Watching "Watergardens" programme on tv recently they made a water feature as shown below.

It was a rill with the water falling to "no-where" The water actually falls into a 4 inch pipe flush with the ground (as shown) the area around the pipe is surrounded by grasses of increasing height.

My only "problem" with this is apart from it looked awful when the wind blows the water will not go down the pipe but onto the soil, this will eventually empty the feature, perhaps that's why the reservoir was    70  x 70 x 70 cm 

A better idea would have been to make a "funnel" at the top of the pipe to give a bigger catchment area. Oh wait a minute, were these not the two guys who drilled a hole trough through some galvanised steel pulled a pump cable through and just put mastic around it? Yes,yes it was. It goes to show you should never take as what you see on TV as being always the right thing to do.

You should never pull a cable through steel, the cable may get chaffed as you do it and as the cable gets moved it will get cut into by the steel, always use a gland