We were able to spot some of them when the conditions calmed down, seems odd they would purposely create such a hazard. The Missouri river also has similar dams, but they are well above the water except for very high water conditions, and NO ONE boats when those conditions are present. From what I found out, it differs due to the currents involved. The Miss runs a bit slower, so they are longer to create enough flow to "gouge" the channel, but under to deal with high water conditions without dramatically increasing flow rate. At least that what's a local COE guy suggested. Bought a weld on skeg online yesterday for roughly $25.00, when it arrives, it will be time to tear down the lower half. Was considering adding a nose cone, but cant seem to locate one for an Alpha. The very nose of the drive took a pretty good gouge, so I need to do something in that area, just filling and smoothing seems a bit plain considering I will already be there welding. From what I've read it will take some time, you must be cautious about too much heat in the housing deforming the thrust bearing area. Might just have to post some pics on this project since I've not seen this issue covered before on this forum.