Tongham Pool was formed through gravel extraction for the construction of the Blackwater Valley Relief Road (A331), which runs along the east side of the site. Since then the Blackwater Valley Countryside Partnership have worked
with Surrey and Guildford Councils to restore the site to an area which has public access and features for nature conservation. The River Blackwater forms the western boundary of the site.
The shallow lake margins are ideal for wildfowl and various water plants. The site is also populated by damselflies and dragonflies.
Whilst being dug for gravel, the remains
of a number of Iron Age hut circles were found. This indicates that quite a large agricultural settlement once existed in the fertile River Valley.
A particularly important find was an almost intact "log ladder" in the bottom of a well.
See also the map of the Valley