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strikes one is the absence of any clause governing the submission of correct plans and sections. Is this fair to the local authorities' surveyors ? How can drainage be properly supervised or the system be approved by the authority if no plans have to be submitted ? Granted that perhaps twenty-five per cent. of architects would send in a drainage plan, the fact remains that in the more strictly suburban districts of London a large number of builders dispense with the services of architects entirely, and are then only too thankful to be relieved of the necessity of submitting plans. There is little doubt, if this is not made compulsory, it will to some extent retard the beneficial results that might be expected from other by-laws.
Another omission that demands attention is the submission of notices, one giving date of commencement and one giving date of completion or when ready for testing, since this gives the builder but little trouble while on the other hand it forms a record for reference, and should the work be defective and action before a magistrate become necessary, the notice signed by the builder is sufficient evidence that the work was presumably complete and would have been covered in had no action been taken. The author has found these notices extremely useful in the course of supervising several hundred systems of domestic drainage.
It would be advantageous if all plans were drawn to a similar scale, and upon forms supplied by the local authority; these should have all particulars, such as quality of materials, gradients, position of closets, sinks, baths, lavatories, inspection chambers, gullies, and disconnecting traps shown on, together with figured dimensions where necessary, and the proposed date of commencement and completion, with the name and address
of the builder, owner, and occupier. They would then form a complete record for future reference. A duplicate signed copy would also be of great assistance to those supervising the work if one could be kept upon the building while the work was in progress.
There seems to be no mention of approval of plans, since they are not required, but if a by-law is framed to make this necessary, there should also be one providing for the approval of the authority before commencement of work; at the same time this approval should be given within a limited time after submission of correct plans, since it would be unfair to keep important work waiting for a considerable time. It should also enforce carrying out the work in accordance with the drawings approved, as it is no uncommon occurrence in speculative work for the builder to submit a drainage plan, and, after it has been approved, to carry out the work as he prefers it, with no thought as to the socalled correct record held by the local authority.
To return to the draft.
By-law 1 provides that no subsoil drain shall communicate directly with a sewer, but that a suitable and efficient trap shall be provided, with a ventilating opening at a point in the subsoil drain as near as practicable to such trap. This by-law seems to imply that a subsoil drain, where it is necessary to lay one, may connect directly with the house drain, as this would provide the trap and ventilator, in accordance with the requirements of subsequent by-laws, before connecting with a sewer.
In my opinion the subsoil drain should, wherever possible, connect to the house drain above the sewer disconnecting trap, but not without an additional trap and ventilator, which prevents any contaminated air entering the subsoil drain in ordinary weather, while in excessively dry weather should the one trap become unsealed by evaporation the sewer is still disconnected. In every case all pipes beyond the subsoil trap should be laid and jointed as for a sewage drain.
By-law 2 provides that all rain-water pipes shall discharge over trapped gullies, or into such gullies above the water in the trap. It also precludes utilising this pipe as a means of carrying waste water from baths, sinks, lavatories, &c., to the drain. The first part of this by-law is good, though for water it is often considered better to discharge over a channel leading to a trapped gully 12 or 18 inches distant from the wall. This is advantageous for two reasons: (A) to prevent any foul air rising up the pipe if the trap should be forced; and (B) to prevent the risk of soakage into foundations. In practice, however, this method is difficult to carry out where the space is limited. With regard to the second part, it appears rather arbitrary to keep the rain water entirely separate from baths, &c. Undoubtedly slopsinks should be treated as closets, and sinks which receive grease or liquid refuse kept separate; but there seems little objection to the same rain-water head taking a bath or lavatory waste as well as a rain-water pipe; in fact it is even advantageous, since in dry weather rainwater gullies often become unsealed by evaporation, while baths and lavatories in daily use would prevent this risk.
The absence of any direct obligation to provide metal rain-water gutters to all roofs, including porches, baywindows, &c., seems peculiar, as the omission of these will prove a source of dampness to the walls as well as of injury to the foundations.
Another matter which needs attention is the provision of means for taking away surface waters from yards or paved areas, and the prohibition of the use of the public pavement for the purpose of carrying rain water from front roofs to the street gutters, as in frosty weather this is a constant source of danger to pedestrians.
By-law 3 provides for drains (other than subsoil) to be of glazed stoneware, semi-vitrified ware, cast-iron, or other equally suitable material, for means of access to and sizes of drains, for jointing, trapping of inlets, and concrete round pipes. There seems nothing unusual in these provisions, except that the thickness of stoneware pipes might be mentioned, and the jointing and gradients specified more in detail. Cement is undoubtedly the correct material for jointing socketed stoneware or other similar pipes, but in a model code of by-laws this simple statement seems insufficient. Should not some standard quality or test for cement be required, and the use of gastim made compulsory? Where gastim is used there is but little difficulty in obtaining efficient joints, while the quality of cement is most essential. Upon opening up a system of drainage to a country house which had been laid about a year, and at time of laying satisfactorily stood the water test, I found over 75 per cent. of the collars of the stoneware pipes burst off, owing to the cement being hot, and not air-slaked or killed previous to use.
The jointing of iron pipes should be made with gastim and lead run in and well caulked. The bed of good concrete is ambiguous since no width is stated, for a bed of concrete 2 or 3 inches wide and 6 inches deep would be absurd as well as useless. What seems to be required is the concrete brought up to at least the level of half the pipe embedded in it, and of sufficient width to give lateral support. Where a drain adjoins a heavy wall and is below the foundation, benchings of solid concrete should be provided or the timbering left in to prevent settlement, as this will repeatedly occur if these precautions are not taken.
There is no minimum or definite gradient specified, as perhaps it might be found unnecessarily severe, but where the fall is not self-cleansing I think automatic flushing tanks should be made compulsory. The head of water (2 feet) specified for testing purposes is ample, but will this be obtained ? It will be found difficult in many cases where there are a number of branch connections, manholes and gullies, especially as the onus of preparing for and charging the drains with water appears to be neither upon the builder nor the local authority. Unless this is made the subject of a by-law, it will be impossible to compel a builder to charge the drains he is constructing, and if he once realises this it will mean trouble and expense to every local authority.
. Where a drain passes under a building it must be laid in a direct line, and encased in 6 inches of Portland cement concrete if of stoneware, but iron drains are exempted from this latter requirement. In every case ventilation must be provided at each end of that portion under the house, but drains are only to be allowed under buildings where any other method is impracticable. The old-fashioned D traps, bell traps, and dip traps are not to be used.
By-law 4 deals with the intercepting trap and inspection chamber. It seems a pity that the “suitable trap” is still required, but if it must be used might it not be advantageous to commence a new era of sewer ventilation by providing for a high vertical shaft from the sewer side of the trap? The method of building and materials for inspection chamber should be clearly stated in detail, since instead of good cement brickwork