Use of a conceptual hydrogeological model and a time variant water budget analysis to determine controls on salinity in Lake Burrumbeet in southeast Australia

Abstract

Lake Burrumbeet, which is located in the basalt plains of western Victoria, Australia, has a much lower salinity than other lakes in the region. To determine the factors causing the freshness of this water body, an assessment was carried out using existing geological information to reconstruct the palaeotopography beneath basalt flows, and using hydrogeological data, bore hydrographs and hydrological data together with a time variant lake water balance analysis calibrated from 1998 to 2008. The calibrated water balance of Lake Burrumbeet shows that groundwater outflow has a major influence on lake levels (31 % of water losses). The lake water budget analysis confirms that the interaction of Lake Burrumbeet with the surrounding groundwater system is volumetrically significant. Geological re-construction of the course of the buried river valley sediments (Deep Lead underlying the basalt) shows that they run directly beneath Lake Burrumbeet. Groundwater leakage into these sediments is sufficient to transfer enough salt from the lake to maintain a low to moderate lake salinity. The conceptual hydrogeological model of Lake Burrumbeet, coupled with the time variant water budget analysis, show that the difference in salinity among the lakes in the region can be explained by variations in the configuration and hydrogeological setting of the lakes, and this hypothesis provides new understanding of the relative freshness of the lake.

Highlighting the Role of Groundwater in Lake– Aquifer Interaction to Reduce Vulnerability and Enhance Resilience to Climate Change

“…The optimized specific yield compares reasonably with previous specific yield estimates of the basalt aquifer, which range up to 0.18 [51]. The aquifer area in hydraulic contact with the lake (45 km 2 ) is significant compared with the catchment area of Lake Linlithgow (85 km 2 ), indicating that lake level fluctuations directly impact about half of the basalt aquifer in the catchment area.…”

“…When the groundwater component is added to the model, it accurately follows the observed levels ( Figure 11). reliable and modest tool to see the lake-groundwater relationship at a glance and will be useful if constrained by the mass balance and reliable estimate of parameters [9,32,51]. This approach could be adopted for much wetland management.…”

Engineering and environmental remediation scenarios due to leakage from the Gulf War oil spill using 3-D numerical contaminant modellings

“…These may include: recharge, discharge, flow direction, geology, and contamination in the local and regional context. The model is an approximation and presents the understanding of how the hydrogeological system is understood to work (Yihdego and Webb 2015;Yihdego and Paffard 2016;Yihdego and Webb 2016;. Figure 3 presents the conceptual hydrogeological model used to develop the numerical model.…”

Wypływy wód podziemnych w dnach mis jeziornych na przykładzie Jeziora Raduńskiego Górnego (Pojezierze Kaszubskie)

“…2014a ). Z kolei straty poprzez odpływ drogą podziemną mogą wynosić nawet 30% sumy bilansowej, czego przykładem może być jezioro Burrumbeet położone również w Australii ( Yihdego, Webb 2015 ). W przypadku analizowanego jeziora ( Raduńskie Górne ) wielkość zasilania drogą podziemną szacowana jest przez Okulanisa ( 1981 ) na ok. 28%, a straty poprzez odpływ podziemny na ok. 10%.…”