The Students of Delaware Valley College of Science.

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tired to dance. Rheingold ends their commercials with
its now famous tag line; "We must be doing something

Even detergent commercials, capitol offenders of the
capital eyes and ears, have begun to show a light touch.
Lever Brother's Breeze includes a towel as a premium
in its package. Most of its 60 second commercial is spent
showing a man breezing himself before the bathroom
mirror, snapping the towel about his shoulders. Presum-
ably, the wife is Breezing the dishes, but she never ap-

Are the new commercials a tasteful trend? Yes, but
with a big hedge. The fresh approach is appealing to
most people (some sales have increased as much as 20%),
but financially it remains out of reach for most people.
The fact that TV commercials are now being watched
with something like pleasure does raise the startling
possibility that TV might be upgraded by, of all things,
the long-abused commercial.

-Bud Hofstetter

A poem should be:

obvious and mute,

as a globed fruit.


as a flight of birds

equal to, not true

For all the history of grief

an empty doorway and leaf

For love

the leaning grass

two lights above the sea

a poem should be.

^et ^etcrnt

Richard J. Honielski

She came back to me today.

I didn't expect her to say:

"I've come back and forever I'll stay.

Next to you I'm lonely and small;

But in your arms— this feeling— is unforetold.

For I wish only that I can express it to every other girl

that I know . . .
The way in which you caress me in your arms.
They'll never have the chance to bestow."

Page Seven

The Importance Of Ground Water

David A. Stockbridge and Wayne M. Winner

What is ground water and how does it affect our
lives? It is the water from springs, the water pumped
from wells and the water that bubbles up through the
bottom of brooks, rivers and lakes.

Water is the life blood of the earth. It moves from the
oceans, to the atmosphere, to the land and back to the
atmosphere or the ocean. This unending circulation of
water is referred to as the hydrologic cycle. It goes
round and round in the water cycle, and we use the
same water again and again.

In its natural location, ground water is invisible to
human eyes. In most places, ground water occurs in and
moves through an intricate network of very small open-
ings. From the land surface down to the zone of satura-
tion, the soil contains both water and air. In ground
water terminology, this zone is referred to as the zone
of aeration. The zone in which all openings are com-
pletely filled with water is the zone of saturation. The
boundary between the zone of aeration and the zone of
saturation is referred to as the water table.

Ground water recharge depends principally on the
character of the soil and the slope of the land surface,
but it is greatly influenced by the management of water-
sheds. Whether water enters the ground or runs off
overland depends largely upon the nature and condition
of the soil and its vegetative cover. Water is essentially
an agricultural resource. The farmers and ranchers who
control our farmland, rangeland and woodland also con-
trol to an important degree the movement of water that
falls on their land.

Let us see how the water is held in the ground. There
are two groups of water bearing materials. The first is
a loose aggregation of individual grains, such as sand or
gravel. The second consists of compact, hard rocks re-
ferred to as bedrock. With ground water we are con-
cerned with the natural openings in these materials. The
size, shape and arrangements of these openings deter-
mine how much water the rock or soil can store and how
readily the water can move from one point to another.
The total volume of the openings in these materials de-
termines its storage capacity or porosity.

The amount of water in storage in the ground is
seldom appreciated. For example, an area of sand and
gravel, with a zone of saturation 500 feet deep with an
average porosity of 25 percent is equal in storage to a
lake 125 feet deep and of the same area. Underground
reservoirs contain more fresh water than all surface
reservoirs and lakes combined, including the Great Lakes.
Ground water storage is estimated to equal 10 years
average rainfall.

Ground water is not always readily accessible. At
least 85 percent of the land area is underlaid by ground
water, but the ability of the rock or soil to transmit this
water is largely dependent on the size of openings and
their degree of interconnections. Conditions are not al-
ways favorable for this.

The detention period of ground water in rocks may
in some cases be as long as 10,000 years. Most under-
ground water moves, though often very slowly, and

some is discliarged as spring and seeps or subsurface
flow in streams. The rate at which water will move
through a particular soil or rock determines whether the
material will supply water in a usable amount to a well
or spring. This rate generally must exceed 0.1 foot per
day to be considered "water bearing." Such a material is
termed an aquifer. Sand and gravel are excellent aquifers,
while clay and silt are not.

