Hi Amanda –
the problem with the drum is that in order to de-chlorinate the water it needs sunlight so the drum would need to be clear or opaque. However, here is what Dr. Bones (a real MD says about it/pool water) in this case so safe for humans to drink:
“If you are stuck without water after a hurricane or other event, but have a swimming pool nearby that’s full of water, can you drink from it? The answer is no, pool water contains lots of chlorine; but there’s a simple way to dechlorinate that water so that you can use it.
Take an empty, clear 2 liter soda bottle and fill it with water from the swimming pool. Seal the bottle, and let it stand in direct sunlight for, say, 8 hours. The sunlight will degrade the chlorine enough to make it drinkable. Also, if you have aquariums, you probably have dechlorinator that you add to make the water safe for fish. This should work well to dechlorinate pool water as well.
Also, remember that the only water that needs to be sterilized is water you intend to use for drinking and cooking. Water used to clean clothes or to work the toilet does not need to be sterilized or dechlorinated , for obvious reasons.
Now, for watering plants. I don’t know that it is that big of a deal myself, unless the pool has abnormally high levels of chlorine in it (like your eyes would be burning if you swam under water for a bit). My plants have never suffered, certainly not the grass, when I have discharged overflow from the pool.
That being said, I found something that was interesting without any digging.. This was interesting. Probably an experiment done by a high school person, but useful nonetheless. Long term, that might be another story.
I would much prefer not to add a de-chlorinator (you can buy it for like fish tanks I think it’s sodium trichlorate) on top of everything else before using it to water plants.