Commenced in 1917 and completed in 1926, the Chichester Dam is a minor dam on the Chichester River, a tributary of the Williams River. The dam contributes about thirty-five percent of the lower Hunter region's water supply.
The dam wall is 43m high and is 254m long and was constructed using a cyclopean system of interlocking concrete blocks and large boulders with a volume of 91 m3. The wall is anchored to the bedrock below it by 93 stressed tendons. At 100% capacity, the dam wall holds back 21,500 ML of water at 156.2 mAHD. The spillway is capable of discharging 3,300 m3/s. The surface area of the reservoir is 1.8 km2 and the catchment area, largely located within the Barrington Tops National Park, is 197 km2. The dam is connected to reservoirs in Maitland, Cessnock and Newcastle by an 80 km long gravitation main pipe.