The Buckingham Canal is a salt-water navigation canal with a length of 420 km. It extends parallel to the Coromandel Coast of South India from the Krishna District in the state of Andhra Pradesh to the Villupuram District in the state of Tamil Nadu. The canal joins majority of the natural backwaters along the coast to the port of Chennai (formerly Madras). It was built by the British Raj, and was a significant waterway throughout the late nineteenth and the twentieth century.

The first section of the canal was built in the year 1806, from Chennai north to Ennore. After that, it was stretched towards the Pulicat Lake, 40 km north of Chennai.The canal came under the jurisdiction of the Madras Presidency in 1837 and was again extended. It eventually extended up to 315 km north of Chennai to Peddaganjam on the Krishna River in the Krishna District of the state of Andhra Pradesh, and 103 km south of Chennai to Marakkanam in the state of Tamil Nadu.

During the years 1877 and 1878 the people of Chennai fell prey to a terrible famine. More than 3 million people died. The eight-kilometre stretch, connecting the Adyar and the Cooum rivers, was constructed in 1877-78 at a cost of Rs.3 millions to aid the famine-affected people. The canal received the name Buckingham Canal in 1878 because the link was built under the supervision of the then Governor, the Duke of Buckingham and Chandos. The canal runs around 1 km back from the shore. The Cooum River joins the canal to the Bay of Bengal in the heart of Chennai. The segment north of the Cooum is called the North Buckingham Canal, and the section south of the Cooum is known as the South Buckingham Canal. 257 km of the total length of the canal is in Andhra Pradesh, and 163 km is in Tamil Nadu. About 31 km is within the city boundaries of Chennai.

The Buckingham Canal was previously used to transmit goods up and down the coast to Chennai. The cyclones of 1965, 1966 and 1976 spoiled the canal, and it is currently of little or no use. Inside the city of Chennai the canal is shoddily contaminated from sewage and industrial effluent, and the silting up of the canal has left the water sluggish. But the nice thing is that during the 2004 Indian Ocean tsunami, the Buckingham Canal acted as a safeguard zone and regulated the tsunami waves on the coastal area over almost 310 km from Pedda Ganjam to Chennai.

The canal all along the coastline was packed with tsunami water, which poured out at a few places and retreated back to the sea within 10 to 15 min. This helped a long way in saving the lives of a number of fishermen, particularly in coastal Andhra Pradesh and fractions of the Chennai city and also helped in clearing the aquaculture remains. The natural growth of vegetation on both the sides of the canal also helped in listening the impact of the tsunami.