Reverse Osmosis Introduction

Reverse Osmosis is a process whereby a membrane acts as a molecular filter with an electrically charged surface to remove up to 95 - 99% of dissolved solids and all biological and colloidal matter from water.

Pure water is separated from saline water by a semi permeable membrane which passes water readily but retards the flow of dissolved solids.

Reverse osmosis is used in many places in Western Australia and the world to provide water not normally available by traditional sources.

Generally because of the expensive nature of building these plants they are only used as a last resort. (see explanitory graphic).

Historically because of their large power requirement, they are expensive to operate and consequently the water they produce is more expensive than dams or by extraction from groundwater aquifers.

The Wellington Dam Water Recovery Project will be unique in its operation because very little power is required in the total operations, including delivery.

This is possible because Wellington Dam is 170 metres above sea level, the water falling from this height creates sufficient pressure to force the saline water through the membranes and filters of a reverse osmosis plant located at Brunswick, without needing additional pumping or electricity. The process is similar to the generation of Hydro Electricity. (see explanatory graphic).