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but what does thus overflow I think comes up to the standard of purity of the Rivers Pollution Commissioners, being almost wholly rain water. Of course I am not concerned to defend the design of the tramway, but at the same time, in justice to the engineers, who are not present, and with whom I perhaps ought to have communicated, I may say I consider the point Mr. Jerram has alluded to does not indicate any radical error in that particular part of the permanent way, but is due simply to using one course of wood paving on either side of the rails. Mr. Jerram did not point to any sinking of the entire rail, but simply spoke of the wearing of the wood paving alongside the rails. That I am not surprised at. I knew from the first that the wood paving would not stand, and I believe it is contemplated by the engineer of the company to substitute some other material, I think scoriæ bricks : wood and granite side by side cannot possibly wear equally. Mr. Lemon complimented me on my adherence to the original estimates for the works. It so happens that I have been very much abused in Oxford for exceeding the estimates for the works; but I have never taken the trouble to defend myself. Since Mr. Lemon has raised the question, I am bound to say the works have been completed within about ten per cent of the estimate, although many things were included which I did not know of in the first instance, and which it was consequently impossible to estimate for. The cost of the purchase of land, compensation and legal expenses, I expressly left out of my estimate; and as you will have seen, from the figures given in my paper, these came to a considerable sum. On the whole Mr. Lemon's remark is perfectly fair.
Mr. LEMON: I remember you were told, by some obnoxious ratepayers, when you designed the works, that they would cost double your estimate.
The PRESIDENT: The actual cost of the works estimated for was about 102,0001., and the estimate was something over 90,0001. Of course, there were some alterations and additions made by the Board, after the estimate was prepared. With regard to the condition of the sewage farm, I certainly do not hold it up as a model sewage farm, by any means. I devoted a good deal of time and thought to the laying out of the land and distribution of the sewage, and these arrangements, I think, work fairly well. But with regard to the condition of the land, I do not feel particularly proud respecting it: I think the farm committee themselves feel that the land might be in much better condition. It is
very natural, of course, that they should wish to keep down the expenses of labour. So far as a committee can manage a farm, they no doubt have managed it very well; but that a little more labour on the filter beds would be very advantageously expended. Mr. Pritchard hits out very hard indeed at local boards managing sewage farms. Probably he is right in the main, but I can only say that the local board of Oxford would have been delighted to let their sewage farm at a very moderate rent, and they would do so now, if they could only get a reasonable figure. The most simple way for everybody would be to let sewage farms, but I fear that many other local boards are in the same position, and cannot find tenants. As to the compensation given to me, I certainly have not had 5 per cent. on the outlay. I have been paid my salary ; more than that I cannot say. However, I do not wish to refer to that any more. Mr. Hall suggested depositing tanks, and that the disposal of the sewage sludge on the land might have been an advantage. I did think of doing something of the kind, but I was led to start the farm without doing it, and up to the present time I have not seen any real reason to incur the expense and the nuisance of having to deal with the sludge. The only fault of dealing with the raw sewage is, that when a filter bed has been working continuously several days, a thin crust forms on it, which, however, dries rapidly and disperses, and in a few days after the sewage has been off, disappears entirely; therefore up to the present time I have not felt the necessity of depositing tanks. I am not sure I understood Mr. Hall's remark about using the deposit to raise the level of the ground.
Mr. JAMES HALL: I understood you had to bring more soil to raise the level of the surface of one portion of the ground.
The PRESIDENT: Yes, 13,000 cubic yards of earth have been deposited at the pumping station. Part came from the foundations of the engine-house and other buildings, but the great bulk was dredged from the river close by, and I could not possibly have got it cheaper than that. I do not know that I differ much from Mr. Hall as to steam power for traction on tramways; but I fear any attempt to introduce steam power into Oxford would be looked upon even as a greater offence than the widening of Magdalen bridge, if that were possible. More than that I cannot say. It would be such a violation of the peaceful and classical associations of Oxford, that the man who was bold enough to suggest such a thing would get very short grace. Mr. Parker went into the financial question rather deeper than I was able to follow him. I am afraid I cannot give him the information he wants. We have no borough accountant, but the accounts are kept partly by the clerk, and partly by myself; it is therefore very difficult to give detailed information on any financial point raised suddenly. The effect of the whole scheme of drainage and irrigation works has been about a 18. 1d. rate in the year. That covers everything. Reference was made by Mr. Parker and another speaker to a penny rate, but I understood him, a penny rate in aid of a sewage farm.
