Corps Dredging Season Ends on Middle Mississippi River; Multi-year Drought Predicted
The Corps completed an extended dredging season, and in February started bringing in equipment in for seasonal maintenance and leave for the crew. The Corps Dredges
Hurley and Potter completed dredging operations on the Middle Mississippi the last week of January. The dustpan dredges have been operating well beyond the normal dredging season, which usually ends in early December. The Potter mobilized the first week of July, and has worked throughout the 300 miles of Mississippi River in St. Louis District’s area of responsibility. The Hurley came up river from the Corps’ Memphis District in December and has been dredging between Thebes and Chester, Illinois, and also supported the rock removal efforts at Thebes by removing sand that had accumulated over the rock pinnacles.
The Corps dredged more than eight million cubic yards of sediment along the Middle Mississippi River in the last six months – more than twice the amount dredged during an average, non-drought year. And yet, as a result of river engineering work, this was only half the amount dredged during the drought of 1988-89.
The Corps’ large dustpan dredges remain critical in maintaining a reliable channel for commerce, especially in low water. Restrictions to industry traffic were limited to safety operations during blasting and other rock removal work and not a result of channel availability. There were no groundings within the channel in the fall and winter during this low water period.
The Corps will continue to monitor crossings, points on the river where the flow of water slows down, allowing suspended sediment to drop out and create a sandbar. The Potter will be the dredge to respond to any "just-in-time" dredging needs, should the sediment patterns change with fluctuating river levels.
Rock removal work continues at Grand Tower and Thebes, Illinois, as conditions permit. With recent rains, river levels have risen to a point that contractors have temporarily suspended work. Rock removal will resume as river levels fall.
The Mississippi River Valley and the Missouri River Basin are experiencing a drought equal to or worse than any of the past five decades, the St. Louis District reported on its website. Weather forecasters predict that this may be the first year of a multi-year drought situation.
One of the impacts of the drought is that it has reduced how much water is flowing in these river systems. One of the missions Congress has given the Corps is to maintain a channel for navigation on the river nine feet deep and 300 feet wide.
On the Middle Mississippi River between St. Louis and Cairo, Illinois, where the Ohio River joins the Mississippi, the St. Louis District is combining years of innovative engineering, around-the-clock dredging, and rock removal to keep commerce moving on the open river despite record lows.
The U.S. Coast Guard is also working closely with the Corps and industry to ensure the safety and security of vessels and mariners as they transit through affected navigable waterways and their tributaries. Despite the low water conditions, commerce has continued to flow effectively, with only minor interruptions and delays and no major safety or environmental incidents on the rivers. The Corps said this is a direct result of the close coordination between government and industry.