Bikenibeu is a settlement in Kiribati. It is located close to the southeastern corner of the Tarawa atoll, part of the island country of Kiribati. It is part of a nearly continuous chain of settlements along the islands of South Tarawa, which are now linked by causeways. The low-lying atoll is vulnerable to sea level rise. Rapid population growth has caused some environmental problems. Kiribati's main government high school, King George V school, is located in Bikenibeu, as well as the Ministries of Environment and Education.
Bikenibeu is one of the three main urban centers in South Tarawa, the others being Betio and Bairiki. Starting in 1963, causeways began to be built between the islands of the atoll to make communications easier. The causeways connected Bairiki to Bikenibeu by 1963, and extended from Bikenibeu to Bonriki by 1964, when flights began from the new airport to Fiji.
Bikenibeu island lies between the Tarawa Lagoon to the north, with a maximum depth of 25 metres (82 ft), and the Pacific ocean to the south, with a depth of up to 4,000 metres (13,000 ft). The island has been built from sediments from the lagoon. The process of soil accumulation is driven by the dominant easterly trade winds, and can be reversed during extended periods of westerly winds during El Niño-Southern Oscillations. Bikenibeu is an average of 3.25 metres (10.7 ft) above sea level on the ocean side, and 2.38 metres (7 ft 10 in) at the lagoon side. Tidal flats on the ocean side extend for 160 metres (520 ft). ACLR (Accelerated Sea-Level Rise) is a serious concern. In a scenario where a sea level rise of .5 metres (1 ft 8 in) occurs, 71% of Bikenibeu would be flooded by a spring high tide. With a rise of .95 metres (3 ft 1 in) the tide would flood the entire island.