The daily union. [volume] (Washington [D.C.]) 1845-1857, 1857-02-12
BRIDGE ACROSS rHE POTOMAC.

the Potomac river at this point by the great ice food Of
Sunday last II may be mentioned as singular conci
dence that almost simultaneous with the news of this dis
have the elaborate and abyprepared report and
surveys made in obedience to joint resolution passed at
the last session of Congress- respecting the construction Of
new and substantial bridge across the Potomac We
learn, from communication addressed the It'll inst
by Secretary McCleand to Hon. NJ Mason President Of
the Senate pro tenn that the execution of this law was in
trusted to Alfred L. Rives esq With what ability and
fidelity he has executed his task may be Inferred after
perusal of the following report which now in the hands
of the Senate Committee the District of Columbia
wAsHseros, Feb. s. 1857
Sir have the honor to submit to you the following
report the result of my labors In carrying the reo
luton of Congress calling for plans and estimates for per-
manent bridges the Potomac For the precise ma
ure and condition OF the duty assigned beg leave to
refer the communication addressed to from the De-
partment Of the Interior under the date of the 18th of
September last which is herewith annexed, marked A."
The very limited time allowed will hope excuse any
omission of details that might otherwise have been prop
erly presented.
II is evident that plans for permanent bridge at Wash
ngton cannot be properly matured without due regard
to the interests Of navigation should the equally vital
and important question Of railway communication be
overlooked thorough examination of the river and ad-
jacent country was therefore, deemed Indispensable
complete hydrogf aphc survey, isee accompanying map1
extending distance Of six mesfrom the island rocks
called 1hrte nall mile Georget0wnO
to Geesborough Point Zone mile below the arsenal)-es
abshes concusvey that improvement in the actual
state of the river is mpeatyey demanded The depth Of
the Potomac at the Three Sisters is eighty feet and
thence quarter of mile below Easbys wharf varies
from twenty to thrtythree feet Below that point the
current spreads itself immense surface gradually
losing its energy until the channel presents depth of only
feet and eight feet at extraordinary low tides
As the tide rises only three feet this depth wholly made
quae for the purposes OF navigation the
way of the Long Bridge contracts the current that we
again find depth OF thirty-tw0 feet. Below the Long
Bridge there exist two channels-the Georgetown or V
gina, and the Washington City channel The former is
by far the considerable until the tides of the Eastern
branch their beneficial influence the latter After
the junction Of the two channels the water attans depth
of fifty-four feet
Ii VIII be seen from this description that there are fats
separating the Washington and Georgetown channels and
extending far the Eastern branch 1t has very
common to assume that these fats owe their origin tho
causeway constructed to facilitate the erection Of Long
Bridge. This however, seems to me singular confusion
and effect The causeway resulted from the fats
channel through their midst which, with without the
Long Bridge causeway, must eventually have disappeared
as consequence OF the permanent connexon of Mason
Analosan island with the Virginia shore Examination
Of old charts well reflection upon the necessary OPP
eraons Of nature convince that these fats date from
period long antecedent to the erection of the causeway
That they have increased rapidly during the past
fifty years is bat natural when consider what de-
posts result from the eshet of the Potomac
rendered doubly turbd from washing the shores Of
highly cultivated region 1t must be evident that ploughed
hilsides furnish aluvia deposit than unbroken for
grassy slopes By the operation of these and SINH
lar causes many ports formerly deep and accessible
scarcely exist Of which Bladensburg in immediate vi
entity and others rivers of the Atlantic seaboad
are familiar examples.
In many this state of things admits of no remedy
without great and continued expenditures The Of the
Potomac at Washington ia happily different Here the
volume of water amply sufficient when properly directed
by one initial expenditure to insure good and lasting
gaton So long however, its energies wasted by
diffusion large surface expect changeabe
and insufficient channel have therefore prepared the
following plan requiring comparatively small expenditures
and which deem certain in its operation, snd leading
most enduring and beneficial results 1t 10 but the compile
ton of work commenced by nature 1t consists In open.
ing clear waterway of ITO feet along the Washington
shore by removing portion of the existing causeway and
replacing II temporarily by wooden structure piles
lowering the dam connecting Masons island with the Vr
gina shore as 10 bring level with extraordinary
high tides and terminating its upper surface by inclined
plane OF masonry dredging short channel
portion Of the fats building breakwater from the south
point of Masons island to defect the of the
river into the channel; and finally retaining l66
of the flats at the mouth of the Tber thus gvngs
continuous and deep channel along the Washington shore
The Tber more properly the City canal should be
uued to the shore line and guardlocs be placed OF
its into the river The outlines Of this plan are
exhibited on the accompanying map.
The advantages resulting from these arrangements may
be summed up as follows: wa
LIST. The permanent Improvement of navigation say
permanent because the river will be confined in sufficient
ly narrow channel for three-qdarters Of q mile below
Easbys wharf by the proposed breakwae which leaves
in direction normal to the Long Bridge finally passing
directly through the opening reserved for IT, and becoming
tangent to bold curved shore Of wonderfully regular
line well known that curves form stable
and deep channels The current we have to deal with
below the Long Bridge be Of such violence
form exception. remarkable confederation Of this
fact may be found by referring map Of the Potomac
published as far back 1892 The old spash channel
formerly of considerable magnitude showed disposition
to defect although striking somewhat obliquey against
the Washington shore On the contrary, it followed its
curved outline with willing mathematical precision An
examination of the accompanying map must convince any
unpreudced mind that the proposed channel cannot
by any possibility njure and will in all probability i'm
prove tie mouth of the Eastern branch which the Uni
ted States have very important interests connected with
the navy Lower than this it is obvious the regime Of
the river cannot be affected by the proposed changes
may be objected that there perhaps exists nau
objection of this nature thought il well to ascertain
positively the character Of the auval deposit For this
purpose caused to be constructed simple wooden rod,
poined with iron Two forced 1t down depth Of
twenty feet below low tide in no less than fifteen
spots taken over the surface proposed to be appropriated
TO the new channel This test settles completely and
clusivey the question Of feasibility preliminary chan
mel hundred feet wide twelve feet deep at mean low
tide connecting the Washington channel with the deep
water of Easby's wharf, could be easily and promptly
dredged The current would do the rest II
hdently believed that by constructing the breakwater in
sections the amount to be dredged be greatly dmn-
shed For this purpose is proposed make the break
water IN the FIRST instance only to the Virginia channel
there leaving passageway of two hundred feet
for navigation while prosecuting the reanng portion Of
the work on the other side The present Virginia channel
would be thus temporarily improved where II is de-
ective and yet large proportion of the descending
rent would be DETECTED to the Washington shore and
ert it's force in completing the work commenced by the
dredging machine The moment the new channel shall
nvnc ant l. - II r.. a.