The results are in for a beach boosting trial carried out off Maroochydore late last year.
It took place on a small scale in a tricky location to see if it could be used to replenish beaches on the Sunshine Coast in the future.
The Nearshore Nourishment trial used a trailing suction hopper dredge to carry sand from the Spitfire Channel, in Moreton Bay, to Maroochydore Beach.
Two techniques placed sand just offshore by either “rainbowing’’ or bottom placement.
During rainbowing, sand was mixed with water and sprayed from the ship’s bow in a huge arc, like a rainbow. With bottom placement, sand was released from the bottom of the hull in a grid like pattern.
This happened about 300m offshore with waves, currents and tides then carrying the sand toward the shoreline helping buffer it against future storms and coastal erosion.
Following a review of the data, Sunshine Coast Council has concluded that it did produce an increase in sand on the beach.
It found the technique could potentially be used on a larger scale for future nourishment campaigns along Maroochydore Beach and in other coastal locations.
Sunshine Coast Council’s Environment Portfolio Councillor Peter Cox said Council had used data from experts, surveys and reports to determine the outcome of the trial.
“The trial showed us that yes, the science is correct and the technique is viable for placing larger quantities of sand in the future if needed,” Cr Cox said.
“While there are things we can improve on, we now know that nearshore nourishment is a quick way to place a lot of sand on the beach and with these results, Council can now consider it as beach replenishment option in the future if needed.”
Visit haveyoursay.sunshinecoast.qld.gov.au and search nearshore nourishment for a full summary of the outcome of the trials.
