The daily dispatch. [volume] (Richmond [Va.]) 1850-1884, 1882-03-16

ktvef-lmproycment Committce-The Wa.
ter.Way from Richmond 10 tho Sea; Its
Present and its Future.
Colonel Whitcomb, in his annual report
TO the James-River improvement Commit
tee (of which l.. ID. Crenshaw, Jr., Is
chairman), gives great deal OF valuable
information concerning the operations
having for their object the improvement Of
the james from Richmond towards the sea.
He says the "Unitcd States engineers have
spent considerable part Of the year in
making an examination OF the riyer-bed
from Richmond to the lowest shoal,
having less than 2j feet depth Of water
at full tide, with view to estimating
the cost OF making the channel every
where Of that depth. This survey, under
the direction OF Captain Thomas Turtle.
OF the Corps Of Engineers, who has been
in charge OF the improvement since Au-
gust, under Colonel w. u. Cralghill, has
been made in a very thorough manner by
Mr.. c. l.. i. Burgwyn, assisted by Captain
Thomas Cunningham and others, Including
the crew OF the tug W. T.. Craighill.'
Further on Colonel Wllitcomb gives the
following
GENERAL CONCLUSIONS:
As an evidence OF the improvement
which has already taken place, the ships OF
the Old Dominion Steamship Company
now leave at a regular fixed hour, instead
Of as formerly. waiting for suitable
height OF tide. A few years since, TO cna-
bic them to leave at high tide part Of their
cargoes were delivered to them below
Warwick bar, and for six months IN 1871
these ships dId not come to the city at all
they took their cargoes sixteen miles be-
low, In Trent's Reach, where a bar with
only 10 feet at high tide existed. the Dutch
Gap cutoff not being navigable. At this
time Richmond bar had but l0i feet. In
1873 the engineer, Major w. q. Turpin,
reported such improvement that vessels
drawing I2t feet could reach the city at
high tide. During the past year
VESSELS DRAWING 1Gt FEET
have left the Chesapeake and Ohio Railway
wharves, and under good pilotage could
have left the wharyes at Rockets Rich
mond bar has had 1s3 feet in channel.
Trent's Reach shoal, now avoided by the
cutoff at Dutch Gap, has not been dredged
since 1871, and has even less water over it
than there was ut that time.
In several OF the annual reports since
that of 1874 IL has been stated that the
cr.ss section OF the river, i'm reaches OF
say 5000 feet, showed a very con-
slant area for each reach, increasing
with great regularity down the river, at
least as far rs Dutch Gap, which was a. far
rs surveys permitting their computation
were available. These cross sections were
taken about every 800 ieet, the surface
width varying considerably in each reach.
Ii was found that the varying surface
width was accompanied by
A REMARKABLY UNIFORM AREA:
the average depth varying in an inverse
ratio to the width, so that the wide places
in the river were shallow and the narrow
places deep. While it was suspected that
these uniformly increasing cross sections
might continue much lower down the river
than Dutch Gap, there was no sufficient
data to prove il until recently. Mr.. Bur-
gwyn, who has been following up this sub
ject, and has been making an examination
Of the shoals i'm the lower reaches. informs
me that he finds this to be the law as low
down rs Swan Point, 65 miles below Rich.
mond. Here the river varies greatly III
width-yiz., from $1,000 to 1000 feet-yet
the several areas vary but II per cent. The
details will appear more fully in his report
10 Colonel Craighill. This law OF steadily
increasing areas. II finally established, as
confidently expect, has most important
bearing on the
STABILITY OF THE IMPROVEMENT
now being made. II shows that the pre-
sent volume OF the river. whether caused
by fresh water from above the falls or by
the tidal waves from the ocean, demands ;
certain cross section 10 carry ii. and thl'
may be broad and shallow or narrow anC
deep; and that il the broad places, whlcl
are always shallow, are contracted in wldtl
| that the increased current will deepen th'
channels il the bed j. in materials whicl
can be- secured. This has been the effec
above Warwick bar, where the river hai
been reduced in width by dykes and wing
dams.
/ The channel has been decponed, an(
/ freshets, which formerly renewed the barr
which had been dredged, now aid in thei
removal. There are
no sInFTING EARS ~ JAMES RIVER.
| Ali appear 90 he now just rs the earlics
surveys found them. Being due IL cluse
which are apparent, they can be perma
nently removed by removing the cause
/ Generally this cause il excessive width o
surface. At IIarrison's bar and Coos
Hill flats, and possibly at some othe
points, 4 hard-clay or cemented material i
found in limited amounts, whichihas hin
dered the current in deepening the chan
mel. and may in the remote past have caused
the river to widen It's surface. In sucl
cases dredging alone may be found suili
cient to open channel which will 40
AGAIN he silted up. The indications ut Iiar
rison's bar at least favor this, and 1t Is pos
sibIy the case at Goose Hill, but above Cit.
Point it seems probable that the width
the river must be regulated by dykes ant
dams, and these will not b. eXpehsive-no
so much so, ! should think, rs resort Z
dredging every few years. Below Cit
Point. where the dykes would be muc
longer and in deeper water, it will proba
blv be found cheaper to resort to occa
sional dredging.
/ have every confidence that the rive
can be permanently
IMPROVED TO ANY DESIRED DEPTH.
II is simply n question OF what tcidh wi
he allowed between the dykes. At Drewry'
Rhid. seven miles below the city, with
natural width OF 600 feet, there is cor
slant depth OF 30 feet. There is no reaso
apparent to me why that depth could no
be carried to the sea, with constaDtiy-ir
creasing width. No such scheme
now under consideration. / mention
only TO show the possibilities. The estuar
| OF ine clyde was formerly bare at low It'd
, for about eight miles below Glasgow, an
, only the smallest class Of vessels came
The city at high tide. Now vessels OF 2;
: feet draught steam up to the city. I'll
width OF the Clyde appears to be not owe
200 feet at Glasgow, and docks are nece'
, sary to net only hold the ships. but to el
80 10, vi