Tasmania Plans $300 Million Irrigation Scheme Drawing Water from Derwent River

Tasmania's state government is advancing a $300 million irrigation project that will draw 37.2 gigalitres of water per year from Lake Meadowbank on the River Derwent beginning in 2030. The Greater South East Irrigation Scheme targets one of the state's driest farming districts and forms part of a broader plan to raise the annual value of Tasmanian agriculture to $10 billion by 2050.

The project has secured $150 million in federal funding, $75 million from the state government, and $75 million from irrigators. Water will be taken upstream of the Lake Meadowbank dam wall, with releases intended to maintain downstream river flow. A state environment department spokesperson said the scheme will protect freshwater quality and river health while meeting existing commercial water supply agreements.

Irrigation withdrawals would pause if flows fall below set thresholds.

2002 Study A 2002 study commissioned by the state environment department advised against further water abstraction from the lower Derwent between January and April to avoid risks to river and estuarine environments. A co-chair of the Tasmanian Independent Science Council said the government has not commissioned a new independent study on summer extraction impacts since that report.

The same scientist noted that the 2002 findings have not been disproved and called for updated research before the scheme proceeds.

Tasmania stated the scheme represents 1.6 percent of average water discharged from Meadowbank between October and March and will not change system operations or existing flow commitments. Tasmanian Irrigation said environmental studies will be conducted in consultation with state and federal regulators as the project advances.

Water from the scheme has already been sold to demonstrate demand ahead of construction.