Itwyn's grand ^aiiilile II
how to open an inlet
Currituck Sound, ihowmg the Wright Memorial Bridge linking the moinlond with the Bonk».—
(Photo by Aycock Brown.)
The reflux tides occasioned by the
hack waters of the south easterly winds
opposed by the flow from Albemarle
Sound, have maintained its depth, as
is evident from the channel being on
the south side. It has not improved,
for the obvious reason that the bulk¬
heads and shoals formed within the
inlet, before the opening of the
marshes, oppose more resistance to
the passage of the water than its
tendancy to run in that direction, even
with a greater descent, is capable of
overcoming. "For the natural tendency
of water is. to make its way in what¬
ever direction it finds the greatest de¬
clivity; and if this happens to be in
the shortest direction, it has no natural
tendency to gain a longer course, as
that would lessen the declivity. If.
therefore, water is found pursuing a
direction which is not the shortest, wc
may conclude, (and, on examination,
wc will always find,) that the longer
course is owing to the intervention of
some obstacle, so placed that the
waters cannot have, at that particular
point, a more speedy descent in a di¬
rection different from that which would
form the shortest line of the whole
descent; and. from causes of this kind,
a stream may have a course meander¬
ing in every possible direction, as wc
frequently observe in nature."
Having considered the causes of the
closing of the inlet, and the objections
to its practicability. I will now take
into consideration the plan and effect
of the works for rc-opcning it.
The universal plan of improving
harbours is. to contract their outlets by
the erection of piers, sometimes pro¬
jecting far into the sea, to turn the silt
and shingle brought coastwise across
the inlet; to pen up the tide water in
pools or basins, and let it out at the
proper times — in some instances,
through pipes or tunnels, to act as a
scour in conjunction with the ebb tide;
or by damming and canalling, obtain
and turn through the harbour an ad¬
ditional quantity of water from the
land, with the view of obtaining an
artificial scour, in imitation of the ef¬
fects of a fresh water river.
These plans arc all derived from
nature. The natural means by which
an inlet is kept open is, the discharge
of fresh water through it; which, op¬
posing the influx tide, and adding to
the power of the ebb. will always main¬
tain a certain channel in proportion to
the quantity of land water to be dis¬
charged. The tendency of nature is to
contract the channel to such a size, that
the natural power of the stream can
just maintain it.
From these plain and obvious prin¬
ciples. the plans mentioned have been
derived; they guided even the first at¬
tempts at the improvements of har¬
bours; and, up to the present time, they
govern, without a single exception
worthy of notice, in the improvement
of all the harbours on the coast of Hng-
T his is the second in a scries of di¬
gests of Major Walter Gwyn's report
in 1 840 on the feasibility of closing
both Roanoke and Croatan sounds,
tints diverting the current of Albe¬
marle Sound, and reopening old Nags
Head lor Roanoke) Inlet.
land and France. Wc but follow nature,
therefore, and all past experience, in
pursuing the plan I propose for re¬
opening the Inlet at Nag’s Head, to
wit, to cut off all communication be¬
tween Albemarle and Pamlico Sounds
by dams, and thus turn all the waters
emptying into Albemarle Sound
through Roanoke Inlet — the effect
of which, I have no doubt, will be to
preserve a channel at least fifteen
feet deep.
Under circumstances not more
favorable as to situation, winds or
tides, and with not one fourth the
volume of water. New Inlet, at the
mouth of Cape Fear, maintains a depth
of 13 feet. Over the bar at Ocracockc
there is I ft feet, and at New Inlet,
the northern outlet of the waters of
Pamlico and Albemarle Sounds, there
is a depth of 12 feet. The obstructions
being on the inside over the swashes,
wc may therefore confidently de¬
pend upon at least 15 feet on the bar
at Roanoke Inlet, and, as will presently
appear, the situation is such that there
will be no inner formations or ob¬
structions.
The north cast wind, aided by a
io
THE STATE. November 3. 1956
