Bazalgette's work ensured that sewage was no longer dumped onto the shores of the Thames and brought an end to the cholera outbreaks; his actions are thought to have saved more lives than the efforts of any other Victorian official. His sewer system operates into the 21st century, servicing a city that has grown to a population of over eight million. The historian Peter Ackroyd argues that Bazalgette should be considered a hero of London.