Is there the same amount of potable water as there was 500 years ago?

If you don’t include permafrost or glacier ice there is probably slightly more potable water today due to storage and filtration.

This would be difficult to answer as today’s criteria for potable water is stricter than would have been used 500 years ago. As such many water sources used 500 years would be considered unsuitable for human consumption.

So if you used today’s criteria I would think we have between 10 to 30 times the amount of potable water today.