A curtain of water tumbling down to form a waterfall can have varying widths and heights, As the thickness of the water film depends on these two factors, so will the quantity of water that the pump is required to circulate. Water is pumped by a concealed unit from a lower basin, through one or more pressure lines, into a trough with a shaped overflow, the width and height of which determine the pattern of the waterfall. Most arrangements require an adjustable lip at the beginning of the overflow and a "weir" edge on the other side, With wide waterfalls, the lip should be adjusted perfectly level to prevent the water film from breaking up It is also important that leaves and dirt do not collect on either the "fall-away" or lip,
This can be prevented by a cover, Arrangements frequently combine fountains with waterfalls, with a succession of basins placed on intermediate pedestals one above the other and getting smaller in diameter as they get higher. Water, fed into the top basin, flows in steps down to the lower, larger basins, resulting in a neatly proportioned display of constant water curtains.
- Trough should be adequately dimensioned.
- Lip and weir edge should be kept clean.
- Avoid sitting under trees (leaves and twigs).
- Try to protect from wind.
- Ensure pump is correctly sized.