Falls immediately downstream of karst
This location provides a unique opportunity to see water
literally flowing from stone! In very general terms, a karst spring
is the outlet for an underground "watershed". Water from lakes,
sinkholes, sinking streams, snow melt and rain goes underground and
flows through subterranean channels.
Karst is the term applied to areas where surface water seeps
into tiny cracks and fissures in the underlying rock (usually
carbonate rock, such as limestones and dolostones) and then
dissolves it. Carbonate rocks are relatively soluble in water that
is slightly acidic on account of dissolved carbon dioxide.
When the seeping water eventually finds an outlet, tiny
underground streams start to flow. Over time, as water volume and
speed increases, extensive dissolution of the rock leads to the
development of subterranean channels. These conduits range in size
from slightly enlarged cracks to tunnels many meters in diameter
and many kilometers in length. Karst springs occur where the
groundwater flow discharges from the conduit. Some Karst springs
are "cave springs", with large openings discharging very large
volumes of water.
A karst aquifer groundwater basin may have little relationship
to surface watershed boundaries. Karst hydrologists attempt to
determine the sources of Karst springs by water tracing; water
tracing usually involves injecting a tracer chemical into a
disappearing stream or other water source. Water samples from the
spring are tested for the presence of the dye. Alternately, packets
of activated charcoal are placed in the spring and later retrieved
for laboratory testing for the presence of the dye.
This particular Karst spring was "discovered" by Dean Marshall,
then foreman of Spray Lakes Sawmills, in 1967, while making a
preliminary study west of Marushka Lake. Since then, as best we can
determine, no successful water tracing has been done for this
Karst. Speculation as to the source for this Karst spring include
the valley between Mt. Shark and Tent Ridge and two deep lakes in
the basin west of Smuts Pass. In either case, it stretches the mind
to think of all this water flowing underground, possibly passing
under Mt. Shark over distances of up to 6 km before resurfacing
here.
In granting permission for this earthcache, Alberta Parks and
Recreation asked us to convey that all geocachers must stay on the
designated trails and that no items are to be removed or left at
the site. Also note that if you are wanting to do research on this
site (including water tracing with dye), a Research and Collection
Permit is required. If you're interested in pursuing further
research, send us an e-mail and we'd be happy to provide you with a
contact name and telephone number at Alberta Parks and Rec.
To claim your find, please e-mail your answers to the following
questions to the cache owner:
- As proof of visit, how many screws / bolts have been used to
fasten the information sign to its supporting post?
- Estimate the width of the vertical rock wall along the back of
the pool.
- Carefully observe the surface of the pool. You should be able
to locate more than one outlet from the karst aquifer. How many did
you see?
In your online log, feel free to describe your visit to Watridge
Lake and Karst Spring and to upload your best digital photo(s) from
your visit but please ensure any photos do NOT show the details
necessary to log this cache.
SOURCES: Information plaque at Karst Spring; Kananaskis Country
Trail Guide, Third Edition, Volume 1 by Gillean Dafferns; “Karst
Hydrology” by George H. Shaw in the Water Encyclopedia on the
internet
here; Kentucky Geological Survey’s “Introduction to Karst
Groundwater” on the internet
here.