MIP first-stage sites finalised

June 14, 2018

First stage catchment repair sites have now been finalised for the Major Integrated Project (MIP) - a reef water quality initiative that is the first of its kind in the Wet Tropics.

More detailed investigations are taking place at these catchment repair locations to inform engineering design work. And expressions of interest are now being sought for construction-related services.

More than 40 on-farm sites in the Johnstone and Tully River catchments have been assessed as possible catchment repair locations.

Catchment Repair Project Officer Suzette Argent said the team had covered a lot of ground.

“We are hoping to have two wetland sites constructed by end of 2018, to get as much monitoring time as possible,’’ she said.

Catchment repair and treatment systems have the potential to reduce nutrient and sediment loads entering the Great Barrier Reef, and their effectiveness in the Wet Tropics will be trialled and monitored over the life of the project.

The Wet Tropics MIP is funded by the Queensland Government and designed by the local community.

A consortium of more than 40 organisations, and hundreds of community members pooled their knowledge of the Tully and Johnstone catchments to design a program tailor-made to the environment.

‘Walking the Landscape’ workshops – where scientific information from maps and reports is combined with decades of local knowledge – has helped with the selection of possible catchment repair sites.

Suzette is working closely with Mark Bayley from Australian Wetlands Consulting, who has more than 15 years’ expertise in catchment repair. The pair worked together on Australia’s first bioreactor, on a Sunshine Coast pineapple farm.

“There are different criteria we need to consider. Most importantly, landholders have to be open to the idea of us working on their land,’’ Suzette said. “We are really encouraged by the level of willingness so far. Growers are keen to drive water quality improvements.

“We also need to know if the right technology is going in the right spot. During a preliminary site assessment, we’ll check to see if the site is in a low point in the landscape and if it has the ability to intercept the base flow, or the constant and steady flow of water, as well as storm flows.

“The MIP is all about local knowledge informing action. The success of catchment repair technologies are reliant on knowing how the water moves, and who better to know this than landholders who live here.”

Suzette and Mark also take the wetland-to-catchment size ratio into account when making their recommendations.

Wetland size, treatment area size and the amount of land that would need to be taken out of use (if any) help to give a theoretical dissolved inorganic nitrogen (DIN) reduction rate in kilograms per year, which is compared to the cost of construction. In short, this gives a cost per kilo of DIN removed, and provides a good value-for-money check.