The Virginia enterprise. [volume] (Virginia, St. Louis County, Minn.) 1893-19??, 1915-06-04
Duluth Engineer Submits State
ment to City Council Cover
ing Construction.
COUNCIL ACTS ON 1T
AT NEXT MEETING
Found Sewer Was Constructed
In Workmanike Manner, But
Contract Was: Ambiguous.

foot sewer, winch Will be MADE at the |
next meeting, of the city council. AS
there is general interest in Mr.. Will
sons report, the full text Of it is given
below.
"In. accordance with the instructions
of your Committee, I have inspected
the condition of your six foot storm
sewer, measured and recalculated, as
far as possible, the unit quantities and
have reviewed the contracts and spe-
cifications relating. to the work.
I'm general l would say that the
appearance of the sewer indicates the
work had been carefully and we'll
done. There are some defects, such
as a few loose blocks, in the invert
of the sewer, evidently water had been
allowed to flow through the sewer be-
fore the mortar had sufficiently har-
dened. There are few places where
evidently there was carelessness in
following the grade but as these de-
viations do not exceed four inches, the
effect upon the operation Of the six
foot sewer will be insignificant.
There are also a number of longi-
tudinal cracks, the greater number ap-
pearing below the springing line and
along the crown of the arch. The
most serious of these cracks are near
the Canadian Northern tracks for a
length of about twelve feet, just how
serious they may be time alone can
determine, in view of which they
should be closely watched.
"Segmental blocks were first placed
on the market in 1911 so that there
! can be at present no we'll established
practice in regard to their construc-
ton. I. think the general practice is
to place them directly upon firmly
tamped base without. the use of any
mortar cushion. l think it unreason-
able to say that a one inch mortar
cushion would be Of no value, and
equally unreasonable to attach any
considerable importance to this cush-
| ion in the way of additional strength
impaired to the sewer.
"The concrete base provided for in
case Of soft or uncertain foundation
would be sufficiently massive to fur
nish very staple foundation under
very unfavorable conditions. The
one inch mortar cushion I have esti-
mated as worth twenty-five cents per
lineal foot of sewer, while the con-
crete base would cost about 200 per
lineal foot. l am advised that the
foundation was firm for the entire
length of the sewer in which case the
concrete base was not called for.
1.-THE measurements upon which the
j estimates were prepared seem to have
been. carefully made; while / differ
somewhat as to the quantity of earth
excavation, l would suggest that
>so ln%A h&v 1yo,,ve oi%1y min.
eer be accepted as correct, as these
measurements could be more advan-
tageously taken at the time of con-
struction. Some Of the methods
adopted in making the measurements
and in calculating the quantities are
not strictly according. to the contract
and specifications. The original con-
tract provided that the length Of sew
er should be determined by measur-
ing along the center Of the sewer de-
Quoting all manholes. The second
contract, under which the extension
was constructed, provided that the
measurement should be from center
of manhole to center of manhole. The
latter method was used for the entire
length of sewer. The contract pro-
vided that the price bid for manholes
included the necessary excavation; no
reduction in excavation was made for
the manhole. The quantity of exca-
walton was calculated from line one
and half inches below the bottom
Of the sewer; I can find no authority
for this additional inch and half.
1.-THE contract provided that in
case the backfill was returned with
out being consolidated, ten cents pei
cubic yard for all material thus re-
turned to the trench should be de.
Quoted from the price on earth. exca.
|. walton; no such reduction was made
nor was any reduction made in con-
sideration of the mortar cushion hav.
ing been omitted.
1.-THE original contract provided that
: in case of change in grade which
depth Of trench, the price bid fol
earth excavation would be increased
ten per cent for each foot Of increase
. or decreased ten per cent for each
foot of decrease. This clause is un.
fortunately susceptible to two inter.
pretations: Does It apply only to that
portion of the excavation lying be.
: tween the proposed grade and the
: grade to which the sewer was con.
: structed, or must it be applied to the
entire contents of the trench?
!: ''That portion of the. sewer which
extends beyond the limits of the orr.
. ginal contract I find to be 81 feet
, deeper on the average than that con-
/ structed under the original contract;
and it was evidently with a sense Of
fairness and desire to adjust mat
tiers by "give and take" method that
nothing extra was allowed for this