Show contamination OF FARM WATER SUPPLY 1 aare r 0 VA eriq L 0 J HIP 1 0 R rop VIEW cistern filter of concrete and stone many diseases may bo be transmitted by means of water and some soine of tho the diseases are so uniformly transmitted by this means mean that thoy they aro are known as water borno diseases typhoid dysentery and other intestinal como come under this class of and consequently it la IH of tile tho greatest importance por tunce that overy every precaution bo be taken to insure IL a pure water supply says bays bulletin no 57 7 of tho the united states department of agriculture farm water supplies llos may be ba divided into three elastics classes in the order ot of their liability to pollution these are surface supplies shallow underground supplies and deep underground supplies tho the surface supplies aro are ob from streams ponds reservoirs and cisterns both shallow and feel deep underground supplies apo obtained from dug bored driven or drilled wells and from springs the investigations of K N F kellerman nan and 11 II A faker of the dopart department of agriculture in operation cooperation co with tho the Alinne minnesota sota state board of health I 1 indicate that of 79 carefully select edar ar I 1 typical water supplies in minnesota 20 wore good and 59 were polluted of tile polluted wella 11 were so located that oven extreme caro care would not mako make them safe 10 were poorly located but Improve improvements mon s la in we prote protection dilon from surface wash and would make them safe 25 were bad only because of poor cur curdice fice protection anil and could easily bo be mado made safe practically all tho the pur surface face supplies investigated were polluted curing those investigations flohil 23 of tho farms examined showed a record ot of typhoid fever surface water supplies are ara those most moat 11 liable to pollution and ties agree agree that they aro the most un j y for farm uee streams A q typed of deep and shall ov wells and ponds receive the greater part of tho the surface wash baah immediato immediate neighborhood and in man y cases barnyard or stockyard drainage from points remote from from whore where tile tho water is taken tor for household ilse aae trama or ponds dodds located in iLLi itu fields or whore stock can g gain alfi access to them ara are polluted sometimes sewage and house drainage are emptied into streams had and ponds in fact since they aro are open and gnp unprotected protected thira aro are a thousand and one dir different terent sources of p pollution ol lution rain waters from the root roof are polluted by dust dirt and leaves which collect la tho eave trough and by the drop droppings pinks fram tro m birds surface water supplies should here fore oro not bo be used for household pur pup posos poses unless forcash tor for wash I 1 band milk cans cana or for or laundry purposes and it may bo be safely assumed that th atthe the person who Kho drinks water ater from supplies ek eu dangers hie bis health it if such supplies aro are not first protected from tho the sources of contamination na as far na as possible and then purified in localities where underground waters aro arn hard bard to obtain cisterns may be used tor for the Alt filtration ration partial purl purification fi and nd sor storage arge of rain water tho the size alzo of the ohp cistern depend ou the number of bf persons jn tho bouso lapso and nd on an the general water consumption the cistern should bo be of watertight water tight construction tu to prevent leakage and to td prevent po pollution lution froin tho the boring soil it ih should havo have an overflow drain and a tight ca cover vor thero should also be sr table provision for straining or or tho the water our to its entrance trance to the cistern concrete la ii probably iha tary and durable material tor r cisterns la the walls walle and hoor should bo be 6 to 8 inches thick and well reinforced and the concrete should be bd carefully proportioned find and mixed A mixture of I 1 aart cement to 2 or 2 parts of 0 clean cean I 1 sharp sand band and 4 or 5 parts of clean and fairly small crushed rock or gravel la ie r faiell watertight concrete the leslae surface chouk be coated with AI to lo 2 ee cement m edt tu lu MI tho tha nipe cipe cam them empty into a r ceiling liter filter made of c con on croto crote which contains fine sand gravel and powdered charcoal in layers aud and from which it empties 1 into ts tho the cistern cla tern tho the rainwater rain water pipe from tho the eave should bo be provided with a switch or cutoff cut off so that tho the flow may bo be blvd diverted rt to the outside as an for instance for a time at the beginning of rains to exclude the filth collected on the root roof and gutters an overflow pipe should bo be provided in tile the bilde filde of 0 tho the cistern and should bo be screened to exclude rats and other vermin it Is usual to distinguish between Bli shallow allow underground supplies and deep underground supplies wells from 15 to 30 feet in depth to water flowing in a layer of gravel or mud which rests on oh an Imper impervious s et stratum ratum anre considered as aa sources of shallow underground supply iloth both bli allow and doop deep farm wells are often polluted from local sources they aio are often located for convenience in the barnyard under the stable or barn close to stock pens privy vaults or leaching or close to the back door out ot which household slope are thrown and near which animal an and vegetable refuse Is often al lowed to accumulate and decompose tile tho soil boll sui surrounding rounding tho well becomes saiu saturated rated with organic filth and un ablo able finally to perform its ita useful work of filtration and purification allows tile the surface water ater percolating abing through it to carry its load of contamination into tile the well may be localos ht at such gunj f a distance distan co from sources of contamination 1 ahat that oral ordinary nary pumping will bring no bad resli results ltd bawin As or eo unusually heavy pumping tho unde underground i reground water surfaced ej for a a distance around ilia alio wt well I 1 may bo be lowered to reach tho the zone of contamination deep bored or driven wells wella are less liable to pollution than shallow dug or b cred wells walls the safety of water supplies when near sour sources cew of possible surf aur taco aci gollu tion often ofte n dej Biond 1610 bo cliar actor acter and quality of tho the material la in which the well la is sunk surface waters in sinking through sandy solla soils a 0 surfaces Bur faces aro are filtered anden aud ln the finer sands much af pf of the polluting matter which they carry la Is frequently removed in coarser sands sandi or gravel the degree of filtration la Is loss but water taken from sands and gravels at a considerable depth may be ba considered sate safe waters from wells la in clayware clay sare Lre not often polluted since surface pollution niters filters clay very water from wells wella in are frequently polluted owl ovong n i g to the fact that chat hm estone nalle abila usually c contain eatn passages and channels chan neja at different depths which a continuous passage for wa j d ter for a cotia an and which die are meryi ery often birb annec ed with strike and hero herd and there on alib it la is a common practise to dulip manure 7 trash and garbage gar bafia into uch such sinks or or basins and rain water falling into these friese jil plunges i didies directly into the underground channels carrying with it the irom from the basan to 6 those points whore where wells are sunk in this mannet manner garbage or refuse e dumped anywhere in tho beig neighborhood or ean a ata a from a well in limestone may pollute the tha water rater |