The Treatment Process

Intake
Using the best available technology to limit the impact on the river and its wildlife, the intake will draw water from the river and a pipeline will transport it to the treatment plant inland.

Storage
Low tide raw water, which has a lower salt content and requires less energy to purify than high tide raw water, is stored until it is needed in the system.

Coagulation
Chemicals are added to small particles in the water, so they can form into larger particles and be removed more easily.

Clarification
Large particles, some organic and inorganic compounds, and PCB’s and radionuclides (if present), are removed from the water by settling at the bottom of a large basin.

Filtration
Small particles not removed through clarification are filtered.

Reverse Osmosis (Desalination)
Filtered water is pumped through a membrane that lets water pass through but blocks dissolved substances such as salt, organic compounds, and, if present, radionuclides and viruses.

Blending
Reverse osmosis produces water of such a high quality that it is stripped of most of its essential minerals. Blending allows water that is not passed through the RO membranes to mix with water that is passed through. The result is a blend that has a mineral content and taste resembling water to which we are accustomed.

Post-Treatment
Reverse osmosis creates virtually pure (and relatively tasteless) water by removing almost all the dissolved salts and minerals, so chemicals such as lime and carbon dioxide are added to reduce the water’s corrosiveness and improve its taste.

Activated Carbon
Granular activated carbon removes any remaining organic chemicals and PCB’s, if present.

DisinfectionIn the final treatment step, the water is disinfected using a very small amount of chlorine to kill any remaining bacteria or viruses.

Distribution
Following disinfection, purified water that meets or exceeds all drinking water standards is pumped to our customers for use in their homes and businesses.