I have a 10x16 dock that I want to put on a river. Normally during storm surges the water depth changes about 5 feet. However, once or twice a year it can go to 20 feet with rapid water flow as the river is fairly narrow. Any good ideas (and cost effective - cheap) on how to best secure the dock? Putting pilings in the water isn't an option. Just about anything else is. A lot of people pull their docks out when they now the water is going to rise. Any help is appreciated.