Modelling historical lake levels and recent climate change at three closed lakes, Western Victoria, Australia (c.1840-1990)

Abstract

Lake levels of three hydrologically closed maar lakes, Lakes Keilambete, Gnotuk and Bullenmerri in Western Victoria, Australia, have declined since the first recorded observations in 1841. High levels were previously sustained for several centuries with the lakes in climatic equilibrium. Historical survey and field investigations provide a detailed picture of both historical land-use changes and of the geological and hydrogeological influences on the water budget. Groundwater components include baseflow from deep percolation within the catchment and discharge from a surrounding low-yield aquifer. A perched watertable at Lake Keilambete helped maintain high lake levels. Climate records back t..