The Lamar register. [volume] (Lamar, Colo.) 1889-1952, 1910-10-19
VALUE OF RESERVOIR
Probably Most Important Adjunct
to Windmill Plant.
In Many Instances II Can Be Made
Source Of Profit in Winter Months
for Producing Iee-Size and
Shape Are Essential.

Probably the most important ad-
1unct to a windmill plant is the reser-
voir. Indeed, a means of storing
water which is delivered at a small
rate of flow should be resorted to in
every instance where the flow is less
than 500 gallons per minute. The
reason for recommending a reservoir
for flows up to this amount is that,
with small streams used direct from
the pumps. the loss in conveyance in
bitches is excessive and the loss in
the application of the water to the
land is large. since a small stream
VIII saturate a spot and a large
amount of water will sink into the
soil In this one place instead Of
spreading over a large area and moist
ening the surface. Further. much
more labor is required to irrigate with
small stream than with a large one.
If climatic conditions were favorable
and resources not limited. there would
be an advantage in having a reservoir
which would hold all the water
pumped from the time irrigation stops
in one season until it begins in the
next. for It is during the winter
months that the greatest winds occur
Operation during the winter months
would require only a large reservoir
and the draining of pipes during calm,
cold days or. better still. frost-proof
housing for the pump and piping. In
many instances a reservoir can be
made a source of profit during the
winter months by producing Ice.
The size and shape OF a reservoir
are important. A circular reservoir
contains about 10 per cent. less shore
line than square reservoir of equal
area. and the surface of the water is
less exposed to winds when the reser-
voir is partially filled. An oblong
rectangular reservoir with one of its
short sides toward the prevailing wind
may have smaller shore line ex-
posed to wind. but 1t has a greater
shore line. varying from 10 per cent.
up. depending upon the ratio of sides
to ends. and in view OF the fact that
the seepage Of water through the
banks is approximately 20 per cent
of the loss in the bottom of equivalent
area 1t is desirable to reduce to q
minimum the length of embankment.
What has been said concerning shore
line applies to the wave cutting of
banks also. Round reservoirs in all
sizes are more simple to construct.
In orchards rectangular reservoirs
conform better to the layout of plats.
which are usually In squares or rec
tangles; but this does not Offset the
many advantages of the round ones.
The reservoir should be of sufficient
size to hold the water pumped be-
tween irrigations. II the period be-
tween irrigations is ten days. and the
pump delivers 60 gallons per minute
on an average. the quantity pumped
would $4,000 gallons, or lis. 500 cubic
feet. The reservoir at Cheyenne lost
about 10.5 per cent. of its capacity in
ten days. but this is not representa-
tive of earth reservoirs. which may
lose so per cent. in ten days. Assum-
ing the loss to be 25 per cent, the
capacity required would be s6.625
cubic feet. Just little less than two
acre-feet. The reservoir should have
some additional capacity to provide
for the water pumped during n few
days II irrigation is postponed for any
reason.