Quote:
Originally Posted by Dig68
Thanks JP. Last night I watched some videos on these dams and how people get caught up. Very scary. Your explanation was great. So one more question - are these dams and other dangers usually marked on the river so you know they are coming up or do you just have to know ahead of time?
|
Donna,
In my experience, I would say that in general there are no upstream warning signs for low head dams that lie ahead. There are exceptions. Sometimes there are warning buoys in the pool above the dam, large signs on the banks, or riverside park kiosks to locate a dam. Paddling guidebooks should indicate the location of dams. Talk to people who use the river regularly to learn about dams and other hazards. Someone else might want to weigh in here with their experience and opinion.
Recognizing the presence of a dam while paddling downstream is something gained from experience. Look for the water to form a horizontal line across the river as the telltale sign. You may be able to hear a dam as well, but rapids also make noise, so sound is not the best indicator. But there are variations in how dams are constructed so that the horizontal line may be interrupted. This is the case with the Struthers dam on the Mahoning. It is constructed in segments so that the horizontal line is interrupted by pillars rising above the water at regular intervals.
Natural rock ledges can also form horizontal lines across all or part of a river and have their own hydraulics that act just like those below low head dams. The strength of these hydraulics is generally less than that of a low head dam in my experience, but some can still be sticky if you get sideways. We don't run into many of these on the rivers that our club paddles as best as I can recall, although someone else might want to chime in here.
It's great that you're doing your homework. Hope this helps.
jp