As a homebuilder in Ohio, we are running into the same situation as far as the new treated lumber. You can use bolts only if they are 1/2" dia. otherwise you will have to use double dipped fasteners. With the price of steel going thru the roof and lumber at an all time high, I would look into a floating dock system if I were in your situation. If that is not an option, they make screw in type pilings that I have heard of. Not familiar with them though. There was a post on it a few months ago. good luck