Mr. JAMES HALL: I said a penny rate in aid.
The PRESIDENT: We have no rate in aid, and we really saved 4501. in the first year, under very adverse circumstances, but which was lost in the second by an outbreak of foot and mouth disease. Agriculture has been very much depressed, and this land came to us in a very bad condition. It was known that it was coming to us and it was consequently neglected, and a portion of it could not be cropped the first year. I am sorry Dr. Acland has gone, because I think he was entitled to a word of thanks. I am sorry he was not able to be present last night. One of our honorary Members, Mr. John Thornhill Harrison, would have been present, had he not had a Government Enquiry fixed beforehand for today near to Newcastle. It will be gratifying to Members to know the interest taken in our Association by one of the Inspectors of the Local Government Board. I can only in conclusion thank you for your graceful criticism passed on my work, and for the courtesy and kindness exhibited to me generally.
THE SEPARATE SYSTEM OF SEWERAGE AS
CARRIED OUT AT READING.
BY ALBERT W. PARRY, Assoc. M. INST. C.E., BOROUGH
As many references have been made to the separate system of sewerage in Reading, I have endeavoured to put together, for the information of the Members of the Association, as much practical detail as I believe will fairly illustrate the system as it is or shortly will be in operation.
The system cannot be taken as a complete one so far as surface water is concerned, as all the sewers are not new. A system of sewers for the disposal and utilisation of sewage was completed about seven years ago, and the old sewers, which formerly conveyed · both sewage and surface water, are now used only for surface water, and in streets where there were no such sewers, new ones are
The urgent need for keeping the rain water out of the main sewers has been experienced during heavy rains and floods, when surface water in large quantity found its way into the sewers, which so increased by dilution the quantity of sewage, that great inconvenience has been caused by the volume that had to be pumped and received on to the farm at a time when it was least wanted.
Reading certainly made a mistake in not dealing with and providing means for the completion of the double system of sewers in their Act obtained in 1870, which provided only for the disposal of the sewage, and not for the completion of the sewers for surface water, which has had to be undertaken under powers obtained by a special Act for general purposes in 1881. The consequence has been that the drainage of sewage from houses has been completed to a large extent without regard to the disposal of rain water, and the carrying out of powers obtained under the Reading Corporation Act, 1881, necessitated a second opening of streets where new surface-water sewers and branch drains were required, and some amount of irritation is caused to owners of properties who had, as they thought, completed their drainage, and who now have to make additional drains at a second expense.
The disposal and utilisation of sewage in Reading has already been described by me in a former paper, but for present convenience I will again briefly epitomise the system.
The works were designed by Messrs. Lawson and Mansergh, of Westminster, and were executed under their direction.
Reading is divided into three principal districts by the river Kennet and the ridge traversed by the Bath road. The districts are drained by separate main sewers, which discharge into a 6-foot barrel sewer.
The main receiving sewer has been constructed of a large size in order to act as a reservoir with the view to regulate the pumping.
Great precautions were taken to prevent leakage into the sewers, and for this purpose all the brick sewers were rendered and made water-tight.
Ordinary sewer pipes were used, and the joints, except in a few cases at the commencement of the work, were made with cement. Many of these pipe sewers are laid 3 or 4 feet under water, and in the Caversham road, in soft silty foundations.
The leakages that occurred before the commencement of the house drainage works, no doubt entered the sewers by means of the clay-stoppered junctions, and was estimated by the resident engineer to amount to about 3 gallons per head in the winter, and 2 gallons in the summer.
Duplicate engine power is provided at the pumping station, because during a part of the year the Thames floods render the water-pumping power useless.
There are two horizontal condensing engines with 24-inch cylinders and 3 feet 6 inches stroke, with three boilers 28 feet long and 7 feet in diameter. The engine pumps are 30 inches diameter and 3 feet stroke, and work at the rate of 14 strokes per minute. There are three turbines for ordinary pumping purposes. The turbine pumps are 18 inches diameter and 2 feet 6 inches stroke, which work 154 strokes per minute.
To provide for the possible contingency of a breakdown, or a rupture in the rising main, an overflow into the river has been provided
The sewage is pumped to a height of 46 feet, the rising main being 4711 feet long and 24 inches diameter. It then enters a culvert 3 feet in diameter, in which it flows by gravitation for a length of 8192 feet to the sewage farm.
The farm consists of 700 acres lying to the south-west of the