Vegetation follows the baulks of the flooded clay, not gravel, pit. Most pits in these parts are dug for gravel, the Manea Pit was dug for the re-enforcement of the banks of the washes.
From the Manea Pit Management Plan 2015:
“Local information points to the Manea Pit being developed in the 1930s, by the predecessors of the Environment Agency, as a source of clay to repair or improve the flood embankments along the Ouse Washes. The 1980 Geology Map (Ely sheet 173 published in 1980) identifies the clay as Jurassic Amptill Clay.
The 1927 edition of the 6 inches to 1 mile Ordnance Survey (OS) shows an undeveloped field in the location of Manea Pit. The 1950 edition of the OS map shows the Pit to the current extent and with a “tramway” track built around the north, north-east and south-east side of the Pit and down to the Ouse Washes banks along what is now the footpath.
In the map within the 1973 Manea Village Draft Plan, Manea Pit is identified as a “Cambient reserve”, which was a wildlife designation that pre-dates the County Wildlife Site designation in Cambridgeshire.
These maps confirm the local information on the approximate date when the pit was dug for clay and that it has had some wildlife interest going back to at least 1973, approximately 40 years.
In recent times the Pit was rented out to a Fishing Club. There was little management of the vegetation and much of the site was overgrown with little public access. The strip of land to the South-east of the open water (now developed as the orchard and wildflower meadow) was rented out for agriculture.
In 2008, Manea Parish Council purchased Manea Pit from the Environment Agency, on a 999-year lease. Within the lease there is a clause requiring the Parish Council to manage and promote the land for informal public recreational, educational and conservation use.”
The more you look the more you see.