The term “Artesian Well” is named for the former province of
Artois, France, where many such wells were drilled by Carthusian
monks since 1126. This technique was also known much earlier in
ancient Syria and Egypt. It is unknown whether the monks of Artois
learned of this technique from outside sources or developed it
independently on their own. This particular Artesian well is
frequented by locals who will fill up their vehicles with
containers before coming here to fill them with spring water, so be
prepared to wait in line.
Artesian wells sit atop recharging aquifers that can be very
large in size, spanning many miles across. Rainwater that is not
channeled as runoff (creeks, streams, rivers) slowly seeps through
porous materials and through cracks in otherwise impervious
material, moving downhill until its movement is blocked by a
completely impervious strata, where it pools and saturates the
surrounding porus strata. This happens underground in much the same
way as surface runoff flows downhill until its movement is blocked
and it pools to form ponds or lakes. This underground pooling of
water is what we sometimes refer to as the “water table”.
Sometimes this underground water is not under pressure, and so
must be hauled up by bucket (think back to the “wishing wells” of
your childhood) or pumped up to the surface for use. In a
recharging aquifer such as this, the water table at the recharge
zone is at a higher elevation than the head of the well. Also,
saturated, porous strata such as limestone or sandstone may be
trapped between layers of impermeable rocks and clay and slowly
crushed. This constant pressure squeezes the water, so that when it
finds an escape route (Artesian well) it defies gravity and flows
up out of the ground without pumping. This can be modeled by
filling a plastic baggie with water, placing a straw though the
opening into the water, and taping the opening closed around the
straw. Squeeze the baggie to force water up and out through through
the straw.
Artesian wells have been very important to man as he settled and
developed this country, as they offered a reliable source of clean
water for drinking and irrigation. The water is filtered after
travelling through many miles of porous sand and rock, in a process
that probably took many, many years to complete. This filtering
removes most of the pollutants that plague most surface runoff
waters today. The readily available clean drinking water not only
helps give birth to towns and cities, but also to entire
industries. Witness Kentwood Springs bottled water, located a few
miles south of here in Kentwood, LA. The waters of this spring come
from the Kentwood Aquifer system,, in contact with the Citronelle
Formation and the alluvium of nearby major rivers (Mississippi and
Pearl). These sandy layers are bordered by layers of clay that
restrict but do not prevent vertical movement of the water through
the underground strata. Precipitation (rain) is the principle
source of recharge for this system, and the higher elevations in
south Mississippi are the principle recharge zone.
To take credit and log this find, you must do the following: 1.
Take a photo of yourself with your GPSr, with the well in the
background. Post the photo with your log. 2. Estimate the flow of
the well in gallons per minute. Do this by filling a container of a
known size, recording the time it took to fill the container, then
calculating the flow in gallons per minute. E-mail the flow to me
via my contact link above.
Logs without the required information will be deleted. Please do
not post your answer to #2 with your log. I hope you learned
something about Artesian wells today, and enjoyed this
earthcache.
Congratulations to Steenroller for FTF on this
cache!
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