The following text may have been generated by Optical Character Recognition, with varying degrees of accuracy. Reader beware!

4 33, PZ OI6IAAVNILIA 1° A SA EE i, a . ltr vy WINNETKA WEEKLY TALK, FRIDAY, JANUARY 26, 1917 7 Report on Preliminary Report, December, 1916. Present Water Works: There is no need at present to give a detailed description of the present water works at Winnetka. A valuation and description were prepared by C. M. Larson, in August, 1913, in the form of a typewritten report, on file in the illage hall. . y The Winnetka water works serve the villages of Winnetka and Glencoe, with a total of 3,820 acres. These villages are residential in character, and are growing rapidly. The present popula- tion in the two villages is estimated to be 9,000 people, of which 5,600 are in Winnetka and 3,500 in Glencoe. The water is taken from Lake Mich- iga : about 3,000 feet in length, which was built in 1911. Before this intake was built, the water was taken through a 12-inch cast iron intake about 2,000 feet long. This intake is maintained for emergency uses. ¥ The water is pumped from a suction well at the shore end of the intake to the water tower standing on the bluff above the pumping station. This water tower has a capacity of 54,000 gallons. In view of the present population and water consumption in these two wvil- lages, this storage is small, particular- ly during very cold weather, when, at times, anchor ice seriously reduces. the capacity of the intakes. Additional storage is, undoubtedly, desirable. There is at present a pumping capacity amounting to 5.5 million gal- lons, which is sufficient to serve the villages for a number of years to come, QUALITY OF WATER. The water at present is analyzed once or twice a week at the laboratory of the Evanston Health Department. The results of these analyses are on file in the village hall. About one- fourth of these analyses indicate an unsafe water for drinking purposes. These analyses are not on samples of raw lake water, but on samples of the tap water after treatment with calcium hypochlorite. The unsafeness of the water is undoubtedly due to sewage pollution, which reaches the lake from- a number of sources, among which may be mentioned the following: a. Sewage from municipal outlets from towns north of Winnetka. b. Sewage from overflows on Win- netka sewers, which operate during periods of heavy rainfall. c. Sewage from private houses and clubs, along the lake shore, which are so located that they cannot enter the general sewer systems. d d. Pollution carried considerable distances by floating ice. e. Sewage from ships and pleasure boats. f. General pollution from surface run-off. Mod In addition to the bacterial impuri- ties in the water originating from sew- age pollution, the water is at times turbid, due to the action of waves in stirring up the more or less muddy bottom of the lake. This turbidity de- tracts from the quality of the water for nearly all domestic uses. PRESENT TREATMENT OF WATER. The water at present is dosed with calcium hypochlorite at the rate of 6 to 7 pounds per 1,000,000 gallons of water. This hypo is applied to the water in the suction well before it passes through the pumps. The dose is regulated by a standard orifice box, and is practically constant from day to day, and from hour to hour. No routine analyses are made at the pumping station to determine whether too much or too little, or just the right amount of hypo, is being added. It is a fact that the quality of the lake water, as regards its content of bac- teria and organic matter, is subject to constant and abrupt changes. Special tests at Waukegan show that a water from an intake 4,000 feet long, requires a dose of hypo which at times varies from 10 to 25 pounds per 1,000,000 gal- lons in the short space of 24 hours. If the dose were continued at the lower rate when the higher rate was neces- sary, the entire value of the treatment would be practically eliminated. That the treatment with hypo, as practiced here, does not make the water safe for drinking purposes is not to be expected and is shown by the results of the analyses. This becomes particularly important when it is realized that although analyses of the water are made at in- frequent intervals, they indicate that the water is unsafe for about one- fourth of the time, or for one day in every four. NEED FOR FILTRATION. The need for filtering the water should be apparent from the statements already made. However, there are additional reasons why this is neces- sary. Lake Shore Policy. One of the controlling features in determining the desirability of install- ing a filtration plant is the question of the sanitary policy all along the north shore. About two years ago the North Shore Sanitary District was or- ganized in Lake county. During the last two years the trustees of this dis- trict have been making a most ex- haustive study of the sewage condi- tions within their district, and have recently published a report by Alvord, Eddy and Fuller, three of the foremost sanitary engineers in the country. This report recommends that the North Shore Sanitary District must rely upon water purification to assure the purity of the water supply taken from the lake. It states that sewage treatment can be relied upon to reduce the load on the water filtration plants, but that both sewage treatment and water fil- tration plants are necessary. The program which they recommend, as re- gards sewage treatment in the towns from Highland Park to Waukegan, in- volves the treatment of sewage in tanks with