The star-independent. [volume] (Harrisburg, Pa.) 1904-1917, 1914-11-20
YUKON river ONE OF THE
Greatest ON CONTINENT
Fifth Place Among Large Rivers of
North America - Flow Ranges
From 10000 to 2oi,0OO Cubic
Feet of Water Second

Washington, Nov. 20.-The Yukon
river in Alaska is one of the great
rivers of the North American contin-
ent. brief report on the discharge
of the Yukon river at Eagle, Alaska,
bv +. A. Porter and K. w. Davenport,
has Just been issued by the United
States geological survey as water sup
ply paper S45-F. Probably few people
have an adequate conception of the
size of this river and characteristics
of its flow. A. H. Brooks, of the geo
logical survey, gives the Yukon fifth
place among the large rivers in North
America and estimates its drainage
area at about $4,000 square miles.
Its length, including the Lewes and
Teslin rivers, is given in the report as
5000 miles. This may be compared
with 5000 miles for the Mississippi
and Missouri, 2,S6S miles for the
Mackenzie, 1000 for the Colorado
combined with Green river, and 1900
for the Ohio combined with the Alle-
gheny.
The discharge of the Yukon varies
from a maximum of 200 TO a mini
mum of 10,100 cubic feet a second, or
an estimated average flow of 1920
cubic feet. This is 4 relatively small
discharge, the average flow Of the Mis-
sissippi being $4,000, that of the
Ohio, 100000, and that of the Colo
rado 2S,S00 second-feet. The Nile, with
a drainage area of 1,262,000 square
miles, has an average flow of $1,000
cubic feet second The flow of the
Yukon is therefore relatively small as
related to its drainage area, and this
apparent anomaly is accounted for by
sthe fact .flht the interior Of Alaska
has the small rainfall characteristic
of that portion of the United States
which lies between the Sierra Nevada
and the Rocky mountains, north of the
latitude of Salt Lake City
Navigation on the Yukon has so i'm
portant a bearing on transportation
in interior Alaska that it has given
rise 70 a general recognition of two
seasons-the "closed season." when
the Yukon is either filled with floating
ice or frozen over, and the 'open sea-
son. The breakup of the ice usually
occurs about the middle of May, after
which the river is open to trsnsporta
tion for five or six months. or little
longer. The breakup is not only an
event of great economic significance to
the inhabitants in the interior of
Alaska, but it presents features OF
great dramatic interest as well. One
who has witnessed it, according to
the authors of the survey report, can
hardly imagine the impressiveness of
the spectacle. From bank to bank the
surface of the river is a solid mass of
huge moving ice cakes, which are con-
stantly grinding and disintegrating
with an awe-inspiring exhibition of re-
sistless force.
The freeze-up is less spectacular,
With the increasing cold of the au-
tumn slush ice forms in the river and
as the cold becomes more intense the
ice increases in volumn until finally
it is sufficient to bridge the entire
stream. This means the termination
of navigation on the Yukon until the
following May.
The Geological SURVEYS measure.
ments of stream flow near Eagle were
made during the winter at point
about 2 miles above the town. where
the river is 1900 feet wide, by cutting
holes through the ice at intervals of
so feet and making soundings. In
this way the exposed section of the
river was determined and the velocity
of the stream at each hole was deter.
mined by Price current meter. Dur
ing the period Of breakup discharge
measurements were made by means of
ice floats. In the open season the flow
was determined by the same method
as on any large river.
The maximum discharge measured
in 1911 was on May %, when the vol
ume was 253,000 second-feet. The
width of the water surface at the
measuring section was 1916 feet and
the greatest depth of the river was
2S.7 feet. The average surface velocity
was 5.S miles an hour.
A copy of this report may be OBJ
tanned on application to the director,
United States Geological Survey.
Washington, D. C.