The flood and winter ice damage has caused a few Yellowstone River areas to be closed by the MTFWP.
MAYORS LANDING to SHEEP MOUNTAIN access is closed until repairs can be completed. The train bridge and boat ramp at the RT. 89 access site are in severe and dangerous condition. The train bridge has the potential to fall into the river. The recently repaired boat ramp, on the downriver side of the bridge also needs work due to erosion from the recent flooding.
You can still take your boat out at Mayors Landing, near Livingston, but can’t launch from this site. Sheep’s Mountain access site is still open for launching as are the sites downriver. Shuttle companies are up to speed with current conditions and closures. 
MALLARD’S REST Access and campground are also closed indefinitely. The access road has eroded so bad that it is gradually falling back into the river. A new road and access to the campground is required. Ice damage and the recent flood are to blame. You cannot launch or take out at this site. 
It is always a good idea to check out the launch and take out points before you do any drifts or floats. Fortunately, there are other nearby access sites that will allow continued usage. Your drifts will take longer. Also consider that 10–13-mile drifts are about the maximum for a full day of fishing or recreation.
Float, Drift, and Fish safely!
Montana Grant