Oh man! I sure do find tons of anchors on the river. Oddly enough; most of them are not wedged or hung up. Most of them are found in open areas with not obstructions.
I would never anchor with the river spilling. I think you could really get yourself hurt or sink your boat. I know of several flipped boat accidents already this past Winter.
I think the mushroom anchors work the best on one-two generators. Note; not in holding position but, in just slowing your drift hand letting them drag.
The forked anchors (river anchors) will always find a nice shoal to get hung on and they are easily lost.
I personally like using my chain-ball on the river in most conditions. However; I have lost one due to a pulley failure.
There is a simple technique to help retrieve stuck anchors. It involves wrapping a piece of rope around the base(bottom) of the anchor so that it can be leverage from the bottom up to reverse pull it from its stuck position. Run the tag end of the rope up the side of the anchor and feed a folded strand of the rope through the anchor top. Use some electrical tape and tape the rope around the anchor side. Make a folded knot on the initial side of the anchor mount to attach the main anchor rope.
The idea is that if you get hung; you can pull up hard and tear the tape. The rope will pull out of the anchor hole and pull tight to the bottom mounting position and allow you to retrieve the anchor from the bottom.
Also; another tip is to make an arrester in one end of the rope to act as a shock absorber in fast current. This simply involves folding your anchor rope and wrapping twine or tape around it to hold in normal use. In case of a hang; it will tear the binding and release the extra line to cushion the snag.
Here is a picture of one I made for a friend.
*Also; if you lose your anchor and need a new one-send me an email and I should be able to hook you up with a one I have found. Free of course!
**Here is a link to an excellent website about river anchoring. He also has tons of great fishing and boating information. http://www.sschapterpsa.com/ramblings/Anchoring.htm