Show GRAVITY SEWER SCHEME the following report from expert consulting engineer aj J J crow cross was read in the City council last night I 1 have the honor to report the re of the examination I 1 have made at your request with reference to tho the most advantageous method of die posing of the sewage of salt lake lacto city and especially with reference to the plaus plans prepared by mr A p doremus city engineer for the coal con meyance of the main part ot of ane sewage by gravity in a closed conduit to it a point several miles north of tho the city where it can b bu bi i utilized for the irrigation of land in order to havo have a proper ua der stand g of the case it is nary aary to first examine the topical topic f features ot of the city and vicinity the wasatch range of mountains forms the easterly boundary line of the salt lake valley these rhese mountains rise abruptly from the plain waichi I 1 la a dead level ta leet feet above tho the sea for snout ten miles from great salt lake and then rises to the south at the rate of about two feet to we the mile for about ten miles I 1 urther further beyond win which ich it rises more rapidly through this valley nearly nearl v parallel to the mountain range and five lull miles distant from it a channel eight to ten feet deep has been out cut by the river jordan a stream fed by utah lake aud discharging into great salt lake which has no visible outlet and th the water level in which fluctuates sever severe ai loot leet in a series of years according to io the temperature suit and precipitation of snow in the mountains the annual rainfall on the lake and in the valley being only about eight eighteen eeLi luct inches left per annum about thirteen miles from the mouth of the th jordan river at red butte canyon the wasatch mountain ranke baliv 0 advances au vances sharply towards the river about three miles and this advancer advanced rang is with hot and suj pharous springs in the cove thus formed there has been created by thie the wash irom several canyons in the itte mountain range a large deposit of material creating a plateau irom from the mountain to within about a 4 mile ot 01 the river at the most advanced adva point of the hod springe mountain anti and receding a 8 atherly to a distance of r 1 two miles from the jordan in ab about aut three miles ou on this plateau Is ia situated salt lake city the city limits aid j include the bottom lands along the river bank u each side the jania ou on the east vary varying as above irom from one to two miles in id width and that on the west being almost level jor several miles and tar far beyond the city boundary the streets of the city are laid out at an anglo angle of about 45 degrees with ai the line of atthe the base of the plateau so that thag the surface drainage of all the territory above the bottom lands lando bordering the river is in toward the south and west while the ultimate disposal ot of the drainage water of all kind must be to the northward in accordance with the slope of the river and the valley it has been recognized by all those who have given the matter any afteu tion that the discharge of the sewage selvage directly dire otly into the jordan river along the city front could not be permitted to discharge it into an intercepting mower parallel top to and at the level of the river with its outlet far enough below the city to avoid creating a nuisance to is impracticable in consequence of the low elevation of the land adjoining the river and the want of sufficient slope to carry off the sewage in a pipe or sewer of practicable size in the system adopted and now partially constructed and in operation the sewage is all carried for about a mile from the highest street which runs through from the mountain to the riv erand is then conveyed through fifth south street for two miles to a well near the river bauk bank from which it is in pumped during eighteen hours houra of the day through a 12 inch pipe two miles long and discharged into a canal built to relieve the jordan during excessive fr fresh eshete ets and is carried off in that canal to be dise discharged barged in salt lake this method of disposal proves to be eX expensive and the pumping pl int which has been put in is already very much too small for the work required sixty percent per cent of the sewage which to is now delivered at the pump well has to be allowed to flow directly into the river and to pump the he remaining 40 per cent over into the surplus canal costs per annum the sewage which flows to the pump station is delivered from sixteen and a half miles of sewers affording drainage to acres acre 1 of property out of the 2000 acres which are more or less occupied by dwellings and business houses bouses above thelow the low lands adjoining the river and which ought to be all provided with sewer facilities at as an early a day as practicable in making provision at this time for disposing of the sewage from this section of the city there ought also to be included an additional area which Is IP rapidly becoming occupied by residences to the southeast of the new city hall and above the elevation ou od which it la is situated AS nearly as cark can be estimated the habitable area more than thirty feet above the river for which sewerage facilities and disposal ought to be provided to is acres there is also an area of about 2600 2500 acres east of the jordan river for which sewerage must some day be provided and another area of 2500 acres west of the river fiver which will need bewering se both ot these areas lie so low that then jig is no do possibility of disposing of the sewage except by pumping the sewage from the acres jy ayi 9 on oil the high levels can however be disposed of by gravity without pumping or other means rt inquiring quiring constant skilled labor and the question for us to consider is whether the cost of eu au h b disposal would be greater or less than the apparently simpler mode of letting the sewage flow down to the lower level and pumping it to some distant outlet outlets such ucb as the surplus canal or rendering it inoffensive and discharging it into the jordan river in considering these alternative plans for disposing of the sewage the market value of the effluent im id very important in the climate of utah water is the one commodity which makes land not only productive but simply habitable and the first thought which occurs to one on g the present method of sewage disposal in sait halt lake olty city is that the city Is expending expanding annually a large sum to throw away and render ren jer absolutely valueless a sufficient quantity of water to render productive more than acres of farm land and that too water of a superior quality qualify for irrigation purposes to any that could be procured from natural sources in the mountains being not only enriched by domestic wastes but raised in temperature in other climates where water is plentiful and the land needs other fertilizers to make it productive many efforts have been made to utilize the solid products of city sewage and permit the water to flow to waste after having been rendered au