Isleworth Ait

Isleworth Ait is a London Wildlife Trust nature reserve, and is a teardrop-shaped island in the River Thames in England, between 3.5-hectare (8.6-acre) and 9.370-acre (3.792 ha).

[5][6] Isleworth Ait was once a centre for the production of osier - a willow which used to be harvested on the island to weave baskets to carry fruit and vegetables grown in Middlesex to the markets in London.

Thames Water owns the island, which houses the outfall from the Mogden Sewage Treatment Works draining outer West London plus Wraysbury and Spelthorne – effluent of more than 2,000,000 residents in all.

The Mogden works, which is a consolidation of many across its catchment, for a complete approach towards cleaning London's main watercourse, is being upgraded from the late 2010s to the early 2020s after billions of litres annually of untreated outfall from the island.

[7][9][10] The Metropolitan Water Board bought the ait from the Duke of Northumberland in the 1930s; visitor access is granted to local volunteers of the London Wildlife Trust.