GUTTENBERG, Iowa – The Army Corps will close the navigation lock at its 90-year-old Dam 10 at Guttenberg to replace all four gates. This will be on four dates — 7 a.m. to 7 p.m. on August 13, 15, 20 and 22. Both towboat operators and recreational boaters were asked not to get in the way: Don’t tie up on the guide walls.
