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inadequate carrying capacity of the existing mains, which may be of too small diameter or perhaps corroded. In many burghs and villages post-war building schemes have necessitated an extension of sewers and water mains and an increased demand on the water supply, which in some areas is no more than sufficient for existing demands. To overcome these obstacles would require the execution of work which, at existing prices of material and labour, would involve a greater increase in the rates than the local authorities are willing to impose. In some of the smaller burghs and villages conditions are far from ideal, but the financial problem is proving an insurmountable difficulty in carrying out the necessary improvement.

2. Water Supply.—The following are some typical examples that have come under observation :

(a) A small burgh of 1,300 inhabitants in the south-west of Scotland is dependent for its water supply on a number of shallow wells. Chemical and bacteriological analyses made from time to time have shewn the water to be of doubtful purity, and since 1883 the problem of providing an adequate and satisfactory water supply has remained unsolved.

In that year partly owing to local complaints and partly on account of pressure from the central department of the time (the Board of Supervision), the local authority considered the alternative of sinking additional wells or of seeking a gravitation supply. The burgh being built on a hill, a gravitation supply which would give sufficient pressure was reported at that date as being likely to entail a rate of between 2s. 6d. and 5s. in the £. In view, however, of a not unsatisfactory chemical analysis of water obtained later in the year from three of the burgh wells, nothing was done. In 1898 the local authority evolved a scheme of sinking a deep bore on a neighbouring hill, but this "at 52 feet drained the town of £70 without bringing in a gallon of water.'

In 1910 the local authority sought the advice of a water engineer, who reported on a scheme for pumping water from a number of new wells to be sunk near the town. The scheme was estimated to cost £4,450, but in view of the uncertainty of finding water when the work had been done, and of the heavy maintenance costs entailed by the pumping plant from the sixteen wells considered necessary, he did not recommend such an expedient. Several partial gravitation schemes, all involving pumping in view of the altitude of the burgh, were reported on, and the two most attractive of these were estimated to cost £5,400 and £4,800 respectively, exclusive of the expense of maintenance (which would be greater in the case of the latter scheme). These capital works would have entailed rates as follows (to be divided equally between owner and occupier) :

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In 1912 a plebiscite of the ratepayers on the question of gravitation supply v. wells was taken, and 109 ratepayers voted for the former, 219 for the latter. Early in the following year the local authority resolved" to sink sufficient wells in the immediate neighbourhood of the town to give an abundant supply of pure spring water in all parts of the town." One test well was sunk, and the analyses of water taken from it were considered not unsatisfactory. The medical officer of health, however, directed attention to the fact that the surroundings were undesirable, and that the quantity was insufficient for the needs of the burgh. The Central Department were subsequently informed that the well was not being used, and had never been used as a source of water supply for the burgh.

There matters rested during the period of the war. The question has now been re-opened, and the two gravitation schemes estimated in 1910 at £5,400 and £4,800 are now quoted at £13,000 and £12,000 respectively. The rates entailed by these capital costs would be between 4s and 5s. in the £, and the local authority have pronounced those to be beyond the financial resources of the inhabitants.

(b) A village in the south of Scotland consists of some 36 houses. This village has not been formed into a special district for water supply purposes, and the three existing gravitation supplies are owned and managed by the proprietors. It is reported that from the point of view of both quality and quantity one of the supplies is hardly satisfactory, and that the quantity from each of the other two supplies has been found barely sufficient in a dry summer. At least one proprietor has sought for a better supply, but the search has been unsuccessful.

The matter has engaged the attention of the local authority in view of their statutory duty to see that a proper supply of wholesome water is provided, and because they propose to build, with State assistance, some 30 to 40 houses. A report from a water engineer was obtained, but the capital cost of the cheapest scheme suggested by him entailed a rate of more than 13s. 6d. in the £, after taking into account the increased assessable rental due to the additional houses proposed to be built. To that rate must be added the annual charge for maintenance; and the scheme judged by modern standards would be incomplete without a drainage scheme, which would involve further considerable expenditure. These costs, the local authority felt, were beyond the resources of the community.

(c) A small community of about 50 persons on the north-west seaboard of Scotland draws its water supply from a shallow well over which sea spray is carried in stormy weather. The water is said to be in summer very dark and muddy and to have an offensive odour, and in winter to be brackish in taste. Chemical analysis has shewn the water to be free from dangerous pollution, but to have a chlorine content equivalent to 13.8 grains of salt per gallon. (The maximum salt content for a potable water may be taken as 3.5 grains per gallon.) Obviously the water is

unsuitable for washing. The nearest available supply of good water is nearly a mile away from the township across an arm of the sea and has to be transported. The distance by land is nearly two miles. The track of a gravitation supply across the sea would be difficult to lay on account of rocks and large boulders. The capital cost has been estimated at £500 (exclusive of maintenance), an expenditure which is beyond the resources of such a small community.

(d) The water supply to a small village on the shores of the Moray Firth is from three wells situated among rocks below the village. During summer the quantity of water available is very limited, and water for cattle and horses has to be drawn from other sources. On its western side the village is about a mile distant from a small burgh of 1,400 inhabitants with a gravitation water supply. That supply is, however, no more than sufficient for the present needs of the burgh, and negotiations with a view to a supply being given to the village have been unsuccessful. On its eastern side, also about a mile distant from the village, are the pipes of a special water supply district, but the reservoir is not high enough to guarantee a supply in the higher parts of the village.

Pumping apparatus with lengthy piping and storage accommodation would be required to bring the water into the village either from the existing wells or from another possible source that has been suggested, but the rate in respect of the capital cost would exceed 10s. in the £.

