Tatton Mere
When you refer to ‘the lake’ in Tatton Park I know you mean the one by the Knutsford Gate known as ‘Tatton Mere’ but there are actually two different lakes separated by the estate road.

Tatton Mere began life as a moderately deep valley after the ice sheets retreated from Cheshire. A river ran down the valley and was blocked at some time in the distant past to form a ‘mere’. This was then also enhanced by landscaping in the park and to create a water supply for mills further along the water course at some point, probably in Medieval times.

The raised dyke that runs along the lakeside contains reused building debris which may indicate that it was constructed by William Egerton in 1791 when he demolished the village of Tatton Green which stood opposite the Old Hall and undertook major landscaping. Finds from the bank point to this period for its construction. It is a flood barrier and probably relates in some way to the lower lake (Melchett Mere) across the road opposite.

Legend has it that this lower lake was formed in fairly recent times by a massive underground collapse of some kind. One day park land – the next a lake! This has happened elsewhere due to mining activities and natural subsidence and this type of lake is often termed ‘bottomless’. The collapse which formed the lower lake probably related to water eroding the underlying Cheshire salt deposits over thousands of years.

In reality I do not know the depth of either lake, but nearby Rostherne is the deepest mere in Cheshire at over 160ft., and those at Tatton probably not much shallower than this as they are basically part of the same ‘chain’.

I hope this answers your questions.
Yours sincerely
Mark Olly