Why the World's Rivers Are Losing Sediment and Why It ...
Jun 20, 2017 · Why the World's Rivers Are Losing Sediment and Why It Matters. Vast amounts of riverborne sediment are trapped behind the world's large dams, depriving areas downstream of material that is badly needed to build up the marshes and wetlands that act as a buffer against rising seas. In September 2011, after 20 years of planning, workers began ...