none of these efforts have proven sufficiently re to warrant their adap tion except as a sanitary necessity and it would be folly to attempt them here where the conditions which call for their trial do not exist the first point to which my attention was turned was therefore the existence of a locality to which the sewage water could be diverted with the greatest benefit and at the least expenditure pend iture and the entire territory to the west and north of the city was examined with that in view along the western front of the city between the base ot or the hill bill and aej the surplus canal a distance of threw three to five miles the ground lies so low that sewage from the hill cannot be distributed over the surface without being carried at least three miles in iron under a head and then either pumped irom from sumps bumps or allowed to rise above the surface in the latter case the conduits would be inverted siphons hons in which the flow would he be fluctuating and irregular and they would certainly be frequently clogged by the deposits from the 1110 sewage whether pumped or phoned siphoned sy there would be needed not lose less than three such conduits five miles long each capable ot of carrying off sewage at the rate of gallons in twenty four hours in case of pumping there would further have to be noi nog less than three pumps and pumping plantes MD can able of pumping a out gallons an hour to a height of twenty feet rhe annual cost of operating this pumping plant would not be less than per annum equivalent to the th interest on this if exclusive of the cost of the plant the present pumping plant owing to an insufficient size of the force main does a duty equivalent to pumping gallons an lour under a head of forty foot feet the territory on which this sewage would have to be distributed for irrigation is now in condition to be abundantly supplied with water by gravity from the upper waters of the jordan this whole scheme appeared so unwieldy complicated complicate 1 and expensive extensive that atten attention tiou was turned to the project recommended by the city engineer fur for conveying the sewage of the plateau by gravity to a tract ot ol land lying four mies mi eg north of the city fur which there Is apparently nu no supply ot of water available from mountain str streams earns all the water from the range to the eastward being already utilized on lands aire otly at the base of the mountain the very thorough surveys made by the city engineer show that is ic will be I 1 practicable to intercept all the BO wage sewage flowing from the city above a plane thirty feet above the jordan and convey don it by a conduit of a total tatal length of seven miles to the surface of the tract above mentioned which lies between the foothills foot hills bills and the jordan has a toil roil suitable for immediate production of crops if moisture is supplied and extends with a gentle slope several miles go co the northward I 1 have carefully examined the line lime and profile proposed for this conduit by the city engineer and am of the opinion that its construction presents pre sento the most moot feasible and economical method of disposing of the present sud aud future sewage of so much of salt lake city as lies above a line beginning at liberty park on the curving around past the now new city hall the union pacific railroad depot and the deseret university to near the warm springs bath house the method of construction proposed by the city engineer partly ol of concrete and partly of brick appears to me to be well devised and economical in form and dimensions I 1 recommend that the conduit be circular inside and of 42 inches in diameter and on a grade of one foot in 2000 feet from the corner of fifth south and first east streets to the corner of second south and second west streets thence of 48 inches diameter on a grade of one foot in 2000 feet to the intersection of fourth west and north temple streets and thence of 60 inches diameter on a grade of one foot in 2500 feet for about feet to the terminus in section 12 at an elevation of about feet above the sea the estimates estimate of costs prepared by the city engineer appear to be liberal and so far as an I 1 have been able to judge of the cost of that character ot of work in this locality I 1 have no hesitation in saying that I 1 believe that the whole proponed work can be executed within the estimates As regards regard the existing pumping pant while it is entirely insufficient for the present and future needs of the city there does not appear to be any immediate necessity necessia essit y for its enlargements if the proposed gravity inter oepping sewer is in constructed at once it will then be available for disposing of the sewerage of the bottom lanus for several blocks north and south on fifth south street when the amount of sewage from this district shall exceed gallons a day another outfall main will be necessary and it would be advisable to jay that up to the gravity sewer and pump into that sewer so as to utilize the sewage on the irrigation grounds instead of pumping it into the surplus canal where it can never be of use to any one and would be a nuisance to the adjacent adje cent lands which are now being occupied while at the proposed disposal grounds it would be available for Irrig irrigation stion and even it if not needed could be discharged into the river at a point where no habit are licely to be built for a great many years if as the experience of other cities would indicate as likely the enriched and tempered tampered water supplied from the sewer comes into great demand it will be practicable to increase the normal flow in the sewer by diverting it into some of the surplus waters from city creek anti and the other irrigation canals of the city which are now permitted to lun to waste to the jordan such a disposition of this water might readily be made pending the time that the population pending baa as increased to such an extent as to render the full capacity of the sewer needed for disposal dispo aal of ef the sewage pepper por for the bottom lands lanas north of third south bouth street an additional pumping plant will be needed iu a few years and the sewage should be pumped into the a 1 gravity sewer at or near the warm tp springs rings this whole distrI district cl is so flat that at it will probably be found addan ad van to use some of the pneumatic systems which have proved effective in flat districts and by which the sewage ge of small sub aub districts is col collected looted in h number of sumps bumps and automatically forced by air to a central pumping station such a ao system could be advantageously applied to the whole of the bottom lands landa on both sides of the river within the city limits but the immediate needs of the city appear to demand the disposal and abd utilization ot of the sewage from the elevated and growing districts and this kanbe can be most effectually ind i nd economically accomplished ollo bed by the a 0 instruction of trio intercepting epting gravity sewer newer recommended by the ity city engineer respectfully omitted |