Evening star., 1939-07-17

M street NV, extending from
TWenty-second to Twenty-siXth
street, a minelike tunnel is being
blasted through solid rock to form
a link in Washington improved
sewer system.
The tunnel is part of the $3,71O,-
800 Rock Creek diversion project, an
undertaking designed to eliminate
large portion of the obnoxious pollu-
ton caused by overf1oWing sewers.
The whole project involves build
ing new intercepting sewer. part
open excavation and part tunnel,
from Plney Branch to the Potomac
River, a distance of more than 3
miles as the crow flies. More than
miles will be covered in the devious
course the sewer will take and the
entire project. including sewers on
both east and west sides of the creek,
will involve about 7la miles of new
line.
120 Feet Underground.
The work is now we'll under way.
Two contracts have been let for
work on the east-Side sewer. A part
of this involves tunneling operations
much more extensive than that now
being carried on along M street.
Some of the new sewer line will
run as much as 120 feet below the
surface, passing under the property
of former President Hoover on S
street and the Sheridan Monument.
The longest single tunnel a 1212-
foot circular, will extend from the
neighborhood of P street to the
vicinity of Belmont road, distance
of 4.l00 feet. Work on this tunnel
has not vet been started.
One phase of the undertaking on
the east side, on which work is
we'll under way. involves changing
the course of Rock Creek at the
bend near the P Street Bridge. The
course of the stream is being
changed for two reasons: First, to
give better line for the new sewer,
and second (and the primary rea-
SOM to provide larger play area
on the east side of the creek. Engi-
neers estimate a substantial saving
will be effected by changing the
stream now in anticipation of future
playground needs.
Treatment Plant Not Needed.
The general purpose of the Rock
Creek undertaking is to intercept
all sanitary overflow and prevent it
from being emptied into Rock Creek.
The overflow will not be carried to
a treatment plant. The large sewer
line that is being built, which is
as much as IA feet and 6 inches in
diameter in places. will carry it to
the Potomac River where the di-
luton will be so great, engineers say,
that there will be no pollution prob
lem.
Nor will the undertaking effect
complete removal of storm water
from the creek. The cost of doing
that, it was pointed out, would be
prohibitive. Two or three times a
year, it is estimated, there will be
storms of such intensity that the
relief sewer cannot carry it. But it
is believed the wash in the creek
uIlucl QUILL SlCulIlotollCCo VIII VIC oO
great that the overflow will be
carried off without the usual dis
turbing results from pollution.
The development will not make
Rock Creek fit for swimming, engi-
neers said. Enough contamination
will reach the creek in spite of
everything that can be done, it was
pointed out, that the water will
contain an unsafe count of bacteria.
However, when the project is COM
pleted, the stream will support fish
life.
The work is being done under
several contracts. The first, small
contract, covered borings along the
entire line of sewers. After the bor-
ings the work was let in five con-
struction projects. three of which
are now under way.
One of these is the M street un-
dertaking, or the Slash Run lateral
When completed it will be a tunnel
1850 feet long. Its major portion
will be an 8-foot 6-inch horseshoe.
Blasting Little Noticed.
The men excavating the tunnel are
working from two shafts, one at
Twenty sixth street and the, other at
Twenty second street. Some phases
of the work are carried on "a hours
a day. but so expert are the men
that few persons know of the blast
ing going on A feet under the much
travelled M street.
The east side sewer, providing gen.
eral drainage for the east side of the
creek, is being built in two sections.
The first section of the project runs
from the Potomac River at H street
TO Iwenty-fourth and N streets NV,
distance of 4,140 feet.
Inc second section, 1885 feet
long, will extend from Twenty
lourth and M streets to the bridge
at sixteenth street NV. Work on
thls section was started July 10.
Inc west side sewer will run from
!nlrtletn street and the Potomac