• California's San Joaquin Valley still sinking

    Since the 1920s, excessive pumping of groundwater at thousands of wells in California’s San Joaquin Valley has caused land in sections of the valley to subside, or sink, by as much as 28 feet (8.5 meters). This subsidence is exacerbated during droughts, when farmers rely heavily on groundwater to sustain one of the most productive agricultural regions in the nation. Long-term subsidence is a serious and challenging concern for California’s water managers, putting state and federal aqueducts, levees, bridges, and roads at risk of damage. Already, land subsidence has damaged thousands of public and private groundwater wells throughout the San Joaquin Valley. Furthermore, the subsidence can permanently reduce the storage capacity of underground aquifers, threatening future water supplies.

  • Mountain snowpack melt more slowly in a warming world

    As the world warms, mountain snowpack will not only melt earlier, it will also melt more slowly, according to a new study by scientists at the National Center for Atmospheric Research (NCAR). The counterintuitive finding could have widespread implications for water supplies, ecosystem health, and flood risk.

  • As climate warms, Colorado River flows will keep shrinking

    Warming in the twenty-first century reduced Colorado River flows by at least 0.5 million acre-feet, about the amount of water used by two million people for one year. From 2000 to 2014, the river’s flows declined to only 81 percent of the twentieth-century average, a reduction of about 2.9 million acre-feet of water per year. One acre-foot of water will serve a family of four for one year, according to the U.S. Bureau of Reclamation. From one-sixth to one-half of the twenty-first-century reduction in flow can be attributed to the higher temperatures since 2000. As temperature continues to increase with climate change, Colorado River flows will continue to decline.

  • Snow science in support of U.S. water supply

    More than one-sixth of the world’s population relies on seasonal snow for water. In the western U.S., nearly three-quarters of the annual streamflow that provides the water supply arrives as spring and summer melt from the mountain snow packs. Right now, predictions of streamflow can vary widely due to limited ground measurement sites. This is one of the reasons scientists and resource managers are interested in a comprehensive view from space of what they call snow-water equivalent — the amount of liquid water contained in snow cover. Scientists use snow-water equivalent to estimate the amount of water that will melt into mountain streams, rivers and reservoirs.

  • Genetic tool improves arsenic studies

    Arsenic-contaminated drinking water impacts millions of people worldwide. Groundwater contamination is primarily caused by microbes that convert one form of arsenic into another form that can infiltrate groundwater. Researchers developed a genetic tool that makes it easier to identify which microbial species have the arsenic-converting genes.

  • Storms filled 37 percent of California snow-water deficit

    The “atmospheric river” weather patterns that pummeled California with storms from late December to late January may have recouped 37 percent of the state’s five-year snow-water deficit. Researchers estimate that two powerful recent storms deposited roughly 17.5-million acre feet (21.6 cubic kilometers) of water on California’s Sierra Nevada range in January. Compared to averages from the pre-drought satellite record, that amount represents more than 120 percent of the typical annual snow accumulation for this range.

  • “Solar vapor” device purifies dirty drinking water

    A new way to make nasty or salty water drinkable features carbon-dipped paper. It could be a cheap and efficient option for addressing global drinking water shortages, particularly in developing areas and regions affected by natural disasters.

  • Israel recycles 90% of its wastewater, four times more than any other country

    Almost 90 percent of Israeli wastewater is purified and used in irrigation, making it an undisputed world leader in this field. Spain, the second-place country, recycles 20 percent of its wastewater, compared to Israel’s 87 percent. Israel is also a pioneer in desalination, operating Sorek — the world’s largest seawater desalination plant — which employs advanced technologies, allowing it to produce a thousand liters of drinking water for 58 U.S. cents.

  • Detailed look at decentralized water systems

    The “decentralized” water system at the Center for Sustainable Landscapes (CSL) at Phipps Conservatory and Botanical Gardens, which treats all non-potable water on site, contributes to the net-zero building’s recognition as one of the greenest buildings in the world. However, research into the efficacy of these systems versus traditional treatment is practically non-existent in the literature. Thanks to a collaboration between Phipps and the University of Pittsburgh’s Swanson School of Engineering, researchers now have a greater understanding of the life cycle of water reuse systems designed for living buildings, from construction through day-to-day use.

  • Stopping human-made droughts and floods before they start

    Alberta’s rivers are a main source of water for irrigated agriculture in Canada’s Prairie provinces. But climate change and increased human interference mean that the flow of these headwaters is under threat. This could have major implications for Canadian gross domestic product, and even global food security.

  • What caused the Flint water crisis

    Flint, Michigan, continues to grapple with the public health crisis that unfolded as lead levels in its tap water spiked to alarming levels. Now the scientists who helped uncover the crisis have tested galvanized iron pipes extracted from the “ground zero” house. They confirm that the lead that had accumulated on the interior surface of the pipes was the most likely source of the lead contamination.

  • Salt on the earth

    When ice and snow melt away into streams and groundwater, road salt goes with it. The Pennsylvania Department of Transportation is mindful of its salt use: It applies nearly 27,500 tons of salt every year to 779 miles of Erie County roads, including highways. Researchers have developed a map that shows elevated concentrations of salt along Trout Run, which flows into Fourmile Creek, which empties into Lake Erie, the primary source of drinking water for the 280,000 residents of Erie County.

  • Affordable water in the U.S.: A looming crisis

    If water rates continue rising at projected amounts, the number of U.S. households unable to afford water could triple in five years, to nearly 36 percent, a new study finds. A variety of factors, ranging from aging infrastructure to climate change to population decline in urban areas, are making residents’ ability to afford water and wastewater services a burgeoning crisis.

  • Changing rainfall patterns linked to water security in India

    Changing rainfall is the key factor driving changes in groundwater storage in India, according to a new study. The study shows that changing monsoon patterns—which are tied to higher temperatures in the Indian Ocean—are an even greater driver of change in groundwater storage than the pumping of groundwater for agriculture.

  • Groundwater resources around the world could be depleted by 2050s

    Human consumption could deplete groundwater in parts of India, southern Europe, and the United States in the coming decades, according to new research presented at the 2016 American Geophysical Union Fall Meeting. New modeling of the world’s groundwater levels finds aquifers — the soil or porous rocks that hold groundwater — in the Upper Ganges Basin area of India, southern Spain, and Italy could be depleted between 2040 and 2060.