Onehunga is a suburb of Auckland in New Zealand and the location of the Port of Onehunga, the city's small port on the Manukau Harbour. It is south of the city centre, close to the volcanic cone of Maungakiekie / One Tree Hill. Onehunga is a residential and light-industrial suburb. There are almost 1,000 commercial and industrial businesses in the area. Onehunga stretches south from Royal Oak to the northern shore of the Manukau Harbour. To the east are the areas of Oranga and Te Papapa; to the west, Hillsborough. On the southern shore of the Manukau Harbour, and linked to Onehunga by two bridges, is the suburb of Māngere Bridge. Geography Onehunga lies on the Auckland isthmus, on the northern shore of Mangere Inlet, an arm of the Manukau Harbour, and just south of the volcanic cone of Maungakiekie / One Tree Hill. The Port of Onehunga, on Manukau Harbour, is now much smaller than Auckland's east coast port on the Waitematā Harbour, but in the 19th century it was the larger. The wharves are located on reclaimed land bordering a low volcanic crater called Te Hopua, once occupied by a tidal lagoon opening to the southwest, but which has also been reclaimed. Onehunga's southwestern side, near the Manukau Harbour, lost its direct waterfront access when the Southwest Motorway was built there in the 1970s. Only a tidal lagoon remains on the city side, though in 2008, there were proposals that the motorway (which was to be widened) could be sunk into a trench to provide direct access to the harbour again. In 2013, a project was underway to restore the Onehunga foreshore, to be connected to the city-side park by a pedestrian and cycle bridge over State Highway 20. A substantial aquifer flows underground beneath Onehunga, feed by rainwater soaking through the lava flows around Maungakiekie / One Tree Hill. Up to 21 million litres of potable water a day is pumped from the Onehunga aquifer and treated in a local plant before being supplied to Onehunga as part of the Auckland water supply network. While most of Auckland's potable water comes from reservoirs in the Hunua and Waitākere Ranges, or from the Waikato River, the Onehunga aquifer provides around 5%. In contrast, while the isthmus's other major aquifer, the Western Springs aquifer, is also feed by water seeping through lava fields, it is no longer used as