Skip to main content
Open Search Modal

Nature recovery for Thames, but river at high risk from sewage and climate change, report finds

A report published today is providing the first full ‘health check’ of London’s famous river in 60 years.

The State of the Thames Report, led by ZSL (Zoological Society London), is the first complete ‘health check’ for the river, using 17 different indicators of environmental health. It reveals positive news for wildlife, and ecosystem recovery, but warns of the threats from industrial and sewage pollution, as well as climate change.

The landmark report, which was funded by the Royal Bank of Canada as part of their RBC Blue Water Project® saw experts from 16 organisations demonstrate what has changed for the Thames since it was declared ‘biologically dead’ in 1957.

ZSL Conservation Programme lead for wetland ecosystem recovery, Alison Debney said: “Estuaries are one of our neglected and threatened ecosystems. They provide us with clean water, protection from flooding, and are an important nursery for fish and other wildlife.  The Thames estuary and it’s associated ‘blue carbon’ habitats are critically important in our fight to mitigate climate change and build a strong and resilient future for nature and people.

“This report has enabled us to really look at how far the Thames has come on its journey to recovery since it was declared biologically dead, and in some cases, set baselines to build from in the future.”

Having supported the work of ZSL for many years, the company building London’s new super sewer has welcomed the report. Liz Wood-Griffiths, Head of Consents at Tideway said: “This report comes at a critical time and highlights the urgent need for the Thames Tideway Tunnel, known as London’s new super sewer. The new sewer, which is due to be complete in 2025, is designed to capture more than 95 per cent of the sewage spills that enter the River from London’s Victorian sewer system. It will have a significant impact on the water quality, making it a much healthier environment for wildlife to survive and flourish.”

Highlighting the impact of dedicated conservation efforts, the report shows an overall bright picture for nature, with evidence of an increase in natural habitats such as carbon-capturing saltmarsh, birds and marine mammals. But it also highlights a long-term increase in nitrate concentrations, with sewage and industrial pollution identified by the Environment Agency as the main source.

The Tidal Thames supports over 115 species of fish, 92 species of bird and has almost 600 hectares of saltmarsh which is a crucial habitat for a range of wildlife. For the nine million people living alongside it, it also provides drinking water, food, livelihoods, and protection from coastal flooding.

Download the full report here and visit to find out more.