When shore fishing or fishing from a fishing pier/dock, how do you determine the depth you will be fishing at? When in the boat, I like to use slip bobbers, how can I use these while fishing from a pier or shore?

Just keep adjusting your slip bobber till you find bottom then fish the desired depth.

I use a ice fishing depth bomb. then it hits bottom hard then adjust slip knot.

Just the opposite of using slip bobber you use a slip through sinker method. Tie bobber to tail end. When you cast out, just let out line until bobber floats. Crank down and guestimate how many reel handle turns equals line retrieve and just figure that as depth. Drag sinker and bobber closer and repeat bobber release by feed it some line. Repeat method and you map out the bottom contour.

I use a my hummingbird "smart cast" to prescan looking for structure/baitfish and to determine the exact debth of each spot as well as the debth that the fish are holding at. (smart cast is a remote tranducer that sends info to the fishfinder screen ,they make smakker watch sized unites that cost about 50 bucks. I have the largest version of smartcast, its sceen is avarage sized and has a backlighted screen and costed $140.

There is a (BOBBER WITH A BRAIN) that works good for shore fishing you cast it and it sets the depth with a bait above the weight method they are inexpensive. I use them often. Use THOSE words on a web auction site to find them.