Evening times-Republican. [volume] (Marshalltown, Iowa) 1890-1923, 1917-08-01
PLANS NEARING COMPLETION
ron DAM TO PROTECT CITY
!, SUPPLY MAIN.
BELL SAYS
COST MAY BE $1,000
Dam Bsins Planned Will Be Down
Stream From Water Main--6ank Ct
Stream Below Dam to Be Protsossd
by Retaining Walls Extending u
conersts Bridge in Center Street.

a The dam project the city expects 70
promote across the channel north Oh
the river to protect the city water sup
ply main from the wells will be nearly
as large an undertaking as the dam
built in the river at Center street.
plans for the dam and retaining walls
arc now we'll under way in the office
Of city Engineer w. H. Steiner. The
| cost has not yet been estimated, bur
Councilman John 4. Bell believes thas
it will be $4,000.
AS prepared the plan provides not
only for dam across the channel put
for retaining walls below the dam.
The dam, as proposed in the plans, viii
be 1874 feet long with retaining walls
sixty feet long on both sides OF the
channel.
Will Be Permanent Dam.
The plans may be revised before be-
ing accepted by the council, but 1t Is
probable that the job on which the
city will ask for bids will be very SINH
lar. if not identical, to the plans now
being made.
The dam. which will reach from
bank to bank of the channel, will De
attached at either end on the down
stream side to retaining walls that VIII
run to the concrete bridge across the
channel at Center street. These walls
are to be built to prevent flood wafer
from cutting away the banks OF the
channel, and it is possible that the
council will consider building an apron,
Or floor, On the bottom Of the channel
below the dam to the bridge.
Footing of PiIing.
Dam and retaining walls will be-
built on footing of piling, driven as
close together as they can be easily
sunk. From bottom to crest the dam
will be sixteen feet high. and the crest
| will bee about two and one-half rect
higher than the top Of the supply main
that spans the channel about 100 feet
above the proposed site for the dam
The dam at its base will be little
less than ten feet thick, and the down
stream face will have batter of one
half foot to one foot. The base OF the
dam will be on average about four feet
below the. bottom Of the channel. The
dam and retaining walls will be rein
forced with steel. and are expected 70
be of sufficiently heavy construction to
stand up under any height Of. flood
water.
Objects Aimed At.
Three objects are aimed at by the
building of this dam. The water Level
that will be created at an elevation
equal to the crest of the dam will be
severAl feet above the ordinary water
I levels In the river at the mouth OF
Asher creek. This will result in turn
ing back into the old channel OF the
river below the mouth Of Asher creek
much Of the water that has been goins
| thru the channel that is to be damned
It. is expected, that this changing o.
| the flow Of water back into the old
| river bed will wash out that channel
and force much more water over the
| old dam.
1t is expected that silt will be de-
posted above the, dam which will make
the channel much more shallow at that
point and furnish additional protec-
ton for the pipe. The creating Of a
higher water level in this channel
which is near the city water field, will
| maintain higher level Of water in the
water field in which are the shallow
wells and thus insyre a larger supply
This last object, however, now Is not
so important if it proves that the city
| is going to be able to secure an abund-
ant water supply from deep wells.
1 & srt5. Il h.