This is this guy's opinion, it may or may not be a valid interpretation. SpaceX is by far the world's largest operator of space launch deluge systems and other than south texas operates 3 coastal pads, with dozens of launches per year...each.

In this case, a retention pond and collection system does exist. However, when the system is starting and stopping there is overspray outside of the launch area that doesn't get collected. This water is potable and ambient temperature though.