Mapped high watertables and salinity affected areas in the small Rosedale Salinity Province is nearly all found on the south floodplain of the LaTrobe River at about the same elevation of 18 metres.
The main Groundwater Flow System (GFS) is regional scale and associated with the ‘Haunted Hills Gravels’ that extend south to the Strezlecki hills. The local to intermediate scale GFS of the LaTrobe River floodplain sediments overlie this along the Princes Highway corridor through Rosedale. These low-lying areas were naturally wet and probably had a high watertable, so it was inevitable that draining these areas in an attempt to convert them to dryland grazing land has resulted in salinity problems. Following periods of higher rainfall (and hence increased recharge), salinity has emerged as groundwater levels rose and discharge zones in and around Rosedale Township became active. At least 500 hectares of high watertables coupled with brackish groundwater have been mapped, but other areas at similar elevation and landscape location are probably also at risk.
Management options should focus on higher plant water utilisation in higher elevation areas and the removal of low-lying areas from production for restoration as wetlands.