The Donaldsonville chief. [volume] (Donaldsonville, La.) 1871-current, 1907-01-26
THE LAFouRcHE LOCK.
Continued from First Page.

rounded the permission given TO open
the Company canal and Harang's
canal into the bayou by provisions
which will exclude salt water from
Bayou Lafourche should they become
a menace IN that direction.
tAllofthese canals will give large
supply of fresh water to Bayou La
fourche during periods ofrainfall, but
during periods of drouth they cannot
be depended upon for a supply of fresh
water, as the basins with which they
connect fall, at those times as low as
the level of the Gulf.
" In orderto supplement these canals
your board established plant of five
18-inch siphons across the dixie at
Donaldsonville. These siphons run
naturally when the river is high, and
are assisted by floating pumping
plant, situated at Donaldsonville, dur
ing the period of low water. These ST.
phons have capacity we'll over So,
900, 900 gallons per twenty four hours
during high water, and the pumping
plant was designed so as to give them
a $4,000, 600 gallon capacity at low
water season. Upon test, the pumping
plant fell somewhat short of this ca
pacity, delivering 47,439, 900 gallons
of water over the dixie instead of the
required $4,000, 600 gallons.
Ion general principles, although
water coming from the Mississippi
river is very good and fresh in char
acter, yet it carries with it a consider
able amount of sediment, which will
be deposited short distance from the
dixie, thereby filling up to certain
extent the bed of the bayou and un-
doing your efforts to dredge out a
six-foot channel. It is estimated that
50,000,0 900 gallons of water at high
water season will carry 200 cubic yards
of sediment, which will be deposited
in the bayou and which will have to be
removed by dredge.
During the winter season of 1904 5,
an unprecedented condition of dronth
prevailed throughout the Bayou La
fourche region. The result was that
the Lake Boeuf canal did not supply
any quantity of fresh water worth
mentioning. Your honorable body
decided to build a needle dam just
above Harang's canal, so as to pre-
vent the inflow of salt water into the
bayou. The work, however, was be-
gun so late that it was not completed
until the grinding season had begun,
and a large quantity of salt water
found its way up the bayou-from the
sea before the dam was completed.
The erection of the pumping plant also
was begun late; the pumps did not be-
gin oper ating until some time after
grinding had commenced, and for two
or three months after they began
operating the reports show that they
never operated more than four
siphons, and sometimes only two
siphons. Under the circumstances, a
considerable amount of salt water was
to be found in Bayou Lafourche, ex-
tending at times as far up as the Bush
Grove sugar refinery.
est would be desirable to make
provisions early in the season against
repetition of such conditions. The
pumping plant should be put in
thoroughly efficient condition early in
the season, and should be run by COM
petent men, so that it might operate
at its maximum capacity throughout
the grinding season. The needle lam
should be repaired and put in condi-
ton early in the season, so as to be
efficient if it is needed. The interest
contr olling the Company canal and
Harang's canal should be called upon
to provide such gates or needle dams
as might be necessary to close their
respective canals az once, should they
become a source of salt water during
the grinding season, and in addition
to this an additional source of fresh
water should be secured by opening
canal connecting Lake Verret with
Bayou Lafourche.
81 can see no reason to depart from
the recommend ations made therein at
that time, except possibly so somewh at
amplify the plan. The board of state
engineers holds itself in readiness to
submit to you further studies of the
subject should you desire it.
TN this connection | desire to re-
fute a popular misconception regard
ing the construction of the proposed
locks at Donaldsonville. A large num-
Der of persons are under the impress
sion that the construction of locks
will insure fresh water to Bayou
+ afc
be that the locks will remain open
until such time as there is danger of
overflow in Bayou Lafourche, and
that they will then be closed. This
is an absolutely wrong impression.
No.tlocks are, nor can be, success
fully Opera ted 10 this manner in
silt bearing stream. The locks would
be kept closed at all times, and only
opened, one set of gates at a time,
when boats or water craft. went
through them.
sit is obvious that if the locks
were allowed to remain open with a
current flowing through them, espe-
cia1ly current carrying silt, it prob
ably would be found impossible to
close the gates when it became nee
essary to do so, the efficiency of the
locks being thereby destroyed and
resulting in the overflow of the whole
country. Again, lock gates and their
operating mechanism could not pos
sibly stand the strain which would
come against them if they were closed
against an inrushing current, and
they would in all probability be
crushed and shattered in the attempt
to close them under these conditions.
The locks would therehv he destrnund