The Dorset County Express and Agricultural Gazette.
Dorchester, Dorset, England, 1881-09-13 00:00:00

THE NEW DRAINAGE SCHEME

Ms Borough surveyor presented lb* plans sod
schwas proposed; a whta, lb. following is a brief
ratans. (We hays not spays to give th• whole
&ammo* labial was al so wthawatirs obankatax.)

" Gentlemeo,—ln conformity with the instructions
received from you in August last I have very carefully
considered the whole of the matters appert zining to the
coustruction of a system of sewerage for your district,
and on the accompanying plans I have laid down each
• system of sewers and other works, SS will be
sufficient for the payment and the prospective require-
ments of the borough of Dorchester. At the Marna
&lons conveyed to me pointed out the mode which
I. should be adopted for the disposal of the sewerage, it
will be needless for me to here enter upon the special
advantages of the mode of disposal which you have so
wisely resolved should be adoptid. Therefore I will
confine myself to the special merits of ths scheme
delineated upon the plans already reterrel to. In
designing a system of sewage for any district it is
requisite to take into cansideration—First, the area of
the district; second, the rainfall of the district; third,
Its geological character; fourth, it, oyaia al outline;
fifth, the present and prospective numuer of its popula,
tide: sixth, the water supply.
"With regard to the area of the borough, • great
portion of the 4,160 acres which it oomprised was
available for building purposes, and coattail &sins must
be provided for, as well as for the densely populated
districts of the borough. As to rainfall, am much as
two Moho have been known to fell In the borough and
neighbourhood within 24 hours, and having regard for
these excessive rainfalls it will be necessary that due
provision shall be made in the surface drainage sewers
for such amount of rainfall. _

'Geological Charsoter.—The Borough of Dorchester
Includes in its geological chaiacter th, hard or rock
chalk, interspersed with flints, and a chalk of a softer
kind and therefore lees compact in its formation •
whilst in the meadows at the east sod of the town ths
strata is composed of loam gravel, sad gravel combined
with marl, and in places a fluid chalk is met with.
"Physical Outline—The physical outline of the
Borough of Dorchester is highly favourable to the con-
struction of sewers, as the falls in many place' are so
rapid that sewers of a comparatively smali sin, can be
used far the drainage of a large area. On the other
hand, u the districts in some parts fall in direct
opposition to the fall of the main outfall sewers, which
renders • mach greater length of Dowers necessary than
i. required in the district. In the scheme proposed
special precautions have been taken in order to procure
tb• perfect ventilation of the sewers, so as to prevent
the transference of the sewer gas from one locality to
another.
_

Poj'oulation.—The population of Dorchester seems
to have increased but liWs for years previous to 1871,
when the population was 6,915, but moos which date
It is estimated to have benumbed by nearly 1,000,
otaltiag a total in round numbers of 8,000 inhabitants,
.ocupying 1,248 holiest, the military dsjast °sake, the
Royal Hone Artillery Barracks, and tier Majesty's
Prison.

_
" Water Supply.—For all purposes of this report the
water supply he. been takes at Motions per head per
day of the pixilation.
" Old Sewers and Outle.—Under this head Mr.
Thomm referred to the various manholes and ontleta,
from which it was seen that water other than sewage
finds its way into We main sewer, all along its course
but in the greater quantities between the London-road
sod the -let in Mr. Sharron's field.
_ . .

