PERFORMANCE tests are underway to add fluoride to water at the Image Flat treatment plant in Nambour.

Fluoride also will become a standard ingredient in water supplied from Ewen Maddock and Lake Macdonald dams in the near future.

After major treatment plants such as Landers Shute introduced fluoride in 2008 in stage one, smaller plants were scheduled to be on line by December 31 last year.

Landers Shute treats water from the Coast’s 61,000 mega litre Baroon Pocket Dam, which supplies the southern end of the Coast.

At Image Flat, a fluoride facility has been built, but chemical commissioning performance tests are still being carried out.

Proof of performance testing by contractors takes 14 days, during which defects can be identified before the system is handed to SEQWater.

The tests involve fluoride dosage into the water supply.

A SEQWater spokesman said the fluoridisation of 20 smaller treatment plants mainly serving the Coast’s regions north of Maroochy River was underway in stage two of the process.

Ewen Maddock Dam, located at Landsborough, acts as a supplementary supply to the Caloundra area.

The spokesman said fluoride levels could fluctuate initially as a build-up from 0.4 milligrams per litre was raised during six to 12 months to an optimum health-providing concentration of 0.7 to 0.9 milligrams per litre.