The Dorset County Express and Agricultural Gazette.
Dorchester, Dorset, England, 1885-12-22 00:00:00

THE D.RAINAOII,! SCHEME.

The Matron mad the flint Wainer was to receive
the report of the General Purpoeee Committee as to
their ',vent visit to the Salisbury Itrainsge Works
and decide thereen. They would remenite.r at the
1..• t imuting it was resolved that a deputation should
go to Salisbury and visit the drainage works dem
consisting of himself and any of the members .4 the
Council who liked to accominny him. On Friday
Is.st there were six members to meet him at the station,
in addition to whom were the Town Clerk and the
Borough flurvey.w. They went to the Surveyor...
"nice at Salisbury, and inspected the plans 4 the
town. and ascertained whet tither ',Articular. they
.111.1. They then went to the works, where the
Sorveyor and his son kindly ehow.el them over the
whole works, which were found to be Cillite witis
factory to every member ',relent. The working was
most simple, and out of the many places be had leen
to, there was nothing equal to that at tialislitiry.
There WWI no complicate I machinery .1 any kind.
Th,. er,weite flowed through strainers, and pawed on
through a mixture of lime, then poised out sigma
through tanks, and after that the effluent went to the
ri verquite se pure as any in any other jibee he I 5ip.,,,.
ttadd ill. in to that there wan not tlie slightest smell, and
11,. Surveyor told him tlwri. was no nuisance abut
r. He )the Mayor) considered if they adopted the
precipitation.y.tent their bestplen w.iiil.l inetenlitedly
to adopt the Oen as at Salisbury, and he was billy
convinced the scheme cmild be carried nut as a very
much reduced rate to their former estimate—at a sum
under 1:10,000. In addition tm that the working
expenses would be considerably reduced from the sum
that was estimated. Their former estimate WWI from
000 to 21,000 working esti/guys ; but if they adopted
the Salisbury wheelie they would not rennin. any
machinery, and the working expenses would. to about
£4OO, and putting one thing and another together, the
'chimes amid be carried out at Mot oew half of the
original mot. If that could be done he thonght they
would SUM their vomit to Solieleiry would Is. yell
mutt Ile only wished that all the member*
gone.
The Gimmittee's repewt Was as rollover :
" Your Gmenittee, am arranged to the last meeting
of the Town Council, have visited the works of aew,yg,
disposed in operation at Salisbury, where they wee.
tuet by Mr. 11... them., the city .surveyor, end emptied
with every information reverting the system of treat.
hien' adopted there. The system is .1 a mot niutple
wad comparatively inexpensive kind, and is one ot
Precipitation only. If adopted for Dorcheeter the
mucosity for the porch:see of additional land would be
rcmove4 as the three scree of land alreody secured
would be ample for all requirements. The scheme
received the eanction of the Local Government hoard
before carried out at Selisbury, and, am your Corn•
inittee are of opinion that, a similar one would Pally
satialy the neceseitieelof Dorchester, they have much
satisfaction in recommending the Gulled to adopt and
Garry out forthwith a ocliente bawd arm the Salisbury
system and to apply to the leual Government Board
for their sanction as poen as the rm.miuulsulut plans are
prepared fur eubmiesion to that authority. Your
Committee have directed the Surveyor to submit to
U.. Council with this report a repel from himself en'
pleining the details of the Saliebury echein..."
The repert of the Surveyor on the subject wee al..
reed sa :
"On Friday, December 11th, the Mayor (G.
J. G. Grespory, Emil, accompanied by kteiers. If.
M 'edea, A. Pope, A.. H. Lock, F. V. &me, W.
Tilley, G. Davis, G. flyniondi (Town Clerk), and
Walter Thomas (Borough Lriginter and Surveyor),
paid a visit to the Salisbury Sewage Works. On
arrival at Ssilisbury the committee proceeded to the
race of Mr. J. C.Mothania, C.E., the City Surveyor,
where the plane elf the sewers were inspected; and,
after venous information respecting the sewage
scheme had been given, the works were inspected,
and • detailed description of the same given by Mr.
J. C. Bothams and his son, who informed the corm
mittee that the population of the city .4 Soliebiary
was 14,000; the pewter, amounting tokiMM.ooogallons
• day, flowed by gravitation through screens to the
works, where it was treated with ft cwt. of lime per
diem, the lime being added in the shape of a liquid of
the cousisteocy of milk ; after the mixture had taken
place the roses flowed through a series .4 four tanks,
and thews into the river Nadder. By this treatment
the sewage warn so purified that the landowners below
the outlet have not complained of the same polluting
the river eines the works were 'forted in May
loot. The work, comdell of two screening clambers,

