When the Mississippi River's sediment-laden waters empty into the Gulf of Mexico, we are not only losing a tremendous opportunity to rebuild the wetlands using the river's natural land-building, we are also incurring millions of dollars of lost shipping revenue because of clogged riverways.  This article from the New Orleans Times Picayune (Feb. 10, 2016) explains how sediment clogging Southwest Pass can cause ships to have to offload up to five feet of height to make it through:

"Typically, the numbers we've heard is about $1 million per foot per ship," said Matt Gresham, a spokesman for the Port of New Orleans, about the losses caused by having to carry less cargo.

Some ships are having to "lighter," move some cargo off the ship in smaller boats to make the ship's draft less than 41 feet before entering the river, a costly practice. In other cases, including ships loading upriver, shipping companies are being notified of the restrictions and will load less cargo, officials said."

Read the full article.