[3] An area of 181 hectares north of the causeway which divides the reservoir is the Pitsford Water Nature Reserve, which is managed by the Wildlife Trust for Bedfordshire, Cambridgeshire and Northamptonshire.

Holcot bridge was drowned when it filled and was replaced by a causeway a quarter mile further south.

This is the largest body of water in the county, and is used by wintering wildfowl, including the northern shoveler in nationally important numbers.

The Pitsford Water brown trout record was set in October 2017 by season ticket holder Bob Collins with a fish of 15lb 8oz.

There is public access to the water park, and a permit from the fishing lodge is required to visit the nature reserve.