London river was declared 'biologically dead' in 1957; decades later it is filled with sharks and seals

The River Thames in London has made a remarkable recovery, evolving from a biologically barren stretch to a vibrant ecosystem full of life, such as sharks and seals. This revitalization is attributed to decades of pollution management and enhanced sewage systems. The Thames Tideway Tunnel plays a crucial role in minimizing sewage discharge. However, challenges like warming waters and nitrate pollution still pose threats.