Los Angeles herald., 1907-03-31
Z


of Inglewood, and in communication
No. $685. signed by John Rebman l
have the honor to report as follows:
The route proposed is as follows,
quoting from communication No. 5S6:
Commencing at a point on the upper
end where the grade line of the present
new outfall sewer if extended from it's
intersections at Vernon avenue would
strike the hills. in the continuation of
said avenue on the land of T.. j. Bald
win; thence following as nearly on a
contour as the grade would permit the
base of the hills to the south and west
! crossing Centinela creek at a point
about one mile below the brick spur;
thence on a line almost due south to
connection with the present location
of the new outfall sewer in the town
of IngleWood.'
geographically Impossible
"Obviously the most economical
sewer on the proposed route is the
most direct on the greatest grade OBJ
tainable. A careful study of the ground
and of the topographic maps of the
United States geological survey shows
that the shortest practicable line on the
route suggested is 1856 miles long,
with a total descent of % feet
Surveys made by the engineers de-
partment show that the ground falls
off so rapidly toward the west from
Vernon and Arlington in the first three
fourths of a mile that the top of the
proposed sewer will be Az feet above
/ ground for q distance of 5000 feet, with
a maximum of ~ feet for 1000 feet
| where it crosses the marsh east of the
| low hills along which the proposed
route lies.
in order to provide drainage for the
j country to the south of the proposed
sewer it will be necessary to construct
1t high enough above ground to per.
NIT drainage under it, or to place its
| top at least as low as the surface OF
the ground. In order to carry this
| drainage over the sewer it will bt
necessary to drop it feet at this poin
below the uniform grade from the be-
ginning to the end of the proposed
route. This amount, feet, subtracteC
from the total descent. leaves but i
feet, the fall available in 1885 miles.
obviously sewer on such a grad
IS impracticable, and hence it is no
feasible to lower the sewer at thi
point.
IF CONSTRUCTED ON THE HIGH
GRADE IT WILL BE NECESSARY
TO PROVIDE A SUITABLE FOUN
DATION OF CONCRETE OR OTHEI
MATERIAL, TO COVER THE SEWEI
WITH AN EARTH EMBANKMEN,
WHERE ABOVE GROUND AND TT
PROVIDE FOR SURFACE DRAIN
AGE.
Expensive Trestes Needed
From the point where the propose
. sewer would reach the base of tn
hills to a point about five miles fror
the place of beginning, constructio
would not be difficult, but beyond tn
, line would follow along a steep hill
, side for more than three miles am
, then across a rolling country intersect
ed by many small valleys or raYine
until Continela creek is crossed at tn
point designated in communicate
"AT THIS POINT THE sEwE,
GRADE WOULD BE ABOV
GROUND MORE THAN TWENT
FEET AND THE SEWER WOUL
HAVE TO Bic PLACED UPON
LONG LINE OF EXPENSIVE TRES
TIE WORK.
ITO locate a line on a contour as sul
gested would increase its length abol
1,S miles, reduce the gradient and il
crease the size of the sewer,
ION THE LINE SELECTED /
WOULD BE NECESSITY TO con
STRUCT 800 FEET OF TUNNEL AN
MORE THAN 1000 FEET OF con
CRETE TRESTLE WORK IN ORDE
TO CARRY THE SEWER EITHE
UNDER OR OVER THE SURFAC
DRAINAGE OF THE COUNTRY.
The grade OF the proposed sewer, b
4 ing 2,37 feet per mile, would be fix
by that of the new outfall al "
i points, one at Vernon and Arlington an
the other at the terminus of the pr
posed route. In order TO have the san
capacity as the new outfall the pr
posed sewer must have a diameter
6.5S feet inside.
Will Cost $393,78 More
THE estimated cost by the engineer
department OF the proposed sewer
$964,OOO of which s479 $50 is the cost