1844.1 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



316 



'small stream, the drainage of the uplands. With this small stream the 

 sewer, with its slight fall, is kept perfectly clean ; no accuriuilations of any 

 kind take place in it -, and 1 think I may assume, therefore, that a fall of 

 two inches in 100 feet, with a good backwater at frequent intervals, would 

 be sufficient. With a fall of two inches in 100 feet, in a length of 4,000 feet, 

 the fall would be six feet eight inches. Now 4000 feet is rather more than 

 three-quarters of a mile ; throughout which length from the river the sewers 

 of the district alluded to might be deepened to three feet above low water of 

 neap tides at their outfalls, rise at the rate of two inches in the hundred feet, 

 and leave six feet ten inches of depth from the bottom of the sewer at the 

 upper end to the top of high water of spring tides. A reservoir, formed in 

 any convenient place inland, near the heads of the sewers, and connected with 

 the river by cast-iron pipes or with a brick culvert, may be filled to high 

 water level at every flow of the tide. The water being penned back, there 

 will be in the reservoir from five feet to six feet six inches in depth above 

 the bottoms of the sewers at their highest, available to scour them when tho 

 tide shall have ebbed in the river below the outfalls of the sewers, and a 

 scour may be thus effected once in every 12 hours, often enough to render 

 them perfectly inoft'ensive. There would be no expense after the original 

 formation but the dra.ving of the sluices at low tide to eifeot the scour. 



"Mr. Bcek, Tower Hamlets Commission — Where I could get the fall. Hike 

 it about a quarter of an inch to 10 feet ; I think that is desirable; but there 

 are sewers where we have only the eighth of an inch fall. They act exceed- 

 ingly well. — Is that the least fall you have known .' No ; I have put a drain 

 on a dead level; that will not act quite so well, but the others do very well. 

 I put in a sewer for Mr. De Beauvoir, 3000 feet long, on a dead level, which 

 I was obliged to do from being unable to obtain a fall. That sewer has been 

 built ten years, and it has never been cleaned. — Is it subjected to any parti- 

 cular flow of water from any manufactory ? No ; it is from Hoxton New 

 Town, or De Beauvoir Town.- — Does it receive any flow of water from the 

 tide .' No. — Is there much discharge from the mouth of it ? It discharges 

 into another sewer, in Kingsland-road, belonging to the Holborn and Fins- 

 bury division. — .\re you aware whether that is the principal feeder into that 

 sewer ? I should think not. — Is there a consider.able fall in the sewer into 

 which that empties.' No ; that is nearly on a dead level also. 



Mr. Roe — What is the general fall in your sewers ; what do you consider 

 a fair fall ? I find in the regulation of the Commissioners a fall of a quarter 

 of an inch in 10 feet is required as the least fall; but we give them as much 

 fall as we can ; there are places where we cannot grt a qmrter of an inch in 

 10 feet. The outlets of our sewers are not under our own control. ^ — In that 

 case do you find the flushing effectual in a horizontal line .' Yes — You are 

 obliged to put your flushing-gates nearer .' Yes; we have a sewer building 

 on a dead level, in consequence of the difliculty of outlet ; in that case we 

 have placed a gate for IGOO feet; and we are in hopes we shall do with a 

 greater distance than tliat hereafter; but that is the greatest length we have 

 had an opportunity of working on a horizontal direction. 



Connection of Sewers and Dkains. 



With regard to the impropriety of connecting sewers at right angles 

 much evidence was given, as also with regard to the impropriety of allowing 

 drains to enter the sewers too high. Mr. Roe says, there has been an im- 

 provement in the mode of connecting one sewer with anotlier. The general 

 mode was, to connect them at right angles, or nearly so. The objections to 

 that I found to be, that there were great accumulations in the sewers ; the 

 water flowing from the collateral sewer retarded the column of water in the 

 main sewer, and thus caused an obstruction by which the filth and deposit 

 which would otherwise have passed off into the main drain, was retarded and 

 accumulated at that point and above it. The theoretic explanation of this is 

 given by Professor Butler Williams. Mr. Kelsey, of the City Commission ex- 

 presses a decided concurrence in the same views. Professor Donaldson stales 

 that his sewers are brought into contact with the main sewers either by cants 

 or by circles. 



Dr.iins. 



This subject was much discussed, and it was the decided feeling of the 

 Commission of Enquiry that the system of drains enforced by the Commis- 

 sioners of Sewers was unnecessary and oppressive. 



Mr. Biers — Being a sewer builder to a very large extent, I have often per- 

 sons to deal with who contrive to obtain a surreptitious drainage. To avoid 

 the present charges, which I admit to be exceedingly heavy, and often much 

 too large, especially for the poorer class of houses, the will sometimes give a 

 neighbour, who has paid, a trifle to permit a communication through his 

 drain ; and they will often do without a drain at all. All rated houses pay 

 to the sewer rate, whether drained or not, but the building the sewer is a 

 distinct and separate charge upon the building. I have at least 1000/. laid 

 out in sewers, of which 1 dare say I shall never see a quarter, in consequence 

 of this surreptitious mode of getting a drainage. I can mention one case 

 that lately occurred where a person had for thirteen years drained three 

 houses through one drain, having only paid for one house ; he was found out, 

 and then paid me for the other two. In another instance the cost of a sewer 

 built abutting upon the front and flank of a house amounted to nearly the 

 value of the house itself (it being one of the smaller description of buildings). 

