5/8 minus (rough gravel with dirt mixed in), wheelbarrow, shovel
The watering troughs each have a drain hole. That makes it very easy to drain and clean the ponds. If they sit flat on a level surface, you’ll be left with standing water in the bottom. I set my troughs on a slope to allow as much water as possible to drain out when I remove the plug. Fill/dig as needed to get the right angle for the troughs to drain well.
Once you have your site an acceptable angle, find your boulders. We have them in abundance around here, so this part was easy. Boulders don’t always sit how you want them to, so don’t be overly fussy about this; there’s “ideal” and there’s “good enough.” The rocks I used are much too large to move by hand; tractors are very handy. I removed the watering troughs to have maneuvering room when we were positioning the rocks, then replaced the troughs after all the rocks were in place. I left small openings on the low side to allow access to the drain plugs.
At this point I took a shortcut and eye-balled where level would be. Don’t do that. Put water in your troughs up to your desired water level and mark a line all the way around. Drain the water out. Saw the top off the troughs. Use a file to remove the burrs.
At this stage, I filled in the gaps between the trough and the rocks with gravel. Another time, I’d wait until the ponds were full to do this step. I also used the gravel to build an entrance ramp so the ducks would have access to the water.
Even if the water starts out level with the top of the pond, ducks will splash some of the water out. Ducks, believe it or not, can drown. Put a rock in the pond near the entrance/exit so they have a place to stand/sit and rest before attempting to climb out.
$20 for the saw
$40 for two yards of 5/8 minus (one yard would have been enough)
boulders – free
watering troughs – free because they were cracked at the top and the neighbor donated them if I’d haul them away