Death of a Lake by Arthur William Upfield
"On a vast sheep station in the outback, Raymond Gillen goes swimming in the lake one night and is never seen again. After the failure of local police to solve the mystery, Bony arrives disguised as a horse-breaker, and uncovers a story of sexual tension and murder. The lake is evaporating in the intense drought - only when it dies will the mystery be solved. Apart from its strengths as a crime novel, this is probably the best book ever written about drought in Australia."--Back cover.