system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why is collecting rainwater illegal in some states?

Claiming that rainwater harvesting is "illegal.
gpt
Water can be hard to some by in some places. Collecting rain water means that you are interfering with the replenishment of the natural water supply, or artificially worsening the water shortage for neighbors that would normally receive run-off from your property. Essentially, you are keeping water from it's natural course and in a drought condition, that can be devastating for others.