The Mankato free press. [volume] (Mankato, Blue Earth County, Minn.) 1879-1924, 1920-11-19
Baking VALLEY FLOODS
E. v. WILLARD TELLS HOW
THIS CAN BE DONE
Report Submitted BY Commits
sioner of State Department
Of Drainage r. ~

Prevention OF Hoods In the MINI
esota valley by the construction Of
impounding dams or reservoirs with
q total capacity of 1880, 0OO. 600 cubic
feet Of water Is recommended in the
report of the department OF floods
just completed, and which has just
been made public by E. V. Willard,
commissioner OF the state department
OF drainage and waters. This report
declares that a material reduction of
the devasting floods in the Minnesota
river valley Is possible, but some
lands must be sacrificed for the ben
etft Of the others. The estimated cost
Of the project Is placed at S2,0O0,O0O.
The report further states that no
substantial projection or the Mimi
ssota river valley lands from floods
can be accomplished by either levee
construction or channel improvement,
but that flood protection must come
and can be accomplished by the con
struction OF at least three reservoirs
or impounding dams.
Built At BIG Stone Lake.
The first OF these reservoir sites,
according to the report, would be
located at the foot OF Big Stone Lake,
with a 100000. 900 cubic feet Of stor-
age capacity. II is proposed TO locate
the second reservoir at the foot OF
Lac Qul Parle including Lash Lake
where a capacity OF 5000, 900 900 cubic
feet OF water could be stored, and the
Lac Qul Parle and Chippewa rivers
would be diverted into this reservoir.
The third proposed site for a reservoir
would be at the mouth OF the Cotton
wood river with capacity Of $500
900 900 cubic feet OF water could be
impounded. With the flood waters i'm
pounded in the proposed reservoirs.
the water could be released as fast as
the channel Below the dams would be
/ capable OF carrying Off the water
bank high. The report is strongly re-
commenting the construction OF res
ervoirs near the headwaters OF the
river, points out the fact that to pro-
fect the valley lands from all floods
would be improbable and prohibitive
tn cost, for channel Improvements Of
this nature would cost about $500 per
acre. II the valley were ten miles
WIDE instead OF one mile in width the
plan would be feasible, for then the
cost would be but $50 per acre. The
protection OF the valley lands from
frequent floods is possible by the res
ervoir plan, and Mr. Willard In his
report recommends the plan as being
worth twice what II will cost. The
best paying project is the one which
will protect the valley lands from all
floods with the exception OF those
which may reoccur once. say in from
fifteen Ito twenty years.
Some OF, The Conclusions
Some Of the conclusions reached in
the report are:-That although the
reservoirs proposed can not retard
ali of the run OF water during the ex-
IRENE floods. the structures them
selves must be able to meet extreme
flood conditions.
Practically all Of the low lands IN
the minnesota valley, aggregating
about one hundred thousand acres, are
now flooded at least every other year
on an average.
The flood protection works pro-
posed In the report will materially
benefit over sixty thousand acres of
land. Large additional areas will re-
ceive minor Benefits. This does not
include prairie lands TO which the
valley furnished ditch outlets.
The lands to be benefited lie:
Between Big Stone and Marsh lakes
between Lac qui Parle and Granite
Falls; between Minnesota Falls and
1 Fort Ridgely; between New Ulm and
Mankato and between Mankato and
Carver -ss.
The reservoirs are for flood pre-
yention and not for power purposes
or those of navigation, and according
| under a single system with that end
In view or full benefit will not be
derived from the project