 For this sewer I have never been paid, nor do I suppose I ever shall be. The 

 sewers are in a number of places much larger than necessary. There should 

 be a smaller sized sewer for the poorer description of houses, which would 

 be suflicient for the upper drainage, where the sewer would not be further 



extended. I built in the Edgeware-road five houses, the sewage of which 

 cost me very nearly 500/. This extravagant sized sewer is entered by an 18 

 inch barrel-drain, through which upwards of forty houses have been drained 

 for the last twenty years, and there has never been any stoppage of the least 

 importance. I had reason to expect that if this large sewer was built I 

 should be repaid a moiety of the expense ; but after the sewer was built the 

 Commissioners found that they could not compel the owners on the opposite 

 side to break up their old drainage and adopt the new ; so there the sewer 

 now remains, either as a charge upon the houses, or a loss to myself. If the 

 smaller description of drain was to drain the roadway, and the houses on 

 each side of the roadway, half the area of the present Westminster small 

 sewer would be suflicient. 



Y'ou would say that an 18-inch barrel-drain would he sufficient for 40 or 

 50 houses ? Yes, it would be quite suflicient for 200 or 300 yards in the 

 upper part of a line of sewer. That 18-inch barrel-drain has a very good 

 fall, perhaps an inch and a half to 10 feet, and in places perhaps more than 

 that. — What is the least fall which you would consider necessary for an cfli- 

 cient drainage .' I have put sewage. in at as slight a current as half an inch 

 to 10 feet, were the depth of digging was such that it could not be more. 



What is the average expense of constructing sewers of the largest descrip- 

 tion mentioned by you ? About a guinea a lineal foot ; a little more or less, 

 according to the depth of digging, &c. The second class is two or three 

 shillings per foot less. The third class somewhere about 10s. ; or less evca 

 than that. 



Mr. Roe — Can you state the length of any court which has been drained 

 by an 18-inch barrel drain ? The longest length I know is about ICO feet. — Do 

 you think it would require to be of a larger size, if it was carried farther ? 

 That would entirely depend upon the fall which might he given, and also the 

 supply of water. — Suppose you had a good fall, and a suflicient supply of 

 water, what length of court do you think could be drained by an 18-incli 

 drain.' I know one instance where an 18-inch drain is carried 400 feet at 

 the back of about 40 houses, where there is a good supply of water, and it is 

 kept clean. 



Mr. Stevens — There is a lower class of buildings — cottages — where thes^ 

 expenses are proportionately more heavy. Take, for instance, labourers' 

 houses, built to let at rents averaging 4s. a-week each ; the expense of a 

 sewer of the second class would amount to about 6/. a house. The builders 

 of such houses have not generally the means themselves; they get credit for 

 the materials, and pay interest for them ; and as soon as the houses are built 

 and let, raise money upon them. This is the way in which laige numbers of 

 small houses are built, mostly by persons who look after their own properly, 

 and ultimately they fall into the hands of builders, or persons speculating in 

 housijs. of this class. There are a great number of such persons, and to them 

 the t' .ise of sewage is of most serious coiiseqnence. The result is, they 

 omit ! 'together. The expense of the sewer to each of these houses would 

 be abo..t 6/.: the cost of the house itself not more than 50/. To defray the 

 cost of sewer, and pay the interest upon it by an annual charge, spread over 

 a period of 30 years, 7s. a year would not be felt on a rental, and would be 

 amply sufficient ; but an additional sum of 240/., added to the cost of build- 

 ing at the outset, prevents the builder adopting sewage at all, and he will 

 make a cesspool in a cellar, or adopt some other suijstitute. 



Mr. Dowley — The Westminster Commission of Sewers, as usual, got roughly 

 handled. What is the reason you have not adopted practically a smaller scale 

 of barrel drain, one of two feci, or 18 inches for some small streets of alleys .' 

 It has been considered that it would be a very dangerous precedent to go on ; 

 we should have applications from every other street in the neighbourhood to 

 do the like, and it is a dangerous thing ; we shouhl never get regular good 

 sewers built, and it is very difticult to tell when we begin a sewer how far it 

 will ultimately extend. — You think it would be objectionable as introducing 

 a bad precedent.' Y''es. — If it was found useful, it would not be introducing 

 a liad precedent ? No, probably not. — You think it might work well for the 

 smaller kind of houses ? Y'es, I think possibly it might. — Then that smaller 

 class of drain being made cheaper, would allow the landlord to charge less 

 to the poor tenant .' Y'es. 



Mr. Drew, Surrey and Kent Commission — Do you think that even an 18- 

 inch barrel-drain carried up a small street may frequently be suflScient .' Yes. 

 — That v/ould be a great deal cheaper than one of those large drains now 

 used .' Much cheaper. 



The Tower Hamlets Commission also thought small drains might be ad- 

 vantageously used in miuur streets and courts. In the City the plan has been 

 adopted of making the Sewers at the expense of the Commission, without 

 contributions from private parties, and only charging for the drains, which 

 were also made by the Commission. This new plan seems to have answered 

 well. It appears to be the strong impression of the Committee of Inquiry 

 that the drains should he carried up to the houses by the Commissioners of 

 Sewers, but on a less oppressive system. The objection of some surveyors to 

 small drains arises from the fact that they occasionally get clogged by the 

 miscliievous propensities of the lower classes, 



Mr. Bratt, a large holder of small houses, says, Some of the inconvenience 

 I have experienced is that where I have been willing to lay a drain for a con- 

 siderable length, I have met with refusal, and been told that it must be a 

 second-sized sewer. — What size wei'c you willing to have laid ? In the case 

 I especially allude to, I would have laid an 18-ineh barrel drain.- — For hoiv 

 many houses ? For one. — Were you prevented from so doing by some regu- 

 lation of the Commission ? Yes, I was compelled to pay a sum of upwards of 

 60/. to the Commissioner of Sewers for laying down a sewer. — Does the fact 



