Assessment of salinity management options for Kyeamba Creek, New South Wales: data analysis and groundwater modelling

A study of the hydrogeological factors influencing salinity in the Kyeamba catchment, NSW, was conducted to describe the physical setting and condition of the catchment and aquifer system, to examine various data interpretations on the conceptual model of flow processes for recharge and discharge, to model the historical and present day hydraulic trend heads and to model possible future salinity mitigation scenarios for the aquifer. The results demonstrate that groundwater levels, and hence salinity concerns are highly dependent on climatic (rainfall) conditions. Targeted perennial plantings would allow direct management of individual saline areas, while longer-term and more extensive reforestation would be required to lower groundwater levels generally. Increased use of pumped aquifers near the confluence of the Murrumbidgee River may negate the need for groundwater flow reduction, though the effects are likely to be restricted to the areas within ten km of the confluence because of bedrock constrictions up valley. The findings could be extended to similar catchments along the west of the Great Dividing Range, but not to higher rainfall regions. Recommendations arising from the study focus on localised management and monitoring.