The Cairo bulletin., 1910-03-28

A recent NUMBER 81 the EHSaHsti'
ling Contractor published in Chicago
contains an interesting description ot
the plant OF the Cairo Sand & Gravel
iCo., with numerous Illustrations
Ishowing the arrangement OF the
nlaflt, the manner OF its operation and
the conditions surrounding 1t. The
lsiory is from the pen OF Jean Nj Al
lien, who was superintendent of the
company and under whose able man.
agement the plant did splendid work.
Mr.. Allen is now in charge OF exten-
interpretations on the Erie canal. The
story is as follows
I A notable job Of hydraulic filling i
now in progress at Cairo, Ill. This
fcity has a large acreage OF low
areas resulting from the building of
'ffnYees and the establishment Of the
city grade frcm Q it. to 2 IT. above
,taa4 eEiginal ground, and this low
/ ground has been d handicap to the
| physical development of the city In
the early day large amount OF the
| low ground was filled in BY hauling
In material by teams. The fact. how
Iever that there was In the Mississippi
lriyer iwst back of the city and within
Ia mile OF the lowe / areas large
lsand bar sngge ted tie praetieability
| of hydraulic filling and In 1906 a local
company with capital stock OF
800 ,0G0, was organized to take UP this
work and contracts amounting to ap-
nrDximatalv 500 600 cu yds. were
taken OF this amount about 2Ta,0t
cu. yds. were for the filling OF the ter
minals OF the Cairo & Thebes r. r.
and about 100000 Gu yds. for filling
the low streets of the city. This com
pany was originally the Cairo Con-
tracing & Dredging Co., but was
later reorganized as the Cairo Sand
4 Gravel Co, which company Is now
carrying on the work.
Regarded ais a hydraulic filling pro-
position some rather unusual and diff
ficult problems pre- ented themselves
The extreme di tanee to which the
material must be pumped was some
thing over G,5o0 IT. and the greatest
elevation to be overcome at extreme
low water was about rs 3t. Extreme
low water Is about 1T. referred tol
zero on the government gauge at this
Point and the city grade Is 43 fl. re-
ferred to the same gauge. AIS ii wall
intended TO rise f2+in. pine and a. al
velocity OF water of at least 10 ft i
rer second must be maintained toi
keep the heavy sand and gravel in
suspension, total friction and static
head Of about 500 IT. had to be ever
come.
There eemed very few data avail
able on plant of this kind Some of
the builders OF tandard dredging
pumps declared that the proposed
heads were excessive and declined to |
submit bids on the equipment. All
somewhat similar plant found WORK
ing in Kan as City, wa carefully |
studied and much valuable infofma-
tion was gained therefrom.
The following was the plant event !
ually decided upon and installed. A /
floating dredge was Installer in the
Mississippi river adjacent to the and /
bar. II was connected to the bank by |
a pile tre tie extending into the river
a distance OF 100 1T. and by a rigid |
pontoon line 1G0 it. long connecting
the boat with the treste. Articula. |
tions at the connection of the trestle |
with the pontoons and of the pom
toons with the bow Of the boat en-.
abled the suction pipe, located at the
stern Of the boat, to pump sand from
any point In the interior of a semi. |
circle whose radius l. $50 TT.
On the boat was installed a 12-fn. !
centrifugal dredging pump of stan
dard make with 92-in runner THIS
pump was beltel to a 20x24in. slide
valve engine. Three Mississippi
River boilers, each "A in. in diane
ter and p It. long, supply steam at
pressure of 140 lbs To save time
necessary to construct hull for the
dredge river tow boat 141 it long
26 It. beam and Az it. deep was Sc I
cured and the dredging machinery
rlaced upon it The boats origint' I
bailer, feed pump. and capstan We're
utilized in the dredging equipment
The suction pipe passes over the
stern OF the boat and ls raised and
lowered BY q small hosting engine.
In high water periods this suction
pine i about so it. long. /
A shore pumping plant or booster !,
plant was located just inside the
levee at a distance Of about 1900 IT..
from the boat. The pump and engine
N Y