Hydrology of eastern Mendip showing stream sinks, springs and tracer
test flow paths. The largest springs are named.
By placing the dye in a stream sink and seeing where, and how long
it takes until the dye reappears at one or more springs, coupled with
direct exploration by cavers and cave divers, the underground drainage
pattern of the region can be deduced. Over the past forty years,
numerous tracer tests have been carried out by cavers, university
academics and water companies in an effort to understand the underground
The underground streamway in Stoke Lane Slocker.
A stream sink, Stoke Lane Slocker, Stoke St Michael. The water reappears
at St Dunstan's Well, over a kilometre away. Photo. A. Farrant.
The resurgence. St Dunstans Well, Stoke St Michael. The water from
Stoke Lane Slocker emerges from the left hand side of the fenced
enclosure. Photo. A. Farrant