The people's voice. [volume] (Helena, Mont.) 1939-1969, 1948-10-15
Conclusions From An Engineering Study Of Missouri Valley Development

End Installment Continued from last week
In May, 1914 necessary flow for 125 days OF
non-navigation reported by Army Engi
$500 cubic feet per second or 1,3640OC
acre feet at Yankton. Total requirement for the
navigation channel is therefore, 15,645, 900 acre
feet of water per year, fixed by Army Engineers
Several checks have been made on these figures
While think the non-navigation season flow
might be reduced from $500 to minimum of 5000
cubic feet per second, find that the navigation
season flow of 10000 cubic feet per second at
Yankton is nearly accurate possible
%. In addition to revetments, pile dikes, and
other channel improvements, flood control plans call
for series of earthen levees from Sioux City to
mouth of the river of these to be closer than
400 feet to the channel; with a flood plane width
between levees opposite sides of the river, of not
less than 5000 feet at Sioux City and 5000 feet at
the river mouth. Estimated cost of these levees is
S108,900, 600, and this system will destruc-
ton of about 225,OOO of aluvia bottom lands
Conflict, Basic Error, and Shortcomings
PicIs-Sloan Plan
One irreconcilabe conflict and one basic error
in the Pick-Sloan plan lead to several serious and
rremediable shortcomings The Importance of
these may be listed
20. The conflict is between water for irrigation
and other consumptive uses in Montana, Wyoming,
and the two Dakotas and water for navigation below
Yankton Irrigation of g. 709, 663 of presently
listed land restoration of Devils Lake, reservoir
evaporation, and the navigation channel will require
about 23,S19,750 feet of water yearly. Aver
age annual flow at mouth of the James River Gm-
mediately below Yankton) is not apt to average
than 1862, 900 acre feet yearly With no
provision for other upper valley cOnsumptive uses,
there will be shortage of 5177750 acre feet per
year. If Engineer Soans plans for upper valley
water fully carried out, there will be flow
for 9-foot channel and shortage of about 400 600
feet per year for even a 6-foot channel. If
the 9foot channel is supplied, less than 10000
acres Of land in the upper valley will be benefited
by irrigation.
80. Protection of lower Missouri valley from
floods is undoubtedly the first essential of any sound
development plan. There is basic in the
Pck-Soan plan. Instead of taking all possible
water (about 65 per cent at Yankton South Dakota,
and 43 per cent at Hermann, MissourD off lower
valley flood sufferers by maximum consumptive use
above the plan pours all possible water down into
the lower valley. 1t does this in about the worst
possible way 1t holds back by storage 81 per cent
more, of necessary navigation channel flow for
release from March Is to November Is. One-half
of this period is also the time of floods This pour
ing of extra water down into the lower valley during
period, one half of which is critical, and the
struction of $50 mile series of double bank levees
to minimize destruction does not appear basically
sound.
81. After making deductions for necessary wa
ter uses below Yankton, all irrigation proposed
by Pick-Sloan plan above that point all reservoir
evaporation, ground water restoration effective
soil conservation program, and for per cent
avodable waste of irrigation water, there appears
to remain sufficient supply to irrigate 3,885000
acres of additional land. Such land is available for
irrigation and within reach of water supply. 1t
thus appears that the presently proposed navigation
channel not only denies about 5000, 900 acres now
listed for irrigation in the upper valley, but denies
additional 1886 900 acres that and should
ultimately be irrigated Total lands benefited, in
Guiding about 500, 900 for supplemental water
can slightly exceed 100000 acres in the whole
valley under full development plan
80. Listed generator capacity implies about g.
0000 600, 900 kowatt hours Of power annually under
the Pick-Sloan plan Three-fourths of this capacity
is to be installed at main stem reservoirs which will