Waterfall Spillways & Outlets
Create a controlled waterfall return from a pond or hidden reservoir
Spillways spread pumped water across a defined outlet so it can form a sheet, cascade or broad stream entry. This category includes the Oase Spillway Box range, Oase Water Reservoir Wall 60 and Pontec PondoFall waterfall outlets.
Choose from the desired outlet width and effect, then calculate the pump flow at the actual lift. The spillway must be installed perfectly level: even a small error causes most of the water to favour one side.
Flow per width determines the appearance
A wider outlet needs more delivered flow to maintain the same thickness of water. A gentle film, broken natural cascade and projecting sheet all need different flow and lip geometry. Use the manufacturer’s recommended range and remember that pump output falls with height and pipe resistance.
Level, liner sealing and access
Build a stable base that will not settle, level the outlet across its full width and test with water before permanent stonework is completed. Follow the specified liner flange or connection method; trapped folds and overtightened fasteners can create leaks.
Leave access to the inlet and internal chamber so leaves, stones and biofilm can be removed. Use a valve where adjustment is needed, but do not rely on a severely throttled oversized pump as the design method.
Pair the outlet with water-feature reservoirs and pump vaults, or browse stainless water blades for a more architectural projecting sheet.
Frequently asked questions
How much pump flow does a spillway need?
That depends on weir width, desired effect and total head. Use the outlet’s recommended delivered-flow range.
Why does water run only from one side?
The spillway may be out of level, the inlet flow uneven or the chamber partially blocked.
Can a spillway sit above pond level?
Yes, provided the pump can deliver the required flow at that lift and the return is safely contained.
Do I need a liner flange?
Use the manufacturer’s specified sealing method for the exact outlet and liner construction.
Can I hide the box completely?
Conceal it visually while retaining service access to the chamber and connection.
Why does a water sheet break up?
Low or turbulent flow, an unlevel lip, contamination and wind can all disrupt the sheet.
Is PondoFall an Oase product?
PondoFall is a Pontec range. It belongs in this functional waterfall category rather than the Oase-only archive.
Can I use narrow hose?
It may severely reduce delivered flow. Use the recommended bore and minimise restrictive fittings.
