The Buckingham Canal, a navigation canal along the east coast, runs through Tamil Nadu and:

The Buckingham Canal is a long, salt-water navigation canal that runs parallel to the east coast, from near Kakinada in Andhra Pradesh to Villupuram district in Tamil Nadu, passing through Chennai. Its total length is about 796 km.

History:

• It was first built as a private canal, the Lord Clive Canal, in 1806, near Chennai.
• It was extended in stages during the 19th century.
• During the Great Famine of 1876-78 in the Madras Presidency, it was widened and extended as a famine relief work, giving employment to thousands of people.
• It was named after the Duke of Buckingham, the Governor of Madras at that time (1875-1880).

Purpose and uses:

• It was built to provide a safe inland waterway for transporting goods, such as salt, firewood, food grains and other goods, along the coast, avoiding the rough sea.
• It connected the natural backwaters and lagoons of the coast, including Pulicat Lake.
• It played an important role in trade along the east coast until the early 20th century, when railways and roads took over.

Decline:

• Silting, encroachments, pollution and storm damage reduced its use.
• The 2004 tsunami damaged parts of the canal, though it also reduced the impact of the waves in some places by absorbing their force.
• In Chennai, parts of the canal are heavily polluted with sewage.

National Waterway:

The Buckingham Canal, along with parts of the Godavari and Krishna rivers and canals, forms part of National Waterway 4, declared in 2008 and extended in 2016.

Other coastal canals of India:

• The West Coast Canal in Kerala (National Waterway 3).
• The East Coast Canal in Odisha and West Bengal (National Waterway 5), along with parts of the Brahmani and Mahanadi.

Why not the other options?

• ✗The Buckingham Canal does not pass through Odisha, Kerala or Karnataka.