That's not evidence. Fossils, for example, can be interpreted to be arranged hydrologically by the flood. It depends on the assumptions.
Okay, this really gets on my nerves because I major in geology.
So here is a quick lesson on water and water movement. (This is gonna be long, skip if you don't want to learn/read or as just too lazy what ever floats your boat! no pun intended )
Competence: The largest rock the method of movement can carry. ie, Glaciers have high competence while rivers have a medium to low competence. Wind has low competence.
Capacity: The amount of material a moving body can carry. ie, Glacier have medium to low capacity, rivers have medium to high and wind has low capacity.
Strata: layers of rock accumulated over a certain time period.
Graded Beds: a special type of deposition in which the largest rocks are deposited at the bottom and the smallest at the top, usually happens when water is covering a large area and is slowly either evaporated or retreated from that area.
Bed load: the amount of rock at the bottom of the river that is being moved, usually by dragging or rolling
Suspended load: the amount of rock that is being carried by the river due to the river's velocity.
Solution or dissolved load: the chemical composition in the river that allows the river to "absorb" the sediment and carry it where it will be deposited due to another chemical change in the water. (think of this as dissolving salt in water, then evapourating the water and you'll be left with the salt again)
Bed: bottom of the river
Settling velocity: the lowest velocity in which the river can hold a certain sized rock.
Okay, so, let's "assume" that the fossils were deposited by the flood.
Firstly, from the Bible, it rained for 40 days and 40 nights.(PLEASE CORRECT ME IF I'M WRONG) What I'm getting out of that is that the water level just rose. So when the water level rises, the animals die.
So now we have dead things in the water, except for fish and such. The ability for the water to move the dead animals is very little as the water level just rose. So we have calm water that isn't moving that has flooded the earth. This means we should see the animals settle out around where they died for the big animals. The big animals would be like the bed load. The smaller animals would settle out where ever the current takes them. This would mean that you would see graded beds for your sedimentary rocks all around the world and "graded beds" for your fossils as well. This means largest animals would be found at the bottom of your sedimentary deposits and smallest on top. This is not the case as we know there are smaller fossils in the Cambrian Era than in the Jurassic.
But wait, what if it wasn't rain. It could be a massive flash flood. Okay, granted, that's how some of you think the Grand Canyon was form. Alright, let's have a crack at this one shall we?
Firstly, the largest animals would be moved as well, maybe not far but still moved some distance. Relatively, this would correlate to where the large animals are deposited. The smaller animals would have been deposited where the water slowed downs, below the settling velocity. This would mean we would find all the small animals to be deposited in one area. Which is not the case. We find small fossils throughout the place.
Secondly, the amount of erosion from a flash flood can not create something like the grand canyon. A flash flood almost always travels in a straight line from where it starts to the nearest base level (sea level).
Water erodes and deposits in different areas depending on how quickly the water is moving, at what elevation the water is moving and what the chemical composition of the water is.
Water flows differently depending on the slope of the land. It down-cuts if it is pretty high above sea level and downcutting is decreases as you get closer and closer to the base level. If it is at base level, a river tends to meander, and this allows geographic features like ox bow lakes and point bars and many more.
What does this have to do with a flood? well, relatively, a flash flood behaves similarly to the beginning of a river up in the mountains or at least elevated above sea level. They are fast, erodes quickly and are relatively straight assuming the material they're cutting through is the same and has not joints of areas of weakness.
While a flood produced by just rise in sea level behaves relatively like the meandering of a river, slow moving water and relatively stable.
Of course this is like quick, simple over view and there's a lot more to it, but you guys get the idea.