Delaware gazette and state journal., 1896-01-30
From our washington Correspondent.

From our Washington Correspondent.
Washington, Jan. 23 The report of
the survey of Wilmington harbor and
the Christiana river, made by Major
William +. Smith in compliance with
the provisions of the River and Harbor
act OF August 18th, 1894, has been
printed and is now before the House
committee on rivers and harbors. The
survey was commenced in September,
1894, was discontinued by reason Of the
incemencyo of the winter for about two
months, and was completed in April,
1895. 1t comprised a photographic
survey OF about 20 miles; also tidal,
fresh water, and current and sediment
observations Major Smith proposed,
in addition to dredging, rock removal,
and jetty extension, the construction
of flushing basin at the mouth of the
river, the entire work estimated to cost
81, 269, 494.
Major Smiths proposition TO con
struct flushing basin was not ap-
proved by the Board of Engineers, or
by Brigadier- General W. p. Craighill,
chief of engineers. The board made
careful inspection of the Christiana
river by means of tug boat, and after
a careful consideration Of the subject,
reached the conclusion that in view of
the great cost of the proposed flushing
tidal basin at the mouth of the Chris
tiana river, and the uncertainty of the
reasults to be anticipated from its en-
ployment and the evident difficulties of
construction, that the desired depth at
the mouth of the river could he more
certainly and economically obtained
and maintained, either by dredging
alone, or by dredging combined with
a ietty on the south of the mouth of
the river. The following is an extract
from Major Smiths report of the
survey:
The observations began at time
when the fresh water tributaries were
probably at their lowest ordinary stage.
and continued so as to get the effect
of the autumn rains, and also some
what the effect of the melting SHOWS.
They may be assumed, therefore, as
being sufficiently accurate for the need
full purpose of the survey. The result
shown by these observations gives for
the Christiana and its tributaries a
total fresh water inflow of 6l7 cubic
feet per second. An examination Of
the rainfall and the area of the water
shed gives larger infow-759 cubic
feet. This, at velocity at bottom at
low water of 0. 60 per second, is enough
to carry with it to the current of the
Delaware all sedimentary matter in
motion coming into the Christiana eX.
cept in time Of freshets or the surface
wash Of Wilmington in heavy showers
?, The rise and fall Of the tides in
the Christiana. The tidal wave which
hrt al :
Delaware river has its velocity reduced
one-half for the high water and ono
third for the low water. This diminu.
tion Of velocity is partly due to di.
minished depth on the cross section
and partly to obstructions, such as
bridges and bulkheads built without
the authority Of the United States
government and without any reference
to the preservation of a proper path fol
, the tidal inflow and outflow.
The observations taken show that fo,
distance OF five miles from the mouth
OF the Christiana the ordinary rise ant
fall is about q feet, increased or di
minished at times by high winds blow
ing up or down the river From tn,
Five Mile Point to Christiana, II
miles higher, the tides diminish 10 /
rise and fall of 3.6, while liz mile
above, at Smalley's dam, tho rise il
but one foot
In the reaches above Newport ther
are gravel shoals which interfere Will
the free circulation Of the tides.
The rnean inflow at the mouth durini
one food is lag. pa 369 cubic feet.
The moan discharge during one ehI
is 10, 2S1, 2O9 cubic feet, or prepon
derance In the ebb, owing to the in
coming fresh water, Of nearly 80, 600, 90
cubic feet
The moan velocity at the mouth afte
ebb is o. % foot per second, or the com
puted velocity at the bottom is abou
U, 20 foot per second, giving a scourin
effect due to the inflow of the Chris
tiana and its tributaries
Ihe plan recommended for channC
u feet in depth The incoming and out
flowing tides have their natural effeC
diminished by great variations in tn
width Of the cross sections and in til
obstrnctions cause by the bridges
10 get regular action by the It'd;
prism, | would recommend higt
water width at the mouth Of 800 feet
gradually narruwingH 10 300 at th
Third street bridge; that the cham,
should be confined between those imit
by bulkheads or dykes, t. be erecte
by the riparian owners who would ut
tam their compensation in the increas
OF solid land between the bulkheat
and present high waicr line. The widt
OF the channel at bottom should be ;,
feet to the mouth of the brand win,
the surface width following the huI
head line, gradually diminishing fro
5OO feet at the mouth Of the 300 fe
near Third street bridge, which widt
OF 800 feet for the high water liz
should be continued with the bulkhe;
10 the Market street bridge. The Wild
at bottom of this section to be 200 fee
from there to the lower end Of Il
centre pier OF the bridge Of the Pen
syNania railroad cutoff the cham
shoulu be 200 feet at the bottom, m
nave the present width at surface. III
width above the Market street brid,
gradually increasing for the high-wat
line To 1VO feet would, with the Cunsta
inflow Of water from tho Christian
watershed, make a kind Of tidal has
OF that portion of the trough Of I
river, and aid in increasing the SEQ
on the ehh. The depth Of the chanr
from the mouth TO the upper line
the pulp works should be- u feet
mean low water.
From that line to tho draw III
above mentioned the depth should !
nlnsh to 10 feet al mean low wat,
giving a SLOPE of 10 feet in 40
length, From this per 20 Newpor
would recommend that all shoals hi
ing less than feet in dcuth be
moved. They are generally hard b.
tom o. gravel or rcd clay.
J have laid out nn the chart at
mouth Of the Christiana a tidal ba,
containing los acres which Wiu coli
during an ordinary food tlIr, hog