Kallang Basin is an enclosed bay in Kallang, Singapore. The Kallang River, Rochor River and Geylang River empty into the Kallang Basin. The Marina Channel connects the Kallang Basin with the Singapore Straits. At present, the Kallang Basin forms part of the Marina Reservoir, so do the rivers that flow into the Kallang Basin and their tributaries. The reservoir has a catchment size of nearly one-sixth of mainland Singapore's land area. The Kallang Basin is a popular location for water sports, in particular, kayaking and dragon boating. Today, the area surrounding the body of water is also frequently called "Kallang Basin". The term has been applied to the industrial estates along Kallang Bahru, the Kallang Basin Swimming Complex, amongst others.
Much of the lands around Kallang Basin are the result of extensive land reclamation. Areas of the modern-day Singapore Sports Hub, the former Kallang Airport, the condominium clusters along Tanjong Rhu Road, the industrial estate at Kallang Bahru, and the area south of Nicoll Highway were once part of a much larger Kallang Basin prior to land reclamation. Numerous islands also existed in the Kallang Basin, including Pulau Mengalu which was located at where modern-day Bendemeer MRT station is. At its greatest extent, the Kallang Basin once extended as far north as today's Bendemeer Road. From the late 1960s to early 1970s, the part of Kallang Basin to the north of Kallang Road underwent land reclamation. The Kallang River and its tributaries were also canalised to prevent flooding. The Kallang Basin area once formed part of mainland Singapore's southeastern coastline. Its access to the Singapore Straits was only cut off when the Marina Barrage was completed over the Marina Channel in 2008.
While the Raffles' Landing Site on the northern bank of the Singapore River is generally thought to be the original landing spot of Sir Stamford Raffles in 1819, other sources point to the Kallang Basin area as the likely location. According to the Cho Clan Archives, Raffles ordered his ship's carpenter, Chow Ah Chi, to lead the way in posting the British East India Company flag on mainland Singapore and he supposedly landed at the mouth of the Rochor River in Kallang. Raffles, following the route taken by Chow, also arrived at the Kallang Basin in what is today's Kallang Riverside Park. This was possible because the Kallang Basin was directly connected to the open sea at the time of Raffles' founding of modern Singapore.
