After extending the reservoir to allow for settlement, the precipitation engine house (PEH) opens. Dumping of raw sewage into the river ceases and sludge vessels, also known as Bovril Boats, took the sewage out to sea. Between 1887 and 1977 seventeen boats were built including Bazalgette and Sir Joseph Bazalgette. In 1990 the practice was banned following concerns that the sewage was contaminating beaches and affecting fishing stocks.
Population of London now approx. 3.8 million.