"Sewers.—The whole system of the sewers set forth
on the plans may be divided into three sections :
First, the intercepting or low leirel sewer.; second,
the high level sewer; third, the surface drainage.
The intercepting sewer will commence at the manhole
in Miller's Close, close to the boundary wall of the
Royal Hone Artillery grounds, thence to Grove-
buildings, North Walks-road, by the fields, Prison
grounde, and Orchard-street, to High East-street.
Then along High-street, Fordiegton, Cuckold'.-row,
Holloway, and Steadfast to Fordington-croes. The
high level sewer will commence at the Bridport end of
the Cornwall-road, panting along Cornwall-road to
Great Western-road, where it will receive the Victoria
and Idsumbery-road sewers, thence down Great
Western-road to the Weymouth-road, where there will
be constructed a storm water weir, by which means •
great quantity of the waste water from the malt house
will find its way into surface drainage. From this
point the sewer will pew along Sauth Walks-road,
leen Way, and King-street, to Fordington.cross, where
it jo!ne the intercepting sewer. From this point the
main outfall peases along East-street and Loud's-road
to the waren works. Three sewire are constructed at
such a depth below the surface of the road that the
existing sewers may be connected with them, and they
are of sufficient capacity to carry away the drainage
of houses that may be built within the borough for the
next 50 year'.
"Surface Drainage.—All rain water which may fall
within the borough will as far 1111 valuable be kept out
of the sewers, and conveyed by a separate system of
drains to the nearest watercourae. The surface water
from the Cornwall Estate, Weymonth-rosA, Trinity
and South-streets, Wolin/40DM* &0., will be con-
veyed in gland socket pips@ to the Mill-leet by Swan'.-
bridge; that from the barrack, and Bridport-road down
the quarter of Grove-building.; that of the higher end
.d High West.street down the quarter of Shirehall-
lane ; that of Princes, Trinity, and High West-streets,
Pease-lane, and North Square, down Friary-lane, into
the Mill-last; whilst that from Forlington-oron will
be conveyed by • new culvert about 150 ft. further
d .wn the Mill-last than where it now enters it, by
which 'meas.& better fall and outlet will be obtained.
_

"Sewage Works.—The sewage works will consist of
a boiler-house, engine-house, noel and chemical sto=
press-room, fitters' shop, office, and pumping
mixing-rooms in one block; next of • nest of four
precipitating tanks in another, and a smith's shop in •
third; whilst at the entrance to this works will be
suitable gates and a manager's residence, containing a
committee room and parlour, a kitchen. out-offiose,
and bedrooms. In the engine-house will be plsoed
the old engines from the waterworks, which will be
required to drive shafting instead of pumping, as
when previously at work, whilst the old boilers from
the waterworks will be reset in the boiler-house.
Previous to the sewage entering the sewage works, it
will pass through a straining tank which will be open
at the top, and into which • certain amount of purify-
ing chemicals will be introduced, by which means any
foul gam that may arias from the sewage will be purified
and disinfected. From this chamber the sewage will
flow into • tank, which will be constructed of such •
size that it will contain the sewage that may flow to
the works during the night, and thus obviate the
necessity of pumping night and day. This tank and
the various parts of the system will be so constructed
as to keep out the surface water, by which means
sewage alone will have to be treated with. The 'sewage
will be pumped from this tank by means of two con-
tractors, or chain pumps, into the mixing tank, where
more chemicals will be introduced, and from thence by
means of the channels and apertures into precipitating
tank No.l, where • scum board will boplaned. From this
tank the sewage will pees into tank No. 2, and Untrue
into tank No. 3, when the water will pees into the
effluent channel and on to the river in a purified state.
When it is necessary to empty tank No. 1 the water
from it will be removed by 13304111 of • floating syphon
into tank No. 4, and the sewage will also be turned
into this tank; when the water he. been removed a
valve in the tank, situated in the block at the centre of
the nest, will be opened and the sludge forced down
the inclined floor of the tank towards it, whence it will
be drawn by • pump to a tank under the press chamber
and thence pumped into the prase and turned into dry
cake manure ready for sale. When tank No. 41. in
use in ornnection with tanks Nos. 2 and 3 the sewage
will be taken from tank No. 4 into tank No. 3 by
means of the slalom at the centre of Soonest, by which
means the tanks can always be need in rotation.
When tanks Nos. 2 and 3 require to be emptied& valve
in connection with the floating strainer will be opened
and the wa.er allowed to pun into the river. The
whole nest is so well supplied with valves that any of
the tanks can be used at will. From the engine room
through the store rum into the press room shafting
will be suspended by which the various portions of the
machinery will be dr:ven. In the engine room a force
pump will be planed to raise water into • tank placed
in the mixing room. In the mixing room will be placed
a mixing trough and two vats, into which the mixed
chemicals will he placed airl diluted with water before
flowing into the sewage. This mixture will be kept
from settling by means of rotary anus driven by tin
before named shafting. I estimate that tanks No., 1
and 4 after having been in use for • week will require
to he cleaned out, and tanks Nos. 2 and 3 once a fort-
night; also that one ton of manure at least will be
made per week.—l am, Gentlemen. your obedient
servant, WALTER THIN AIN Ass ,c. Borough
Engineer and Surveyor."
The next question was to receive the report of the
General Purposes Committee on the drainage question,
and generally as to the Surveyor's plan. The report
WAN as follows : . -

