Towards a water resource policy for African mahogany plantations in the Douglas Daly Basin

Charles Darwin University

We were engaged to contribute to the development of a water resource policy for African mahogany plantations in the Douglas Daly region in the Northern Territory.

The purpose of the water resource policy was to embed the results of ongoing research relating to water use in large-scale African mahogany (Khaya senegalensis) plantations in the water planning framework.

The mid-2000s saw an unprecedented surge in demand for land in the Douglas Daly region, which resulted in the establishment of a forestry estate covering 10,000 to 12,000 ha (in 2011) and which may expand to 30,000 ha. These plantations were non-irrigated and established on regrowth or previously cleared freehold land so did not require formal assessment under the Planning or Environmental Assessment Acts or licensing under the Water Act.

The Douglas Daly Basin encompasses highly valued and significant economic and environmental assets including rivers and streams whose dry season baseflows are sustained by groundwater. Research undertaken by Charles Darwin University and the CSIRO suggests there is currently a low risk of impact on the water resources of the Douglas Daly Basin as the water balance of native vegetation and non-irrigated African mahogany plantations were similar.

It was therefore recommended that this land use does not require a water allocation licence under the Water Act. Further work is required, however, to reduce the significant uncertainties associated with outcomes of this research and to inform the policy review process.