WSP10994

• File Number: 8210.470
• Description: Pacific Southwest Interagency Committee
• State: CO
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 3/1/1962
• Author: PSIAC
• Title: Stock Water Facilities Guide - March 1962
• Water Supply Pro - Doc Type: Report/Study

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has the added advantage of permitting the selection of flow periods when
the sediment load is low, thus preserving the pond capacity.

Springs

In general the larger perennial spr ings are in the same category
as perennial streams since most have long since passed into private own-
ership and their v"lue to outside development is thus sharply limited..,
However, a few have been designated as public watering places and, in
some cases, use of these sources is being expanded by hauling or distri-
bution by pipeline. Springs have an advantage in this regard because,
unlike streams which generally occupy the lowest parts of the basin, they
often are located at relatively high elevations favorable for gravity distri-
bution by pipeline.

Although most major springs have been fully appropriated, it is
obvious from observations over the Southwest that many springs are
improperly or inadequately developed. Tolman (1937) states that only a
small proportion of the world's springs are developed to the ir full capacity,
and that in semiarid and arid regions springs are rarely fully developed.
Evidence supporting the se statements is the phreatophyte growth, gener-
ally worthless, associated with most springs. A rough estimate of the
water wasted in this manner can be derived by measuring the ar'ea of
swamp and plant growth and appl ying an appropr iate coeffic ient of us e
by evaporation and/or transpiration. Experience indicates that the waste
from most small springs, ,estimated in this manner, often exceeds by
several times the flow left for beneficial use.

The small yield requirements of a properly developed range stock
water facility'make it possible to consider sources, such as minor
springs, that would be valueless for other purposes. It is a generally
accepted rule in most ar id and semiarid areas that no more than 100 head
of cattle, or equivalent in other types of stock, can be grazed for any pro-
tracted period within the service area of a single water facility without
exceeding carrying capacity and causing damage to the range. On poorer
ranges the number may be considerably less and on better ranges it may
be exceeded for short periods, but even on the best range the limitation
of 100 seems to be generally accepted. The actual drinking requirement
for 100 head of cattle is approximately 1,000 gpd (gallons per day) equiv-
alent to a continuous yield of O. 7 gpm (gallons per minute). The require-
ments for larger herds will be in direct proportion to the number, but as
can be seen, a herd of 300 needs a yield just slightly in exc."'S:s of 2 gpm.

Relating a yield of this magnitude to transpiration losses from
phreatophytes or to evaporation from damp or swampy ground shows that

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