Rainwater collection laws in the US are based on conservation and fair allocation of a scarce resource.

In places that don’t have scarcity, you actually have the opposite issue, where drainage might be restricted or mandated to prevent issues from harming your neighbors.

I can’t build a dam on my property because it might flood my neighbor. People in the southwest can’t collect water at will because it might dry out their neighbors.

This isn’t as bad as it sounds. Water prevented from reaching the ground in watersheds means groundwater doesn’t get replenished. Now maybe a house here and there collecting rainwater isn’t a problem, but what about Nestle? The law should allow reasonable rainwater collection by individuals or family households while preventing theft of water from a region.