These clients wanted a pondless waterfall beside their new (under construction) swimming pool. So we built this big 10,000 GPH feature, and created a space behind it for all the pool equipment to be hidden out of site. The video for this feature will be uploaded to YouTube for you to get the full effect of the sound and shear volume of this feature.
Footings for the wall to support the weight of the waterfall and hide pool equipment/electrical etc.
The block wall is to support the waterfall, and hide the pool equipment. Here we are adding the dirt for the falls
Rock slabs are in, here is the pit/reservoir to hold the water for the feature. To be extra cautious, we used several layers of underlay, then 45mil EPDM liner, then extra liner for protection, and more underlay over the liner. There's no way to puncture this waterfall, unless you really tried hard. As you can see, we use 4" perforated pipe, cut to fit, overlapping in several directions (like layers of lasagna)
When I find the finished pictures, I'll post them here. Until then, hopefully this gives you some ideas