A detailed streamflow and groundwater salinity dataset for Muttama Creek Catchment, NSW, Australia

Abstract. Dryland salinity remains a major global natural resource management concern, and which is amplified in Australia. However, limited detailed space-time data sets with observations of stream and groundwater salinity has constrained a deep understanding of the range of processes that can lead to dryland salinity problems in landscapes. The aim of this study is to report on the open dataset (https://doi.org/10.25910/m0wp-8890, Vervoort et al., 2025) resulting from a 14 year data collection effort in a subcatchment of the Murrumbidgee catchment in New South Wales, Australia. Over a 14 year period a series of different sampling campaigns has resulted in a large dataset with hydrogeochemical data which includes both in-situ (field) data and post laboratory analysis of major anions and cations. This data is augmented with observed groundwater levels and publicly available streamflow and climate data (https://doi.org/10.17605/OSF.IO/BEUWK, Vervoort and Akter, 2024). The data set covers 23 groundwater sample sites and 39 surface water sites. Because the data was collected by four distinct groups and over many years, we investigate whether this has caused a bias in the dataset. In addition, we show the major spatial and temporal trends to provide an overview of the dataset. The dataset is made open access to encourage further research and the current paper shows the richness of the collected data and opportunities for further research.