(CNN) -- An 11-mile stretch of the Mississippi River near Greenville, Mississippi, was closed Monday to most vessel traffic because of low water levels, idling nearly a hundred boats and barges in the stream, according to the U.S. Coast Guard.

"We are allowing a limited number of vessels based on size" to attempt to pass, said New Orleans-based Coast Guard spokesman Ryan Tippets, adding that the closure was affecting 97 vessels Monday afternoon and was halting both northbound and southbound traffic.

Salt creeping up the Mississippi River

This same area near Greenville, which sees about 50 vessels pass on an average day, has been closed "intermittently" since August 12, when a vessel ran aground, said Tippets.

The Coast Guard and the Army Corps of Engineers have continued surveying the area and deemed it "dangerous for vessels to travel through," he said. The Army Corps of Engineers also has being dredging in the area to deepen the channel and help navigation.

Complete coverage of the drought

A historic drought and excessive heat have reduced water levels and scorched wide sections of the U.S. Midwest. Flooding last year may have worsened the situation on the Mississippi by leaving deposits of silt and debris in areas that would normally be clear.

Tippiets said he was unsure when the river would reopen or, once that happens, how long it would take to undo the gridlock.

Interactive map: Watch drought overtake U.S.

Are you affected by the drought? Let us know on CNN iReport.

1. What is going on near Greenville, Mississippi?
2. What are the consequences of the drought?
3. Where?
4. What body of water?
5. Who is responsible for closing the area?
6. What are they doing about it?
7. How many vessels are affected?
8. Who is Ryan Tippets?
9. What did he say?
10. Did a drought happen last year?
11. How did floods contribute to the problem?
1. A historic drought
2. vessel traffic is closte to hundred boats and barges
3. near Greenville, Mississippi
4. the Mississippi River
5. The Coast Guard and the Army Corps of Engineers
6. allowing a limited number of vessels based on size" to attempt to pass and dredging in the area to deepen the channel
7. hundreds it depends on the time and day
8. A New Orleans-based Coast Guard spokesman
9. he was unsure when the river would reopen or, once that happens, how long it would take to undo the gridlock.
10. yes
11. leaving deposits of silt and debris in areas that would normally be clear.