The world’s reservoirs are shrinking, with as much as 1% of the freshwater being lost annually to silt buildup, further exacerbating water shortage problems, finds a book being touted by the United Nations Environment Programme. Reservoir storage loss already exceeds that to be gained from new dams under construction. The worldwide rate of loss could increase if current deforestation rates continue unchecked and global warming predictions come to pass, with heavier rainfall accelerating erosion rates. Various management techniques, such as “flushing,” which uses floodwaters to sweep debris out of downstream reservoirs, could help to restore some storage capacity, according to the book’s authors. Evacuation of Sediments from Reservoirs by Rodney White can be purchased at www.thomastelford.com. —KRIS CHRISTEN