William Napper and his first wife, Ann (Buckland), emigrated to South Australia in 1855 and settled at Lake Bonney. He operated the Lake Bonney Hotel (later known as Napper's Accommodation House) for many years, and was proprietor of the Overland Corner Corner Hotel for a few years.
William is thought to have been the first person to irrigate from the Murray River in South Australia. In about 1889, he used a steam engine and pump on the creek to water his vines and fruit trees which were growing on dry sandy soil. About two acres of land was irrigated.
Ann Napper died in about 1860, reputedly the first white woman to die in the district. A memorial cairn was erected in her memory. It is located near a picturesque lagoon on the road between Cobdogla and Kingston.