"Since the last meeting of the Council your com-
mittee have further considered the drainage question,
and the Surveyor hae completed hie Wane of the pro-
posed works to be construes I at the °octal, which
are rubmitted to the Council for consideration and
adoption with this report. Th, precise method for
treating the warfare at the outfall has not been decided
upon, but the Town Clerk of Salisbury has been com-
municated with for the purposo of airertaining what
system is empl,yed there and with what income. In
reply, your committee have ta en intormed that at
Salisbury the Sodium aystann of treatm.nt devised by
Mr. T. H. Smith, the borough survey,4' of Taunton,
has been adopted, and is considord by the municipal
authorit lee to be • success. As rrg acts the site for the
required works. your committee are not in • p aition
to recommen 1 for adoptioa the terms offered by Mr.
Taylor. which bays been slightly altered. Mr. Taylor.
through his Policit rs, now offers to sell his interest
n the Lond's Mill premises to the Council for
IMO, the sum originally named by him, with
the addition of £l5O to be paid as cowmen-
Nation for the exp mews to be incurred by him
in relinquishing the premises, or he will still submit
the question of value to arbitration provided the
question at dilapidation, under his lease is not tiken
into aoxpant. Your c immitt a have as ti an alternative
site been ic communication with Mr. Howard respect-
ing the piece of land, amounting in the whole to
about ten scree, which lime between the Loud's-mill
property and the South-West!rn Railway, and have
ascertained that it is available for nurehaw with Inc.
mediate possession, and that • smell portion of about
two acres, being the quantity which the committee
considered sufficient, might be obtained reparste'y.
Mr. Howard, however, states that it ii indispensable
that an oiler for the land required should by made, as
no price can be given. Your committee therefore ask
that power may be conferred upon them ti make an
offer for any portion of the land which they may think
desirable, and generally to treat with Mr. Howard for
its purchase. The committee submit to the Council
herewith also two letters—one from the Rev. W. Allen
and the other from Mr. Lock, the clerk to the rural
unitary authority—both on the subject of the drain-
age."

Mr. Aldermen Gauls said he should be very
pleased to move the adopthm of the replrt. He
considered they had now a very just offer, and.
although they were called upon tq name the price
themselves. at all evente they had as alternative. It
wee very evid•ne, from what they had heard, that Mr.
Taylor was driving them, each time they common-
tested with him, herder and hatch r, and this question
of dilapidation might involve them in very consider-
able @spews. The terms in regard to the site of the
Loud., Mill wan serious enough, but when they came
to add to it the 0014 that this might Involve Aso le,

