This fall, I will be building (DIY) a fountain into our dry-laid backyard rear retaining wall (very ugly yellowish large bricks). I am doing research before hiring the electricians who will need to run the current out to the fountain, and thought I would ask your opinions on a retaining wall fountain. The retaining wall is five feet tall. The soil behind it is builder-fill, extra heavy clay. There is a wooden fence separating our yard from the neighbors on TOP of the retaining wall, set about a foot back. This makes working behind the wall a little more difficult. The fountain would be very simple, a large copper pipe jutting out of the retaining wall about 6-10 inches, with water falling into a bluestone basin I will have constructed (maybe 50-75 gallons)(to match the bluestone patio back there now). One of the main purposes of the fountain will be to generate lots of water noise to drown out nearby traffic, so the goal is to pump a high volume of water into a large water-filled reservoir.

Building this fountain will probably require taking apart the dried laid wall and excavating the earth out, installing the pump line and then rebuilding the wall around the water supply to the copper output pipe(pump will be in bluestone basin, running pump line up to copper pipe. ) Obviously, I have alot more research to do, as I haven't figured out how to get the pump electricity wire out of the basin in a watertight and unobtrusive fashion, or to have the pump tubing mate with the large (2" diameter) copper pipe. I know how to solder, so I was thinking of soldering a connection made out of copper pipe from the back of the 2"output pipe down the rear of the retaining wall and into the bottom side of the bluestone basin to meet the pump tubing there. What I am concerned about is having to backfill the dirt in over either copper piping or tubing (methinks copper is the way to go) and then having to maintain it. How do you maintain a retaining wall fountain? Does the pipeworks behind the retaining wall need to be always accessible? Is there anything I am not thinking about? Thanks in advance for your thoughts.