Delaware gazette and state journal. (Wilmington, Del.) 1883-1902, 1894-08-09
WlLNINGTON'S NEW FILTER
For Purifying the Supply of
Drinking Water.
METHOD OF ITS CONSTRUCTION
Will Purify 100000 Gallons
of Water Per Day.
Three of Its Five Sections Have Already
Been Practically and successfully Oper-
atad-PhiIadelphia Oniclals Interested
In the Filter and Will Carefully Inspect
Its Workings.

Water Department is now practically
completed. The plant was designed by
George H. Sellers, an engineer of this
city, and with the exception Of one at
Tacoma, is the only one of the kind in
this country, if not in the world. 1t
uses the sand and gravel bed, tiltering
from the bottom upward, the puritica-
ton being secured by iron punchings
and aeration beds arranged in series
Of large iron. troughs before the water
reaches the filter beds.
The plant is, with the exception of
the entrance house, completely under
ground. 1t is divided into five sections, !
each with minimum capacity OF
100000 gallons day. Three Of these
sections have been completed and run
ming for several days, and the other two
will be ready for use inside of several
weeks.
The water to supply the works is car
ried by race or canal from dam on
the Brandywine abputa mile above the
city. From the intake basin on the banks
Of the canal large iron pipe carries the
water 10 the i've tiltering beds, which
are similar in every particular. They
are constructed in five long tunnels of
solid masonry, connected with large
passageways at each end. Tho water
when first received is let into large
cast-iron eiector, the top OF which is
supplied with six funnel.shaped OPEN
ings arranged around the side opposite
that where the water enters. lii the
centre is large circular air pipe rising
several inches above the other openings.
AS the water pours down the tunnels 1t
produces enough suction to draw
through the central opening all the air
required for the aerating process.
From the injector the water is car
IiCd out on to II broad, cast iron trough,
l25 feet long and about y feet wide.
Rows Of thin sheets OF combination
OF iron and copper are suspended from
rods across the trough, hanging down
into the rushing water Alternating
with these rows are iron screen boxes
, containing the iron punchings and sub.
merged when the plant is in operation.
, The metallic sheets and iron punchings
alternate for over half the length of the
trough when the aerating beds begin.
The air which Is drawn into the in
, jectOr is carried along the bottom Of the
trough in cast iron chamber. Tie
aerating beds consist OF iron pipes, rising
from the bottom of tle trough and bent
over at the top. Through each is drawn
d current Of air from the chamber be-
meath, which bubbles up through the
water as the pipes are submerged.
/ Small sheets of iron fastened to the sides
1 of the trough AZ an incline throw the
water over onto the air ducts, and at the
same time aid the work Of publication
by churning it up and keeping all par.
Q tlcles of the water thoroughly mixed up
v At the end of the first trough the
water shoots down into u second, which
e is Immediately underneath, and runs
!. buck again to the base Of the injector
h Throughout the entire length Of thi;
4 second trough small iron pipes run from
/ the air chamber, attached to the trough
o above, and force currents Of air through
the water, keeping IL in continuous
# bubble. AT the foot Of the Injector, til,
e water, after passing through the secon,
n trough, separates into two streams, aut
g is again carried the length Of the tunne
is IN smaller troughs, one on each side o
o. the arch. AT the farther end eacl
e stream is again divided into two as the
run into the four openings leading dow
TO the water chamber, under the iilte
bed. This chamber has a solid concret
bottom and sides, and Is "a inches higl
y. - It's top is four.inch IRON crate, o
~ which the filter bed rests.
II Tho filter ped, which extends tn
8 entire length Of the tunnel, has filtel
U ing surface Of 1900 square feet, and
d, SO inches deep. Resting directly on til
y crate ~ the bottom Of the filter is be
y Of egg gravel, 3 inches thick then CON
= = inches Of nut gravel, 4 inches of ches
~ nut gravel, inches of pea gravel,
~ inches OF shot gravel, 5 inches Of coars
y sand, and finally ~ inches Of fine SAM
= As the water rises in the well leading
~ the water chamber 1t forces that in I'll
q, chamber up through the filter until
II, stands ON top Of the bed to the depth
~, nS II inches. II then runs through Il
~ overflow channel into clear wat
- basin, from where 1t Is i'll turn carrie
to the pump well in the old water worI
aud pumped up into tho reservoirs.
at While the water is in the clear wat
IS. basin it is again aerated. This is Il
fill only Instance where pressure is used
nd force air through the water. a lar!
'2l iron air.pipe rests on the bottom, Al
~ by forcing air through 1t the water
TX the blsin can be kept in continu
in bubble.
len The filter bed is cleaned by revcrsit
las the water. For that purpose the bed
ry. divided into four equa! longitudiu
oil sections, and i'll order to clean il all t
UT water on top of the entire bed is fore
~ back through one Of these section
tic This is repeated until every one Of t
no sections has been cleaned The fl
ms quency of the operation Will depend
II u the character of the water, but 1t is cs
mated that once "A day will be ample.
The plant takes up comparative
" little spacc, the inside measurement
u " the entire structure being but ll2 feet
~ inches by OS feet. The cost was Origina
~. estimated ut about $4,000, but consid
~. ~, able blasting was required 10 reach
~ necessary depth, increasing the cost
~" ~. about $4,000 The cost Of operati
-" will, it is thought, be comparative
~ slight, as il is estimated that one IN
" can attend tO the entire plant, a
. .Tu under the system of washing tho
NJ NJ renewals will be required only at 10
intervals.
Experts who have seen the plant
gard il very faVorably. Tho wal
after passing through one of the beds
,ynr clear and sparkling, and when tho ent
,scd plant Is completed and In operation
bia will furnish the city with an am
nm supply of pure water, Dr. J.
,al Thomas of Glrard College, PhilldUlpl
in examined the plant several days a
oen and was much pleased with 1t. Dlrec
,oa Windrlm, Chief Ogden and other Phi
ado delphia officials will probably nsper
nd some ulna during inc present we
} be Estimated on inc COSY o. lhe " inning
- Al, tA., .i..I