Could easily be made with hollow box uprights, run the water tube through one and the top hollow box with a PVC tube that you drill holes in for the water to run out. Faux paint it to look like copper, really pretty easy.
Quick Easy Waterfall Wall - Divider This pergola, showcased at the Notre Dame Home and Garden Show, features a unique water wall designed by Scott. It has a water line that runs all the way along the top beam to drop the water back into the EPDM lined trough. A small pump then runs the water back up the post at the other end.