Hydrology of the upper Hunter catchment

Abstract

One of the ten objectives of the 2004 Australian National Water Initiative is to manage surface and groundwater as a single resource. In order to do that it is necessary to understand the interactions between surface and groundwater, as well as the impacts of water abstraction, land use change and climate variability. In Australia, not just the quantity of water, but also its quality and particularly its salinity are critically important. Some of the difficulties facing agencies in managing surface and groundwater as a single resource are the extreme variability of climate in Australia, the lack of long-term streamflow and groundwater level data sets and the very limited temporal records on water quality. This thesis presents a study of surface and groundwater interaction and salinity in a selected catchment in the Hunter Valley in mid New South Wales, eastern Australia, where data records are limited and incomplete. The hypotheses tested in this work are that (1) salinity discharge in the Hunter is largely determined by mineral weathering and deep groundwater inflows and (2) a simple parameter-efficient coupled surface and groundwater model can accurately predict groundwater and streamflow behaviour over monthly time scale and is useful in determining surface-groundwater interactions.<....>