How do you think "river rock" got in the river?

It depends on how big the rocks are, how strong the runoff is and how steep the grade is.

Thanks lazygardens. I guess It is just common sense. There is only a slight grade, but the water has moved some of my smaller logs that line the paths. I think I will just go out and watch in the next hard rain.

Logs float, and water will lift and move it a lot easier than stones or rocks. My brother and I built a bridge over a ditch for our mom to drive her lawn mower over instead of going out on the road between properties. It was built out of two 12 foot telephone poles ( 12 inches diameter) and twenty five 2" by 8" by 6 feet nailed to the poles. Last heavy rain (we got 4 inches in an hour!) floated the bridge 100 feet away. (luckily, before the water went down, we were able to "raft" it back into position and tie it down!) Now, larger stones or rocks (five inches across or more) probably might have shifted, but would not have floated away(:

NoNews, I have a creek that I had built a couple of years ago.
It has a liner over a sand bottom and is covered with flat river rock.
The water run off comes fast and furious during a heavy rain.
It has washed the sand out and shifted the rocks but the
bridge has never moved. However, the water does get out of
the creek bed and washes the mulch out of the path to the lake.
The rocks get washed off the sides and pile up in the creek
bed. We intend on getting the creek below the bridge made
deeper and wider and trying to slow the run off down some.
It gets old putting the rocks back in place.

Good luck with your project, if you get the heavier river
rock they probably wouldn't wash out. I wish we had.

Jan

Jan, thanks for your thoughts. How steep is your grade? My grade is just bearly distinguishable. This week, it rained about an inch, so I went out to watch. The water did not flow, but just soaked into the ground.
I think I am going to try to combine some plants along side the flow area. I have been checking on 'rain garden' on GW. I would rather have the rain water my yard, than flow off into the creek as run off.
Thanks again. Nancy