As in a surface reservoir, the quantity of water stored
underground fluctuates in response to changing rates of
inflow and outflow. Recharge from equivalent amounts
of precipitation is usually much less during the growing
season than during the winter, because during the grow-
ing season more of the water is lost by evapotranspira-
tion from the soil and vegetation, and less water infil-
trates to the water table. The U. S. Geological Sun-ey
has mapped the principal ground water reservoirs of the
United States. In many areas ground water is being used
faster than it is naturally replenished through the water
cycle. This may be the reason that water levels in wells
drop. For example, in the southern high plains, the rate
of pumping in the early 1950's was 30 to 50 times the
estimated recharge. In many coastal areas salt water is
replacing fresh water where overpumping has lowered
water tables to below sea level.

The occurence and development of ground water are
different for different rock units and different topo-
graphic situations. Where the sand and gravel deposits
are in hydraulic contact with a stream flowing through
the valley, pumpage may safely exceed the amount of
water reaching the deposits from direct recharge and
from the adjoining hills. The excess pumpage is sup-
plied by water that infiltrates from the stream into the
deposits. Stream infiltration is, of course, desirable only
where the streams are not polluted. The deposits through
which the water moves, from the streams to supply
wells, are generally able to eliminate or greatly reduce
bacterial pollution. However, the deposits have little or
no effect on most chemicals dissolved in the stream
water. The detergents, pesticides and herbicides that
reach the streams and underground waters from land
surfaces present a problem the magnitude of which is
not yet known.

Pollution of ground water is a much more serious
problem than stream pollution. The time required for
a stream to recover from the effects of the pollution
might be a long term, but the pollution itself is dis-
charged rather rapidly. If we pollute ground water, the
huge reservoir is ruined for generations. There isn't any
way to flush pollution from ground water supplies. In-
creased ground water development can also improve
water quality at times.

Disposal of wastes will continue to increase in the
future. Water from some wells has been found to foam
when agitated. The foam is caused by synthetic deter-
gents which have been introduced into the ground water
through septic tanks and cesspools. This serves as a
vivid indicator of sewage pollution. The solution to the
problem lies either in eliminating the sources of pollu-

Page Eight

tion or by installing sewers or by constructing a new
well in an unpolluted area or in a deeper part of the

The water problem is not one, but many. Nearly
everywhere there is a problem— too little or too much,
too soon or too late. Drought is a recurring hazard in the
Great Plains while drainage is a common problem in
the Coastal Plains.

Articles telling of a continuous long term decline of
the water table in part of the Western states have led
many people to believe that a similar decline is occurring
in the East. This is not the case. The Eastern water table
fluctuates up and down seasonally. But it is not under-
going any regional, continuous decline. However, it is
possible to pump water from the ground in any local
area at a rate faster than the water can be replaced,
thus lowering the water table.

Conservation needs inventories conducted by the
U. S. Department of Agriculture have shown a great
need for ponds. The number of ponds built by the Soil
Conservation Service is more than Vi million with an
average size of about 2 acre-feet.

Too much water is as serious a problem as too little
in parts of the country. Much of the land needing drain-
age for agriculture is not covered with water. Rather, the
soils are waterlogged, excluding air from the root zone
and making them unsuitable for growing crops.

Due to seasonal high water tables or springs and
seeps, farmers may be limited in the crops they can
grow and the time of tillage or cultivation. We have
worked with this type of problem and have assisted in
laying out drainage systems as student trainees with the
Soil Conservation Service. These drainage systems have
made possible more efficient use of farm lands. Farmers

are then able to work their fields earlier and raise such
crops as alfalfa which would not stand up under high
water table conditions.

Water problems are watershed problems. A watershed
is any area of land that drains into a particular stream
or body of water. The character and condition of the
land on which water falls influence its movement into
or over the ground. Land management effects the tim-
ing of the water's arrival to streams, lakes, or under-
ground reservoirs from which it can be withdrawn for
human use.

The aim of watershed management is to maintain
quality as well as to retain the greatest quantity of water
for use. Trees, grass and brush are nature's most effec-
tive ways to hold soil and facilitate water percolation
and water storage within the soil.

Water control and conservation cannot be separated
from soil conservation. Soil conservation districts include
95 percent of all agricultural land. Through these lo-
cally managed districts, individual landowners and
operators are putting basic soil and water conservation
plans into effect on their own land.

Ground water is one of the most valuable natural
resources used by millions of people in cities, villages
and rural areas all over our nation. The desirable fea-
tures, such as handiness, sometimes leads to undesirable
practices. Water is taken for granted and wasted without
thought of the consequences or the rights of others. It is
contaminated by sea water, industrial wastes and do-
mestic sewage. Our economy and way of life are based
on an abundant supply of cheap water. To best serve
the longtime needs of the people, each community must
conserve and manage the available water today to have
water tomorrow.


Online LibraryThe Students of Delaware Valley College of ScienceThe Gleaner (Volume v.66 no.1) → online text (page 2 of 2)