The Leslie Dam is a concrete gravity dam across Sandy Creek, a tributary of the Condamine River, located in the epyonomous settlement of Leslie Dam, near , in the Southern Downs region of Queensland, Australia. Completed in 1965 to form Lake Leslie, the reservoir provides irrigation to approximately of farm land in the region, and supplies potable water to Warwick and surrounding settlements.
Operated by SunWater, the dam was named after Patrick Leslie (1815âÂÂ1881), an early settler in the region and the first person to buy land in Warwick.
The dam wall is high and in the range of long. The resultant reservoir has a capacity of when full, and covers , drawing from a catchment area of .
The initial construction was completed in October 1965 and created a reservoir with of water storage capacity. In 1986, the dam wall was raised by and seven controlled hydraulic-operated radial gates were added to the spillway, each wide and high. The improvements resulted in more-than doubling the capacity of the reservoir to .
The dam's highest level was reached on 12 September 1988 when waters in the dam peaked at above the spillway. The next highest level was above the spillway on 28 May 1990. On 11 February 1995, the dam reached its lowest level ever of 3% capacity.
The Leslie Dam as part of spillway capacity upgrade program commenced in 2008 by SunWater to ensure a consistently high level of safety for the dams under their control.
On 5 January 2011, the dam spilled for the first time in more than two decades and all seven floodgates were opened. Downstream of the dam, the Sandy Creek was flooded and the Cunningham Highway was forced to close. Warwick's mayor, Ron Bellingham, called on SunWater to reduce the flow of water from the dam, that was put into effect the following day.
On 21 October 2001, sculpltures of Patrick Leslie and his wife, Kate, were unveiled as part of the Centenary of Federation Celebrations and as a tribute to pioneering women. The sculptures are located near the dam wall.
Freshwater fishing and water sports facilities are available on the reservoir. A Stocked Impoundment Permit is required to fish in the dam.
An upgrade of recreation facilities at Leslie Dam was announced in 2022 and completed in 2024.