, according to the surprising results of a new study from the JRC.

The study used a model to simulate possible temperature changes and predict long term trends in the Black Sea’s hydrodynamics.

While the surface showed no long term warming trend, the same simulations also indicated that average temperatures at 50 metres below the surface may be rising.

The Black Sea has unique natural conditions like a positive net freshwater balance and very specific local currents. Observational data on temperature change is varied and scarce. As such it is not clear what the impacts of climate change have been on Black Sea water temperatures. Read more

Public water quality has received a lot of attention in recent years as some disturbing discoveries have been made regarding lead levels in cities across the country. Now, a new study from the Johns Hopkins University pinpoints other chemicals in water that are worth paying attention to – and in fact, some of them may be created, ironically, during the water treatment process itself.

To rid water of compounds that are known to be toxic, water treatment plants now often use methods to oxidize them, turning them into other, presumably less harmful chemicals called “transformation products.” Though earlier studies have looked at the byproducts of water treatment processes like chlorination, not so much is known about the products formed during some of the newer processes, like oxidation with hydrogen peroxide and UV light, which are especially relevant in water reuse. Read more