one or either of which can be used in connection with
the two sets of tanks; • gas holder; gat-making
house, where gaa is made on lgoveson's principle at a
coat of 2id. per 1,000 feet, which gas is only one-fifth
the power of coal gaa, so that comparing one gaa with
the other gaa actually costa la, OW. per 1,000 feet; an
engine house, containing two six-horse-power Otto gas
engines; a mixing house, in which is situated the air-
compresaors, tanks, lime-mixer, and slough pnas ; and
stores for lime, &c. ; two sets of four precipitating
tanks, with all neomsary valve gearing, by which the
whole or any of the tanks can be turd. These tanks
are worked as follows :—Tbe sewage is allowed to lam
into tank No. 1, in which is plumed a scum board ; the
sewage then flows over a weir at A into tank No. 2,
then over a weir at B into tank No, 3, and over
another weir at C into tank No. 4, which is also pro.
vided with a scum board then over another weir at
I) into the efnuent chambrr, which is provided with
balance valves to keep the nver water from entering
the tanks during floods, but these allow the water
(ruin the tank. to pas, into the river at all times.
During the paseage or the ...wage through the tanks
it deposits the greater part, if not all, of it. omlid
particles in the shape of a thick shah. Every week
tank No. lis emptied, the lepOule in it being I led
into a carrier and thence dotributed over l acne
planted with osier.; the deposit er slush in then re-
moved by suction from the tank into an iron cylinder
in the mixing house. Here it flows into a tank, from
which it is ferced by compressed air (at pressure .1
10011,. on the equiareinch)throughoneof.fohnson'ssluoh
preemies, which turns it out in the forty. of solid circular
cakes of manure la 'ample .1 which is now produeed,
also a sample of the eame which has been out of the
preen one neunthl which readily malls at 4.. per load .1
about a ton. This manure is valued at about equal
to farmyard manure, and Although 20 tons of this
meaner.- is made in a week the demand has In-n
greatu•r t..nn the supply. The cost ,of the works,
including alssit 2,000 feet of brick worms, was 114.900,
the contractor hieing about LIMO on the lertaking.
The above amount (lure not include the tout of the
land. Time working expenses per week mese follows :
—laluour, ; 1.2 10s. ; coal. El • coke. 3..;
oil svaste, 4s. ; press cloths, el 10.. —total, Wu rk•
ing expenses per annum : To esle
L) ;t.. sale of crops, 40; balance, 003 las.
total, rigs ICc.. Ily working expenses, kfilel
lem. The work.. comprise the leetit ammint
of inaehinery, and are the most pimple I have seen,
and if they continue to work as they are now doing,
I should consider them a perfect sue.,', I have
the pleasure .1 laying before you samples of the nude
sewage, as delivered at the works pn•viumus to being
,neeneel on the day the works were inspected ; aloe,
a aximiple of the effluent water, the elueh I,efore being
lammed through the filter, a sample of the eludge
taken from the filter, and a sample of the same that
had been out .1 the presa gune month. I atom lay
before you a sample of the sewage of lharchester,
Laken from the main sewer at the back of the
lrammar School, Charles-street, on December 14th,
Iflell.—l am, gentlemen, your obedient *errant,
WALTZR MICE.. 31.5.1., &c.,
Borough Engineer and Surveyor."
In answer to Mr. Burnett the MAYOR said that
sum would include the cost of all chemicals, which
were merely lime.
The Council then inspected a most interesting set
of modela of the Salisbury drainve, very ingeniously
constructed by Mr. Councillor Tilley.—Mr. IlreNerr
said the Council were much obliged to Mr. Tilley foe
the trouble he had taken, and suggested that the
models should remain on view in an ante-room of the
Council chamber for public inapectinu.
Mr. TILLRT expressed his williniMeria for this to be
done, but no definite steps were taken.