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THE FLOODS AND PUBLIC HEALTH.

(FROM OUR SPECIAL SANITARY COMMISSIONER.)

THE floods affecting, not only the Thames valley, butmany other parts of the country will tax the resourcefulnessof our sanitary authorities to the utmost. The dampnesscaused by the water that invades dwelling houses is, ofcourse, unwholesome ; but the specific contamination due tothe filth floating in the water may be more dangerous. In

spite of great sanitary progress, no system of drainage hasbeen devised that can protect dwellings from sewage if thefloods reach a sufficiently high level. The water in thesewers, of course, can only carry the sewage away when theoutfall is at a lower level than the sewers, save wherethe conditions warrant elaborate pumping or exhaustionschemes. On the water rising at the outfall it penetrates thesewers, and the first thing that happens is the forcing backof a large volume of sewer air. If the sewers are not wellventilated at frequent intervals the sewer air pressed back-wards by the rising flood will break the seal of the domesticdrains and invade the dwelling-rooms of the houses.The actual toxicity of sewer air is not now in question-anyhow, no one wants it in the house. If the water riseshigher still the sewage itself overflows from the street andyard gullies or sewer mouths. If there are closets in thebasement of the houses the sewage will come out of theminto the house. If the closets in the house are above thelevel reached by the flood there will of course be no overflowfrom the closet; but the lower portions of the soil pipe con-necting with the sewer in the street may not be strongenough to resist the unusual pressure. The drain pipe maythen burst, and then the sewage may be distributed alikeupon the streets and inside the houses.

The Floods and the Sewage Disposal Works.Even where the flood is not so extensive as to produce an

extreme effect it is very likely to invade the sewage disposalworks, for these must be at a very low level, and this meansfrequently proximity to a water course. This is not a matterwhich need unduly frighten us. It has been calculated thatthe sewage from a total population of one and a quartermillion people, living in the Thames valley, ultimatelyreaches the Thames above the intake of the London water-supply. Yet few, if any, cities enjoy o pure and safe awater-supply as London. The sewage in the Thames valleyis carefully treated and purified before it is allowed to flowinto the Thames, while the London water-supply is keptsafe by the efficient methods of storage and filtrationemployed.The chief concern in London, of course, is the protection

of the water-supply from the floods. In 1894, after severenoois, there was a considerable amount of typhoid fever inLondon. But since that date the water-supply, especiallythe storage of the water, has been greatly improved. Thewater reservoirs are now of such vast dimensions that thewater may remain standing for a very long time before it isdrawn off for use. This prolonged settling process, apartfrom filtering, greatly facilitates purification. There is noreason to fear in London that the flood waters willbe mixed with the drinking water. The storage isso enormous that the intake of Thames water can

be stopped for a while. London is drinking Thameswater now which was collected before the floods. It isto be hoped the stored supply is sufficient to meet allwants till the floods are over, but the rainfall has beena very exceptional one and the floods have prevailedfor some time. When the great reservoir was built at Stainescomplaints were made that its embankments were so

lofty that they blocked out the view and spoilt thescenery of the surrounding country. Now that thefloods are carrying away the contents of privies, and

distributing broadcast the filth from neighbouringsewage works, we may be thankful that these embank-ments are too lofty for the floods to flow over

them and contaminate the store of drinking water forLondon. ;

When a flood invades sewage works it swamps the filter-beds and scatters the untreated sewage in all directions. After the floods have subsided the neighbouring fields are

found to be covered with a thick and odoriferous layer ofsewage sludge. The whole system of sewage disposal hasbecome inoperative, and the only hope is that the immensevolume of water produced by the flood will suffice to purifythe foul matter it carries away. In the swollen river, instreets that have become small rivers, there may be Acurrent, and a sufficiently rapid current, to wash awaydecomposing matter. But inside a house, confined withinthe four walls of a basement or a cellar, there is no current.The water stagnates and deposits filth on the walls and floorsas it gradually subsides.

The Contamination of Dwellings by Floods.In many flooded districts, especially among rural popula-

tions, there are no sewers. Even in comparatively largeprovincial places it will often be found that the water-carriage system is only applied to the more favouredparts of the town. There are still provincial towns of somesize where, as well as water-closets, there are cesspools,privy middens, or pails. The cesspools are emptied by night-soil men once a year or oftener, while the pails are generallyremoved once a week. When a flood occurs in such a placethe soil, of course, mixes with the water and floats awayfrom the pails or privies, is carried all over the inundateddistrict, into the houses, and into the wells. Thus, waterand dwellings are contaminated. All these risks are nowwith us over a large area, and in some districts are aggravatedby the large number of camps for the training of the Terri-torials and other troops. We know how severe the floods havebeen at Salisbury. It is to be hoped that the latrinesfor the soldiers encamped in the neighbourhood are con-structed according to the most approved principles; but,even so, no system has been invented that will prevent %flood lifting out the contents of a latrine and scattering itabout. A reasonable step would be to remove the camp to adistrict out of reach of the flood-a very practical object-lesson in military training, for when the enemy discoversthe right range their shells come more rapidly than a flood.Then there is other dangerous matter besides the contents ofsewers or cesspits. Apart from waste products coming fromyards where skins are tanned, tripe prepared, offal dealtwith, and many other unpleasant and unwholesome indus-tries carried on, there is the vast accumulation of householdrefuse, the contents of our dust-bins. That, again, isscattered in all directions and brought inside our houses bythe invading floods.

Remedial ffeasures,

From all this there results the obvious necessity ofapplying very prompt and vigorous measures for cleansingand disinfecting the portions of the houses that have beensubmerged. This, indeed, must be extended to all parts ofthe buildings where the damp has extended, even though itmay be some distance above the highest water level. To

give time for this to be properly done, it is fortunate if thewaters subside gradually, as all the dwellings cannot betreated at one and the same moment. When the floods-are beginning to go down, disinfectants, notably chlorinatedlime, in suitable quantities should be thrown into thewater that remains in the basements or cellars. Thereit should mix with the sludge or mud deposited by thewater on the walls and on the floor. The mud should bepiled up in some open space and sprinkled over with adisinfectant. The walls, floor, and ceiling of flooded roomsor cellars will require very careful washing and scrubbing, andfinally should be thoroughly whitewashed. A flood providesan excellent opportunity for a general clearing. Rubbish andlumber that may have accumulated during years in cellars orunder staircases and basements is rarely worth saving, and .

can now be very advantageously destroyed, burnt if possible.Bedding, if it has been soaked in suspect water, should not,be spared unless it be of such very good quality as to warrantincurring the expense of thorough disinfection. Such cleaningwork requires strict supervision. It is questionable whetherall the sanitary authorities concerned have at their disposalnumerous staffs to ensure that efficient measures will betaken. This is an occasion when the county medicalofficers of health may have to exercise their right of

supervision over the smaller district sanitary authorities.The cleansing of flooded houses must be well done-

everywhere, and not strictly enforced in one localityand neglected in another.