South Arm irrigation pipeline set to roll

FARMERS in the South Arm peninsula region will soon have access to irrigation water thanks to a new innovative pipeline. 

The $1.1 million, 7km pipeline will cross the Derwent River between Blackman’s Bay and Algona Street at South Arm. 

The pipeline, which will be floated and then sunk over a three-week construction period, will deliver Class A recycled water to the region for farmers, firefighting and other community uses. 

A decade in the making, the pipeline will be laid by being floated in 500-metre segments into position from the Margate staging area, bolted and then sunk. 

South Arm Irrigation Scheme chief executive officer Mary Massina said that the float and sink of the pipeline was an historic occasion for the South Arm community. 

“South Arm is one of the driest areas in Tasmania with limited agricultural capacity, as it is in a rain shadow from kunanyi/ Mount Wellington, and without access to natural fresh-water sources,” Ms Massina said. 

“The South Arm Irrigation Scheme will be a real gamechanger for the area.” 

Ms Massina said the project will take one-third of the wastewater from the existing TasWater facility at Blackmans Bay, and rather than discharging it directly into the Derwent River, will further treat and deliver up to 900 mega-litres of Class A water per year to the Peninsula through the new pipeline.” 

South Arm Irrigation Scheme COO Michael Kerschbaum said that in 2021 the company commissioned Pinion Advisory to undertake a review of the potential for irrigated agricultural land use on the South Arm Peninsula. 

“Currently, around 40ha of the Peninsula is under agriculture,” he said. 

“The South Arm Irrigation Scheme has the potentional to increase this by a massive nine times, to 350ha. Based on the climate and soils, the most suitable options for new irrigated agricultural crops include high value crops such as cherries, viticulture and olives.” 

Mr Kerschbaum said the company has already signed MOUs for the purchase of irrigation water with all major landholders on the water pipeline route. 

All up, in conjunction with the construction of the water treatment plant in Kingston and on-land irrigation pipe at South Arm, the scheme and the Arm End Golf Course projects are expected to create 150 direct and indirect jobs during construction, and at least 100 jobs after construction through increased economic development due to water certainty. 

It is anticipated that the first treated Class A recycled water from the Blackmans Bay water treatment facility will cross the river in early 2025.