| Site of Special Scientific Interest | |
 Channel of the River Stort before it was canalised to become the Stort Navigation [1] | |
| Location | Hertfordshire |
|---|---|
| Grid reference | TL490183 |
| Interest | Biological |
| Area | 17.3 hectares |
| Notification | 1986 |
| Location map | Magic Map |
Thorley Wash or Thorley Flood Pound is a 17.3-hectare biological Site of Special Scientific Interest in Thorley, south of Bishop's Stortford in Hertfordshire. [3] [4] It was formerly a flood pound for the Stort Navigation, which was decommissioned in 2004 and converted to a more natural state. It was purchased by the Herts and Middlesex Wildlife Trust from the Environment Agency in 2011. [5] [6]
Habitats include tall wash grassland, which is now rare, marsh and waterlogged grassland. It has a wide variety of plant species, including reed sweet-grass and meadowsweet. There are flowers such as fen bedstraw and early marsh orchid. Breeding birds include snipe and water rails. [3] The site also has the endangered Desmoulin's whorl snail, which is in the Red Date Book, together with diverse dragonflies, damselflies, birds, bats, small mammals and reptiles. [5]
There are five wooden sculptures by Daniel Cordell, commissioned by the Wildlife Trust in 2012. [2]
The Stort Navigation forms the boundary between Hertfordshire and Essex, and the site is on the Hertfordshire bank, but access is by a bridge from the towpath on the eastern Essex side. Access is restricted to footpaths due to the dangerous deep silt on the site.
