Cardinia Reservoir is an Australian man-made water supply dammed reservoir. The 287,000-megalitre (6.3×10¹⁰ imp gal; 7.6×10¹⁰ US gal) water store is located in Emerald-Clematis-Dewhurst in south-eastern suburbs of Melbourne, Victoria. Construction started in May 1970 and was completed in 1973 at a cost of more than A$11.4 million.