The Lake Cargelligo weir and regular are 7 miles from to town, and the total capital expenditure of construction up to the beginning of 1913 when the water Conservation and irrigation commission assumed control was $71, 684 including lakes and canals. The weir is of construction, placed in a bend of the Lachlan River. The crest length is 261 feet (79.5 metres), height above river bed 18feet (5.5metres) and capacity about 680 area feet. Water is held back about 15 miles (24kms). A short distance above the weir a cutting has been constructed from the river which diverts water via ‘sheet of Water Lake” and “Curlew Lake” into “Lake Cargelligo”. A regulator at the head of the cutting controls the flow into the lakes. Water is released from Lake Cargelligo via Lake Creek, which is also provided with a regulator, Lake Cargelligo storage has no true catchment and relies on river flows, surplus to normal requirements, to provide stored water. The main function of the storage is to supplement downstream river flows during dry spells. The storage is located in a natural depression area and the water is confined in sections by earth retaining banks. Originally Lake Cargelligo drew its supplies from the Lachlan River through Lake Creek when the river rose 12 feet (3.6 metres) above summer levels, and emptied through the same channel as the river fell.