Top left we have the 1887 OS map of the site of the present Forest Works, which as you can see on the map was originally a brick yard with the clay pits accessed along the edge of the reservoir. Top right. I took a spade along and dug back the topsoil on this drainage channel just up from the Forest Works. The clay deposit can clearly be seen. Left we can see on this geology map the stretch of clay deposit running along the Maun Valley from its rise at Kirkby. Without the clay there would be no reservoir as the limestone bedrock is porous. Infact the task of excavating the 72 acre reservoir site and lining the base with clay took nearly 2 years to complete.
Left. Note the clay deposit at the Sookholm site on the River Meden at the top of picture. Here the Romans built a tile kiln. Maybe a Roman tile kiln existed near Kings Mill by the Maun on the clay deposits hence the 3rd century coin hoard found just a few hundred yards away.