Since then they have put in more than 2, 500 days of voluntary work, moving an estimated 300, 000 tonnes of mud from the route of the canal and its locks.

BBC: Barge on a canal

So extensive were the wet-season mudslides that in some years more mud and rock fell back into the canal than had been taken out in the first place.

ECONOMIST: The Panama Canal

The French had spent many years and thousands of lives trying to build a canal to connect the Atlantic and Pacific oceans and had been defeated by year-round heavy rains in mountainous mud, deadly diseases, and impossible expenses.

FORBES: The Panama Canal: When the U.S. Flexes Its Creative Muscle

The area remained an unnavigable bog, forcing traders to drag their boats through the mud until 1848, when William Butler Ogden, the mightiest industrialist in the Midwest, backed the first canal that allowed boat traffic to sail straight through.

FORBES: A most unromantic river