The Corvallis gazette. [volume] (Corvallis, Or.) 1862-1899, 1890-02-07
WATER DITCH TALK!
Three Ways of Construction
Presented.
FIGURES WILL TELL
1t will Require Plenty of Digging
no Matter how Short the Dis
tance may be.

The question of water ditch has
been discussed so much during the
past year that it may not be amiss to
present some figures in regard to it.
The proposition is, we believe, to tap
the Wlllamntte river somewhere south
of the city Of Corvallis; bring the wa
tel out onto the prairie through race;
over Mary's river in fume, and dis
charge it onto turbine water wheels
along Corvallis river front.
We will suppose the distance be-
tween the surface of water in the race
on First street and tail water on The
surface of the river is twenty feet; it
would be more than that during the
summer and less during the high water
season, but, for our'calculation, we will
take twenty feet. In order that the
enterprise may be of practical benefit,
we ought to have water enough flow
ing through the best form of turbine
wheels to develop between five and
six hundred horse power, say $50.
This will require, if the fall is twenty
feet, 1900 cubic feet of water per
minute which would be enough for ten
small factories. To get this amount of
water, will require ditch of certain
size depending on what is called grade
in railroads but slope in hydraulics
Suppose we try slope of three feet
per mile. A ditch on this slope, 1877
feet wide on the bottom, 27.7 feet
wide on top and four feet deep, will
deliver 1919 cubic feet per minute,
if running full and no loss by seapage;
this is the amount we require, and if
all the conditions can be complied
with, is cheap ditch. 1t is believed,
by many, that there is point about
twelve miles south of Corvallis where
| the water can be taken out of the
river. Twelve miles at three feet per
mile is 36 feet, and with the 30 feet
to start with we have 20 plus SO or sc
feet, which is the fall the river must
have in coming from the / 2 mile point
to Corvallis; and if it has not this fail
it must be raised by a dam at the
| l2-nile point in orderto fulfill the con.
dltions.
AS it is probable that the river has
not this fall, and as the benefits to be
derived would not be worth dam Of
this magnitude, let us try ditch on 8
Tighter slope, say one and half feet
per mile. A ditch % feet wide on the
bottom, SO feet wide on top and 4 fee
deep, if running full and no loss BY
seapage, would deliver 1850 cubic
feet per minute, about the amount we
want, and the elevation of the river
at the l2-mile point must be Is plus
90 or 38 feet; if it is not so, dam
must be built as in the former case
Let us try ditch on slope of three.
fourths OF foot per mile. A DITCH
1872 feet wide on the bottom, 472 fee
wide on top and feet deep, running
full and no loss, would deliver l6,97(
cubic leet of water per minute; tbi
again is about the amount OF water
we want. The rise of the river mus
be 20 plus 9 or 30 feet from Corvalli:
to the l2-miie point. If the total rlss
of the river, in getting to any giye1
tpoint, does not carry it ap to the eleva
ton required by the canal at the sam,
point, water cannot be taken out with
out the construction of a dam, which
is the way the necessary head il
usually obtained.
| If we get water out of the William
ette, ID miles south of Corvallis o
any other distance, it will be by yer,
fat slope and very wide ditch for tn
| first three or four miles. G.
/ CORVALLIS, Feb. 4, 1890.
|
DTIDT Ir crunnT Nrnrry