The record-union., 1897-05-25

the house drainage south of 5, nofth
to the S-street sewer at Twenty-nlnth
and Twenty-fourth streets, but not
storm water, the grades being unfavor-
able The Seventeenth-street sewer
south of S may be used for house drain
age when future needs require it IN
that locality At Thirteenth street
fourteen-inch pipe is deemed sufficient,
and at Ninth a twelve-inch pipe south
of S street will carry the drainage.
At Sixth street there is considerable
surface water coming from low lots
north of Y street; therefore an eigh-
teen-inch pipe is specified. At Second
from s to Y, an eighteen-inch pipe Is
specified also on account of the low
ground and to drain Brannan's Addl-
ton.
All lateral sewers shown on the plan
to be constructed at some future time
are not included in this estimate for
the reason that they may be construct
ed as the localities to be benefited re-
quire under the provisions OF the Nroo-
man Act, whereby the cost is assessed
to the property fronting the improvement.
They are shown to be placed in the al
leys, where it is presumed they Will De
the most convenient for house connec-
tions, and where the nature of the paw
ing and Improvement is such as 10
make the cost of construction the
cheapest.
1t would be impracticable to place
lateral sewers in the streets in this city
ON account of street improvements that
have been made.
ha dica acfr
streets, not only in laying the sewers,
but also in making the numerous con-
nections from property adjoining
In the plan presented the capacities Oh
the main sewers are determined upon
the volume of heaviest rainfall 10 pe
taken care of and the rapidity win
which it finds its way to the sewers;
but with the lateral sewers there be-
ing only house wastes to care for the
capacities are made uniform and SUI
ficiently large to avoid cloggfng.
The six-foot sewer at Front and )
streets is designed to carry the entire
drainage of storm water and sewage
in the city and also large percentage
of seepage water south Of S street from
Front to Eighth.
Taking the United States Weather
Bureau reports the greatest amount OF
rainfall for a season between the years
1919 and 1896 is about thirty-siX inches
and the greatest for any one month is
about fifteen inches or about half an
inch in twenty-four hours. Assuming
that one inch Of rain falls in twelve
hours we will allow that it Will require
only eighteen hours for it all to reach
the street sewer within the area well
built over and paved, viz: Front to Fiji
teenth street and from street north
to b street one inch in depth over this
area drained off in eighteen hours and
allowing ten per cent. for absorption
and evaporation would equal about
>, 100 cubic feet per minute.
The area east Of Fifteenth street from
B to and south of from river to
Thirty-first street on the average is
not closely built over and the grades
are comparative fiat so that the rain
fall will find its way to sewers slowly
and a large percentage also Will be
evapOrated and absorbed so that it will
be safe to assume that one inch falling
in twelve hours would require, we win
presume, twenty-four hours to run off
and that twenty-five per cent. is evap-
Grated and absorbed, which is a small
estimate, would equal about 3.400 cubic
feet per minute. The six-foot sewer
| is designed to carry about 5000 cubic
feet per minute, leaving an excess ca
pacity of 800 cubic feet per minute to
carry seepage water and house wastes
or sewage.
From five to ten per cent. of the total
capacity of sewers is allowed for house
drainage.
The S street sewer diminishes in di-
ameter as it projects eastwardly to suit
the amount of drainage to be received
At Seventeenth street the capacity is
about 2,400 cubic feet per minute, and
the area to be drained would be about
| equivalent to that amount allowing fol
rainfall as hereinbefore stated
| From Seventeenth street the proposed
| sewer gradually diminishes as it pro-
| jects eastward along S street to it's ter
minus at Twenty ninth street, where g
24-inch pipe is deemed of sufficient size
| to carry the drainage.
| When the streets in the northeastern
| portion of the city are improved ant
! catch basins are constructed to con
duct the water to the sewer this local
ity will have no cause for complain
about poor drainage and in the bushes.
| portion and closely built sections Of tht
city where sewers are now constructed
good drainage win be obtained by the
reconstruction of the Ninth and Thir
teenth street sewers and also by the
adoption of the flushing plan hereir
contemplated. By the latter plan tn,
objectionab ble cesspools may be abol
ished and a rapid means of sewage dis
| posal will be secured, which will i'm
prove very much the sanitary condition
| Of the city.
In order that the present pUmpins
plant may be made perfectly efficien
for the heaviest rainfalls when the new
| sewers are in operation, and in orde
that we may have a reserve in case o
accident to present pumps. or machin
cry il would be advisa BILE to put in al
additional pump at the plant with suit
able motive power.
The cost of the same is included il
the following estimate of work to b.
performed as per plan
Extension Of the S street
sewer from Seventeenth
to Twenty ninth. ......S 20, ,461 o.
To reconstruct the Ninth
street sewer from alley X
and L, north. ....... 5,3S5 o.
To reconstruct the Thir-
teenth street sewer from
street north. -. 1O,94s o.
Extension of Seventeenth
street sewer north two
blocks with 12-inch pipe. LOSS o.
To construct Twentieth
street sewer north from S. 13,261 O
To construct the Twenty