he was greatly in favottr of the sanction of the
Council being given for the purchase of the land. He
thought, at first, that the laud, tea acres, was to be
cold metre, but it appeared from the letter of idr.
Howard, that he was prepared to receive an offer foe
any portion of it. Re thought. they inigrlit make forms
for, say two acres of It, wMch would be quite ample
for them. There was a road to it, and he thought
they could obtain the land without much outlay, and
as Lb. price was left to the oommittee, lie did not
think would be disposed to give more than the
lead would be worth. He would prop os that the
report. which 017 had jut heard, b 3 adopted, and he
hoped the OglUlni I would give full sanction to the
committee, to enable them to enter upon this question
without any delay whatever. He thought that under
it.y dreamt mom, even supposing they obtained the
Luid'a Mill site afterward', the obtaining two ACM. of
land would not be iii; anon. to them, for it would most
probably be worth fully the money they gave for it.
With regard to the treatment of the sewage, it
appeared from what he hal heard of what was grsnted
to the Salisbury people, that the matter of delay need
not be so great al was expected. From the moon
which he hell in his head. ia regard to Salisbury, when
the =litter of the proposed new sewage wa• brought
forward and the presented, a letter MN re-
ceived from the Government Boma to this
effect " I am directed by the I,cal Gorernmeot
Board to forward to you herewith their sanction to
the borough and the Town Council of Salisbury of the
borrowing of the sum of £IO,OOO for works of sewage
and sewage disposal; at the same time, I am directed
to inform the Council in giving this sanction, the
Board in no sense bind themselves to an o:pr...ohm of
opinion as to the proposed works. If, when completed,
the works failed to satisfy all the requirements of the
Act, It would Mill be incumbent upon the Town
Council to comply with the Act." He (Alderman
Galpin) oontinued they ought to get some answer as
Saltebury, and they ought, if possible, to lose not a
moment in laying their plans before the Board and
asking their sanction. With all due respect to the
legal gentlemen, be was sorry it took so long to move
from step to step. If they had an alternative site, he
beUeved they would get on more rapidly than they
would otherwise do. .

--The -131d4ii:T-o—wn Cllll nimarked he had wen
Hr. Taylor's solicitoe, and he had ioforgied hlni that
he was willing to submit the vitiation of dilapidation
to arbitration

Alderman Gauss : If Mr. Symonds had said that
before, I should hive spokes more strongly on the
matter. I hope we shall notnowheaitate fora moment
in trying to get the other site.
The fo.lowing was the motion submitted by Alder.
men GALPIN : 'That the report of the General
Purposes Committee, with the pleas for deal ng with
the new sewage scheme submitted to this meeting be
adopted, and that the oommittee be empowered to
treat generally for the purchase of the laud belonging
to Mr. Surd en, near the Loud's Mill premises, and
to take all other neosesary steps for obtaining the
sanction of the Local Government Board, of the plans
and scheme, and the granting of the loan to meet the
outlay to be incueed."
Alderman Davis seconded the motion. .

------- ------.
Alderman (lagoon!, who was in favour of the
motion, remarked there could not possibly be any
harm intreichati ng the land, for it would be worth the
vain. paid. And, besides, continued Mr.
Gregory, . Taylor thinks we have no other site, and
hale endeavouring to drive us to an extrendtr.
Alderman Gatzus : Whatever we do, don t let as
lose the chance of having an alternative site.
Dr. ALDIIIDOS quite agreed with • great dead of
what Mr. Galpin had said. It was extremely
necessary that they should proceed to do something'
the Inhabitants of the town were sadly inconvenienced
and exposed to great and serious risks by the continu-
ance of the present state of things. The report of the
committee had been drawn up very well, and it would
show Mr. Taylor UPI other people that they intended
to move forward. The offer which they now had was
on much better terms than that of the Onchy, for they
would be enabled to get • piece of freehold land will, h
they could hold for ever and ever, instead of having at
the end of about 30 years to be liable to give up the
whole of the land and the works. Mr. Howard had
intimated that the owner did not want a very remark-
able price, and besides that they were at liberty to
have titres or four acres, or just as much as they
wanted. Here, toe°, was their opportunity to set on
with the work, and be oat of the hands of the Duchy.
With Mr. Galpin, he urged them to adopt the repoit,
for he believed it was • move in the right direction.
The motion was then put to the meeting sod
carried.