Local authorities have frequently applied to the Board for financial assistance towards the cost of such schemes, but there is at present no fund available for the purpose. The Royal Commission on Housing, which reported in 1918, recommended that a fund of £20,000 a year should be provided for ten years to assist local authorities in the crofting counties to improve the drainage and water supplies of crofting townships, in accordance with approved schemes. This recommendation has not been carried into effect; but in any case the fund would not have been available for burghs and villages outside the crofting counties.

Many other matters of difficulty in regard to water supply have been referred to the Board, and the services of the technical staff have frequently been given to assist and advise local authorities in matters of difficulty.

One local authority received serious complaints that the water supply contained large numbers of crustacea (gammerus pulex) and blood worms (larvæ of midges), in addition to a considerable amount of sediment. It appeared on enquiry that the crustacea were common in this water supply twenty years ago, and that for several years special measures had to be taken to get rid of them. It would appear, however, that they had been present in the pipes all the time, and although repeated scouring of the pipes has reduced their numbers, their total eradication has proved to be a difficult matter. Continued scouring is expected to remove this impurity, and investigation is being made into the question

whether treatment of the water by chlorination or some such method would not result in its total disappearance. With regard to the blood worms, it is believed that these originated at the reservoir, and although they would be caught by the filters, it is assumed that their eggs may have passed through into the supply tank. From the tank the eggs would be carried into the supply pipes and would develop there into the larval form. The abundance of the worms observed during the year can only be ascribed to abnormal climatic conditions, the approach of cold weather having caused their disappearance. Enquiry is being made as to the working of the filters with a view to remedying all cause of complaint.

3. Perth Water Supply.-During the year the Corporation of the City of Perth obtained a Provisional Order, which was duly confirmed by Parliament, to obtain a supply of water from the River Tay. This is the third Water Provisional Order that the Corporation has promoted since the War.

The present supply is obtained from the River Tay at Moncrieff Island and Victoria Bridge. The water is taken from the river by soakage through the natural gravel of the river-bed into filters constructed below the river. Filters were first constructed there in 1830, and were extended in 1877. The water gravitates from the filters to a pumping station, and is then pumped to service reservoirs, and thence distributed to the consumers, though some houses are supplied from the rising main.

This supply is liable to gross sewage pollution, the sewage of the town being discharged in a crude state into the Tay at a point half a mile below Moncrieff Island, and carried by rising tides well above the points of intake. It may be noted, as possibly associated with the pollution of the water supply, that in no year since 1897 (and possibly earlier) has the city been entirely free from cases of typhoid fever; and in 1906, 1913 and 1919 outbreaks of that disease assumed serious dimensions, the last being the worst.

In 1913 the Scottish Army Command informed the Local Government Board of an outbreak of epidemic diarrhoea among troops stationed at Perth. Following on the complaint then received, a careful investigation was made, and bacteriological examination of samples of water taken from the source of supply furnished evidence of considerable pollution there. The bacteriologist in a report dated 3rd January, 1914, stated that in his opinion half the water supply of Perth was so seriously contaminated with sewage as to make the whole supply of the city unfit for human consumption. Accordingly, on 12th January, 1914, the Board called upon the local authority to provide a satisfactory supply of water; and, pending consideration of the question of a new supply, requested them to take measures for the best practicable protection of the existing supply from gross pollution. The local authority then obtained reports on various schemes, but did not carry any of them into execution, and it was not till the outbreak of typhoid in 1919

that the chlorination of the present water supply was commenced.

In 1915 the local authority had before them several schemes for a gravitation water supply, and among them was a scheme with a gathering ground on the Ochil Hills draining to the River May (a tributary of the Earn), on which a reservoir was to be constructed about 12 miles south-west of Perth. This would have provided the town with an abundant and pure supply for many years to come. It was, however, considered too costly, and the scheme was abandoned.

In 1921 the local authority promoted a Provisional Order for a supply from the Tay. The scheme then proposed was known as Bertha Scheme. The proposal was to draw water from a point in the river above the confluence of the Tay and Almond and beyond tidal influence and local contamination, to pass the water through a filtering plant, and thereafter to store and distribute it. The scheme was sanctioned by Parliament in 1921, but was not carried out.

In 1925 the local authority promoted another Order to take water from Loch Ordie, about 20 miles north of Perth. This is an upland loch with pure water, although probably somewhat peaty. The water was to reach the town, and to be distributed by gravitation. This would have had the effect of doing away with the present pumping station, and all the difficulties that attend abstracting water from a river that is relatively impure. This scheme came before the Commissioners acting under the Private Legislation Procedure (Scotland) Act, 1899, and the preamble was proved; but before the Order had been confirmed by Parliament an election took place in Perth and a petition was presented by the new Town Council withdrawing the Order.

The new Town Council appointed another engineer, who now proposed to take water from the Tay at a point above Perth but below the confluence of the Tav and Almond. This is the scheme that has now been authorised by the Order confirmed by Parliament last year. The water is to be abstracted from the Tay by means of a series of conduits constructed in a gravel bank at a point opposite Woody Island and almost opposite Scone Palace. At this point the river is not entirely free from tidal influence and is liable to sewage pollution. It was accordingly, in the Board's view, desirable that adequate sterilising plant should be installed under the management and control of a qualified bacteriologist. As the Draft Provisional Order did not lay upon the Corporation the specific duty to do this, the Department, when reporting in terms of the General Orders under the Private Legislation Procedure Act, recommended the inclusion of specific provision to the effect indicated. After negotiations with the Corporation the following provisions were agreed to and incorporated in the Order (Clause 10) :—

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(1) The Corporation shall so long as any part of the water supply for the burgh is taken from the River Tay provide an adequate and efficient chlorinating plant to the

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