Hedgecourt is a 33.6-hectare (83-acre) biological Site of Special Scientific Interest (SSSI) north of Felbridge in Surrey.

There are wetland breeding birds such as water rail, mute swan, sedge warbler, kingfisher and tufted duck.

Its primary inflow and outflow are the Eden Brook and it has a catchment area of 9.73 km2 (3.76 sq mi), of which around 60% is agricultural land and 23% is urban.

The surface area is 17.2 ha (43 acres), the maximum depth is 1.25 m (4 ft 1 in) and the mean hydraulic residence time is 83 days.

[5][6] A local angling club stocks the waters with fish and Surrey Wildlife Trust rents 5 ha (12 acres) at the west end as a nature reserve.

Aquatic plants characteristic of hyper-eutrophic conditions, such as Stuckenia pectinata, Potamogeton pusillus and Zannichellia palustris, were found to be abundant.

Where the ground is waterlogged, species such as marsh horsetail, yellow loosestrife, reed canary-grass, gipsywort, meadowsweet and meadow thistle are found.

[15][16] Local legend holds that the mill supplied nails for St Paul's Cathedral in the late 18th century.

[15] It was bought by McGuran and Quest Inns Ltd in the summer of 1987, but during refurbishment works the following March, a fire caused extensive damage.

In the early 1990s, it was possible to see the framework of the iron water wheel attached to the rotting wooden axel shaft.

[4] The main lake was purchased by Crawley Mariners Yacht Club in 1977; the cost was part-funded by a £10,000 grant from the National Sports Council.