Evening star. [volume] (Washington, D.C.) 1854-1972, 1890-05-21

| Of its water shed above Barking being not far
from 5000 square miles. The dilution afforded
! by the huvial discharge Of tho river during the
| extreme low stage is about ~ gallons per head
per day. The works at the Barking outlet for
precipitating sludge from the sewage before its
discharge into the river are nearly complete
and were visited in June last. 1t is proposed
TO add to the sewage grains of lime and
gram OF suiphate OF iron per gallon before 1t is
| discharged into the settling tanks. which cover
| superficial area of 9 acres. After the deposit
| OF sludge the effiuent is to be discharged into
\ the old reservoir, to be discharged into the
! river upon the ebb tides The sludge
| Is to be pumped into an elevated reser-
voir. from which 1t will be deposited by gravity
| into barges, to be by them carried to and de-
| posted in deep water at sea. The precipIta-
ton works have capacity for treating 90. 600 900
| gallons Of sewage per day. The London
| sewage was discharged prior to 1868 into the
| river along the fronts OF the city by sewers
serving natural drainage districts and for
many years the nuisance caused thereby and
the best method of disposing of the sewage
were subjects of controversy until the plan
proposed by the engineers of the metropolitan
board of works was adopted in the year 1858.
This plan provides for intercepting the sewage
! and carrying it to Barking and Crossness re-
spectlvey and its discharge into the river upon
ebb tides. The works contemplated were COM
pleted in the year 1865 at an expenditure
amounting to $23000.000. These works were
hot many years in use before complaints were
made OF the pollution Of the river from the
sewage. and after Investigations and parliament
tary inquiries extending from the year 1868 to
the year 1884 the precipitation of the sludge
and the discharge of the effiuent upon the ebb
tides was decided upon and the works for the
same are now nearly complete.
Going next to Coventry he found that the
sewage treated per day amounted to 235 600
gallons. The sewage is passed through rotary
screen to remove the grosser impurities before
arriving at the point OF application of chemicals,
which are sulphate of alumina and lime, the
proportions being varied according to the
Judgment OF the local manager OF the works.
The ettiuent is then filtered through land upon
the intermittent principle, but on account of
the insufficient area of the filter beds the
etfiuent is discharged directly into the river
Sherbourne without filtration between the
hours of IL midnight and am. The sludge is
compressed by means Of filter presses, the
hydro-pneumatic system being used for pump
ing the sludge.
THE SEWAGE OF PARIS
His last visit was to Paris There he
found the estimated amount of sewage
to be 100000 gallons per day.
About 300O0,000 gallons Of sewage per day
is pumped at Clichy and sent to the irriga-
ton farm, the remaining portion of the sew
age being discharged into the river Seine
below the city. The area of ground. which is
increasing every year. now being irrigated is
about 1000 acres. The sewage does not con-
tam very large amount of solids, as these are
to large extent retained in cesspools before
the sewage is taken into the public sewers and
no further precipitation of sludge is attempted
before the sewage is sent to the sewage farm
The farms are usually laid off into beds by
bitches, which carry off the sewage which is
absorbed by the earth as it passes along these
bitches. The ground cultivated belongs, with
the exception of a model farm belonging to the
city, to private land owners, its character be-
ing OF a fine sandy alluvium. which irrigation
has redeemed from desert-like plain to be-
come a fertile market garden. 1t is expected
that it will not be long before a suffi-
Gent area of this land will be
cultivated to demand all of the sewage from Paris
and thus save the Seine from its polluting
effect An objection to the method of disposal
by farmers who can Use the sewage or not as
each one thinks best, would seem to be that
during wet weather and periods succeeding wet
weather q large portion of sewage would be
discharged into the river without being passed
through the land At such times, however
the amount of water in the river would proba-
bly, be sufficient for the publication OF the sew
age thus discharged. The sewage is passed
over the ground during the winter season, when
no crops are growing, the farmers claiming
that the ground thus becomes enriched for the
ensuing seasons crop. The effuent from
the model farm at the time of his visit, he
said, was remarkably clear and bright.