Weirs along Ross River are still the biggest fishing secret in Queensland.

NQ Water says calls to encourage tourism by promoting local fishing opportunities in Townsville and Thuringowa should be directed to the Aplin, Gleeson and Black Weir storages.

NQ Water Chief Executive Officer Ken Diehm says a 2001 survey by the Queensland Fisheries Service (QFS) unveiled a fishing goldmine.

"The results of the 2001 survey indicate that the three weirs have some of the greatest density of Barramundi of any impoundment in Queensland," Mr Diehm says.

"They are well serviced with amenities like toilets, BBQ facilities and have landscaped and shaded areas. There are also boats ramps and disabled access which make the weirs an ideal point to focus fishing tourism."

The QFS report was part of a wider Recreational Fishing Investigation carried out by consulting engineers Sinclair Knight Merz.

The report also found the weirs a far better option for economic reasons, says Mr Diehm.

"The dam cannot sustain barramundi because they breed in salt water," he says.

"Stocking the dam to a suitable level for fishing would cost around $50,000 a year.

"There are other significant costs, including infrastructure like boat ramps, parking, toilets and safety and security, as well as water quality monitoring and staffing, among others.

"We estimate those costs at half a million dollars in the first year and $200,000 each year following."

The dam is being promoted as a community facility by developing its eco-tourism potential says Mr Diehm.

"Three local companies have been appointed to provide a range of activities including wildlife appreciation, canoe tours and 4WD driving experiences," he says. "These activities are managed and supervised, which means NQ Water can concentrate on providing a healthy, consistent water supply."