Presented by Richard Buchanan, Secretary of the Blackheath Scientific Society

Richard will present a talk first given by Steve Colclough of the Institute of Fisheries Management. He will speak about the decline and recovery of the water quality of the River Thames and the return of fish, birds and other wildlife. He will describe how the growth of industry, the increase in population and the use of flushing toilets caused pollution of the river. The Great Stink of 1858 set off the process to clean up the Thames. Richard will explain how the development of Joseph Bazalgette’s sewer system reduced effluent entering the river in central London; how subsequent improvements culminating in the building of the Thames Tunnel to intercept London’s storm water outfalls, have contributed to the recovery of the River Thames.

We will hear of the development of a fish survey programme for the Thames Estuary, the introduction of trawling limits in the Thames to stop fishermen trawling above Gravesend to protect stocks of young fish. We will learn about the more environmentally friendly design of river walls, the heightening of the river walls because of rising water levels of the Thames, the reinforcement of the foreshore that will favour fish habitats and the monitoring by volunteers of the Thames ecology with an App to collect data.