drying aquifers are threatening the very
survival of human civilization I hear
about this everywhere I travel all over
the world in cities and in farmlands
Wells are drying up as water tables drop
from overuse and changing rainfall
patterns but we know how to fix this so
in this video I'm going to lay out the
basics of how to regenerate a drying
aquifer so you can get started before we
talk about fixing the aquifer we need to
cover some basic geology and hydrology
to understand the situation beneath the
ground you need to realize that geology
is extremely variable and there are a
lot of anomalies out there but in
general there are three main types of
aquifers and the first one is called a
perched aquifer a perched aquifer is
caused by a layer of impermeable rock
strata that's set higher up in the
landscape than any other larger water
table the air area above the perch is
where the water comes from that feeds
this aquifer and a lot of times that
water will surface on the ground in the
form of a spring did you ever see a
spring popping out in the middle of a
hill probably from a perched aquifer
the next type of aquifer is called an
unconfined aquifer an unconfined aquifer
is created by all of the water in a
watershed that seeps into the ground and
settles in the low areas an unconfined
aquifers recharged by rain and snow and
basically follows the Topography of the
land so at the bottoms of valleys are
where we usually find the unconfined
aquifer close to the surface an
unconfined aquifer is connected to
streams and rivers and wetlands in The
Valleys the rivers are the part of the
aquifer that shows itself above the
ground this is how over pumping of the
unconfined aquifer can dry up rivers and
streams
the third type of aquifer is called a
confined aquifer confined aquifers have
impermeable Rock layers both above and
below so they're not recharged by the
rain falling above them if they're
recharged at all it's by lamb that's
probably far away and not related to the
surface topography see the water in
confined aquifers was deposited there a
long time ago and may have just been
sitting inside the confinement of rock
layers for hundreds or thousands or
hundreds of thousands of years water
that's been confined for a long time
like this is called fossil water I made
a whole video about the largest area of
fossil water on the planet in North
Africa where some of the same water has
been sitting right there in the ground
for a million years these Pockets can be
pressurized and when a pressurized
pocket is drilled into the water just
erupts out of the well without a pump
these are called artesian wells one of
the main differences between the perched
and unconfined aquifers with the
confined aquifer is that the perch and
the unconfined aqua offers are renewable
meaning that the water from the
Watershed soaks in and recharges that
aquifer but a confined aquifer is
non-renewable now it may possibly be
recharged by an area far away but it's
not recharged by the land above it so if
you're pulling your water from a
confined aquifer this video is not going
to help you very much where I lived in
Prescott Arizona the entire water supply
was pumped in from a confined aquifer
filled with fossil water that had been
deposited there during the pleistocene
era when it was a much wetter place
as the town grew and the water level
dropped without any recharge their
solution was to build a pipeline to take
water from an even farther away confined
aquifer of ancient water
you can guess how that one's going to
play out in the long term so as far as
groundwater recharge we're going to
focus on the perched and the unconfined
aquifers for these aquifers work can be
done within the catchment Basin which is
the land above these aquifers to rebuild
these water tables in a degraded
landscape with bare naked soil water
falls on Hills and Valleys and quickly
rushes through the drainage system
without soaking in to feed the
groundwater Supply if water in this
Watershed is not percolating into the
ground then when water is sucked out of
the aquifer by Wells it's not being
replenished in a massive restoration
project on the Los plateau in China they
described how to dress that bare naked
soil by putting on clothes first this
means putting a hat on the tops of Hills
by planting trees when hilltops are
wearing a hat and covered with trees
there are a lot of positive effects for
the hydrology as the forest canopy
breaks the force of falling raindrops
and creates a spongy Shady soil
environment for increased percolation of
water
I have an entire video on why hilltops
should grow trees so please watch how
trees make water
for a perched aquifer the hilltop May
comprise the entire catchment so the
effects of foresting the hilltop can
mean a dramatic increase in water
flowing from Springs connected to that
aquifer the next item of clothing to
dress the bare soil is a belt this is
the treatment for mid-slopes some sort
of structures or cultivation patterns
that are placed perpendicular to the
flow of water will create checks to slow
and sink the flow as the water moves
down slope
these can be Terraces rows of trees and
shrubs swales the tillage pattern
perennial grasses or any sort of
treatment to the slope which spreads the
water across the hill instead of flowing
down this interception will slow spread
and sink water for increasing
percolation by increasing the time and
surface area contact between land and
water the longer the water lingers and
the more ground it's spread over the
more time and space it has to soak in
small ponds or Terraces within the
drainages can further sink in excess
runoff and then the waterways should be
vegetated as much as possible so plant
roots grow deep to Aid with percolation
and shade the waterways to keep the soil
spongy the final item of clothing to
include are the shoes the shoes are
ponds placed at the bottoms of slopes to
collect any excess runoff that makes its
way past a hat and belt the ponds can
allow for further percolation and also
can be sealed and used as irrigation
water for Downstream Farmland so do you
see what we did
we slowed the flow of water throughout
the total Watershed by dressing the
terrain so water will percolate into the
ground and recharge the aquifer instead
of rushing off Downstream over bare
naked ground
recharging a depleted aquifer is as
simple as changing the duration of time
that it takes for water to move from the
top to the bottom of the Watershed and
giving it opportunities to percolate
instead of running off in order to
successfully recharge an aquifer you
need to control as much of the Watershed
as possible because the more widespread
your treatment is over the total
Watershed the more the cumulative
effects that your work will have on the
aquifer now I've been showing sloped
land but the same Theory goes for
flatter areas as well as urban areas
making places for water to soak in and
percolate throughout the entire
catchment that feeds the aquifer that
may mean small basins collecting Road
runoff or dry Wells to get water into
the ground in very dense urban areas
it's about intercepting water as close
to where it falls as is possible and
getting it down into the ground it's
really pretty basic because most aquifer
depletion is a result of land
degradation and urbanization there's
also the problem of over extraction
where people are growing thirsty crops
and building thirsty cities and pumping
down the aquifer faster than it will
have ever been capable of recharging the
solutions for that are based more in
water conservation growing appropriate
crops and regulating to prevent over
extraction the scale and complexity of
some of these situations may seem large
and overwhelming
but with large-scale aquifer depletion
we just need larger scale Watershed
restoration
what are we waiting for