No one is going to ever think that this waterfall exists naturally, but at least I am hoping that turns out to be believable or at least nice looking.
It’s very easy to build an unbelievable waterfall – most of the constructed waterfalls I’ve seen are terrible, Even some “professionally built” waterfalls tend to leave me wondering if the builders have ever seen a natural waterfall (and how much the client paid for that monstrosity). Consider this pile of rocks in the image to the left - it's a great example of everything NOT to do.
There are, fortunately, great waterscape builders out there to mimic, and a few are very enthusiastic to share their knowledge. One of the best examples is The Pond Digger in Southern California who has a number of YouTube videos taking about the details of pond and waterfall construction. I have watched each of his videos several times – a great resource.
Even though I have meditated on building my waterfall for over half a year – and I could continue for another two years just thinking about it – I am going to move forward with the acknowledgement that I have to be very conscious of believability.