Dredging

Mounting research blames a confluence of rising sea levels driven by global warming and the damming and dredging of key rivers and their tributaries for the rapid sinking and shrinking of Asia's seven major delta systems, from the Indus in Pakistan to the Pearl in China.

Dredging, pollution and overharvesting led to the disappearance of the oysters decades ago.

Dredging is a fishing method in which a dredge is dragged across the sea floor, either scraping or penetrating the bottom.

At Lake Gatun — created 100 years ago to supply water for the canal — Captain Ubaldo Pimentel has been running a passenger boat for decades. He says engineers are using dredging ships and dynamite to create deeper, wider passageways to the new Gatun locks.

To create living reefs, the state of Maryland hired the only shell dredging operation left in the country to dig up old oyster shells mired meters deep under Bay mud and silt.

Soundings showed wide variations in depths of water, and from the dredgings of the bottom came new types of sediment […]