New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1874-05-22
he Edttor of The Tribune.
OF ISEFFICIENCY,

ORDINARY PRECAUTI0SS-A MELANCHOLY slohi
OF INEFFICIENCY.
TO the Edttor of The Tribune.
SIR: But little remains of the reservoir dam
Of the Mill River and Williamsburg Reservoir Company
There is however, enough to clearly show that grave
errors were committed in its construction No sudden
acereon waters took place burst this DAM as was
the OF the other dams Of local mill ponds
further down the stream OF Mil River-but 1t burst
and evidently has been upon the point OF Durst
ing because 1t was totally Inadequate 10 serve
its intended purpose In engineering terms, the struc
had cupably insufficient coeicents OF safety ana
stability At this writing have not had time to go
into details OF calculation 10 enable me 10 state pre-
csely these coefcents were in this particular
case indeed when the facts fully stated Will be
seen that rihe more or less one way or the other
would made material difference in the result.
say that IL the plans and specifications OF this
DAM built had been submitted to any com
petent engineer that he would have ioleoiu the result
which has just happened.
have tried to get the existing original specifications
OF this dam TO enable to II the work was done in
accordance with then-but was Informed by gentle
man who just and read them, that he did not
believe that they would be made public or that Ishoud
be allowed TO examine them.
can therefore only speak OF what actually saw Cd
the spot ;and from tue observations there made slal
draw the conclusions which follow.
The site OF the reservoir dam is three miles above the
gorge bounded by steep hills either side The loca
ton is good one and there is every natural advantage
that could be wished by the engineer To enable hlm 10
construct permanent and thoroughly safe DAM
Taking position a hundred yards below the line of
the dam and looking up stream the observer sees oe-
fore him the gap opening through which the pent-up
waters Crushed with such terribly destructive force
The remaining walls show that the devastating stream
let loose on this occasion had width Of about l75 feet
and an average depth of about 35 feet.
The section of this stream was bounded at the
side by two vertical walls about 80 feet HIGH and at the
bottom by a remaining wall OF 100 feet in length THIS
bottom wall is about eight feet high at the deepest
point Of the ravne and extends nearly level on It's top
surface till IL meets the clipping natural ground This
latter Was the foundation upon which the entire sruc
ture was based and constructed. The soil and upper
surface for depth OF about 30 inches was seoved' ana
the hard remaining bottom, consisting OF small stones
embedded tough earth thus exposed, was the natural
foundation upon which the masonry OF the Dam Rested
This is apparent by inspection Of the ruins sandng on
the east side.
The aforementioned bottom wall shows this portion
OF the masonry to be five feet thick Ii proper here
to note that small portion is made ABOUT TWO iee'
thicker by the addition OF patch stuck against he
lower side place where the main part was not up 10
the exceedingly low standard shown by the ad)aceht
parts.
The reason why this remaining 100 feet Of the bottom
part OF the wall not carried away ls that IL was
sustained by a certain cross-wa about eight feet hgb
which made an effective abutment for It, The ONCE OF
this crosswa was to support an iron pipe 10 hehes III
diameter and about 100 feet in length, through whch
the water from the reservoir was leo through tue paSe
OF the dam.
Between the east wall and the easterly end OF the
bottom wall distance OF 90 feet on the natural slope
there is not the slightest indication that the place was
ever occupied by an artificial structure Ascending the
hillside to the level of the top OF the dam, the general
appearance Of the ruins Is as nearly as possible the same
ma II the work was part OF heavy railway embank-
ment with vertical wall two feet thick at the top run
ping through Its length from top to bottom
1t strikes an engineer as remarkable 10 SEQ that
tins wall fully feet in hight should nave oeeh oui''
IA IL WAS IN straight line from one hillside TO the
other when by constructing II on curve Win the
convex side up stream, the same wall "oud nave oeeh
increased In its resisting over anu emcehey'
For with the form suggested this wall wouid nave been
an arch laid upon its side, with everlasting nils Tor
abuments OF course. such an arch shouid DC puiit
with ntegrty and honesty every foot OF It's contents,
which cannot be said to be the case with the miserable
straight line cobble mural abortion under dscusson
IL totally unworthy Of the dignity OF Oehs called good
| rubple masonry.
II was not laid regular In It's courses, nor with any
thing that an engineer could pass as good mortar.
mean % say that where the fracture likely
and did occur in the place Of good mortar OF hydraulic
cement found sand which could readily remove with
nv fingers. aud OF which have retained specimen.
II any theory In respect TO the duty and functions OF
this wall was held by the ncapables who designed ana
executed it, far have been unable TO ascertain what
| that theory was.
Iii most likely that the wall relied upon as the
prpcipal obstacle to stop filtration through the embank'
men forming the body OF the DAM which OF Itself was
| lily adapted to this purpose.
| "Rprap" resting upon stratum OF earth covering
layer Of brush presents face OF soping stonework on
that part OF the embsnkment the upstream eide at
the west end OF the dam Nothing, however, appears
which would be generally imperyous TO water I'll the
YsgI.sA w. u gsasssa apd grave rsa'Qps w !p!lA