Environmental flow assessment of the Lower Coal River and Pitt Water Estuary

Abstract

This report describes a project designed to derive an environmental flow regime for the lower Coal River, southern Tasmania, downstream of Craigbourne Dam, and its estuary and related coastal embayment, Pitt Water. Within the current Tasmanian water management policy context, the principle aim of an environmental flow regime is to maintain existing values. This implies a focus on existing conditions. However, opportunities for environmental rehabilitation/ restoration should also be explored where they are broadly commensurate with the existing water management focus, which in the lower Coal is on irrigation water supply. The Coal catchment has been extensively cleared for grazing, and development for intensive agriculture has been stimulated by the development of irrigation infrastructure. This development has had a number of consequences for the Coal River and Pitt Water, whose environmental condition is discussed in Sections 2-4 of this report.