Lake/river terrain

Anyone think a lake or river would be a good project.
Maybe a frozen lake with ice flows?
Ice crystals sticking up from the water?

I've seen some module ones, you could make it have some ice floes?

Issue I am having with the resin now is its tendency to get through small cracks and make a mess.
If I am to do a modular river section any ideas on both getting each section to match up and what I could do to keep the river matched up on the resin side without it spilling all over or looking silly?

clear acetate to cap ends of all rivers?