Short answers, pulled from the story.
The name River Thames derives from the ancient Brittonic word Tamesas, meaning dark. This etymological root connects the river to the Slavic temno, Lithuanian tamsi, and Sanskrit tamas, all evoking the concept of darkness or muddiness.
The River Thames rises at Thames Head in Gloucestershire and flows for 215 miles to the North Sea. It holds the title of the longest river entirely within England, although the Severn is technically the longest river in the United Kingdom.
The Great Stink occurred in 1858 when the discharge of raw sewage into the river created a toxic open sewer. The crisis was caused by waste from slaughterhouses, tanneries, and gasworks that removed oxygen from the water and raised its temperature unnaturally.
Engineer Joseph Bazalgette supervised the construction of massive sewer systems on the north and south river embankments. This project transformed the river from a death trap into a functioning waterway following the Great Stink of 1858.
The River Thames now supports aquatic life including mute swans, black swans, short-snouted seahorses, tope, and starry smooth-hound sharks. Grey and harbour seals number up to 700 in the Thames Estuary, and bottlenose dolphins and harbour porpoises are also sighted in the river.
The Thames Barrier was built in the 1980s to protect London from storm surges and high tides from the North Sea. It is closed to tides several times a year to prevent water damage to London's low-lying areas.