disinfection of the tank effluent, and the discharge of this effluent into the lake. While this program may be altered, it is most unlikely that any material change in the amount of sew- age now entering the lake, north of the county line, will come in time to have a controlling influence on the water supplies of the north towns. It is, therefore, my opinion that a diversion or treatment of sewage can- not be relied upon in this district as a means of protecting the water sup- ply. shore Intakes. The water of Take Michigan ig uenal- 1y of better quality farther from shore than near shore. lt is. theielosc, a disadvantage to take water from near shore. If any near-shore water should get into the intakes without the knowl- edge of the operator in charge of the water works, a sudden load of organic matter would come upon the hypo treatment, and practically eliminate its usefulness. Unexpected occurrences of this sort happen on account of broken intakes. An unsuspected break in the intake pipe was the cause of a typhoid fever epidemic at Evanston. A break in the intake pipe at Gladstone, Mich. was not discovered for several months, during ach time polliied water was bein umped to city. The ie way by which the shore Winnetka's Proposed $80,000 Filtration Plant water gets into the intakes is during emergencies caused by anchor ice, or other troubles, when it is necessary to take water from a short intake that can be steam heated. Under the present conditions at Win- netka the installation of a near-shore intake seems unavoidable, to avoid a water shortage due to anchor ice. The hypo treatment is difficult to adjust to these comparatively sudden and un- foreseen changes in the quality of the raw water. A filtration plant of proper design will also provide a storage of filtered lake and supplies it to the people after treatment with hypo. They are at present actively considering methods for financing the installation of a fltra- Lon pant estimated to cost about $150,- In addition to the municipal plants, the government posts at Fort Sheridan and the Naval Training Station, both take lake water and filter it before sup- lying it to the consumers. It appears, therefore, that of the 12 communities from Evanston to Wau- kegan, six are already supplied with filtered water, and four others are at n through a 80-inch cast iron intake $80,000.00, Ee EIS Coagulation, Basins J75 004 gal Crear We// 574000 gol lead House WINNETKA, ILL. / WATER FILTRATION PLANT 7 Scale: lin=30% PEARSE AND GREELEY Hydraulic & Sanitary Engineers 64 W. Randolph St. Chicago, Iii. Diagram of Proposed Plant. water amounting to from 3 to 5 hours' supply in addition to that already in the water tower, thus remedying a de- fect in the existing plant. In view of the present quality of the Winnetka water, and of the present practice certain to continue, of dis- charging some sewage into the lake, and in view of the uncertainties of the hypo treatment, the need for a water filtration plant is beyond question. OTHER COMMUNITIES, In undertaking the installation of a filtration plant, costing upwards of it is pertinent to inquire about the practice in neighboring com- munities. This is briefly summarized as follows: Evanston. Two years ago, Evanston installed a rapid sand filter plant with a capacity of 12,000,000 gallons per day, which cost slightly over $200,000.00. This plant has given marked satisfaction to the residents in Evanston and Wilmette, whom it supplies with water. Wilmette. Wilmette at present takes filtered water from Evanston. The present orice is 6c per 1,000 gallons. Evanston has notified Wilmette that the rate is to be increased to 8c per 1,000 gallons to pay for filtering the water. n this account, Wilmette has had its water supply situation investigated by an engineer, who recommends that Wil- mette install a filtration plant. A filtered lake water is preferred to a possible deep well water supply, and raw lake water, without filtration, is condemned. Kenilworth. The Xenilworth water ig is filtered through the old type of pres- sure filters. While these filters are not usually as efficient as the open gravity filters, than no filter at all. Highland Park. Highland Park is at present supply- ing raw lake water to its people. The water supply is listed by the Illinois State Water Survey as among the 18 worst water supplies in the state. An- alytical data thoroughly substantiate this rating. Lake Forest. Lake Forest is supplied with a filtered water treated with hypo. The filters are of the old-fashioned closed pressure type. However, Lake Forest is fortunate in haying a first-class superintendent in charge of the water works, who makes routine laboratory analyses, and the water supplied is, therefore, of satisfactory quality. Lake Bluff. Lake Bluff takes its water from deep wells, and is, therefore, not troubled with lake pollution. However, the well water is hard, and is, therefore, un- satisfactory from this point of view. North Chicago. North Chicago takes its water sup- ply from Lake Michigan, and delivers it to the people after treatment with liguid chlorine. In the fall of 1915, plans were made up for a filtration plant, and a bond issue was submitted to the people early in 1916, the bond issue being defeated. During the winter of 1916, there was a considerable amount of typhoid fever in the city. The officials, however, recognize the need for filtration. Waukegan. Waukegan now takes its water sup- plv from a point 4,000 feet out in the Ts dn, Cy mmm. RC nevertheless they are better! present actively considering the stallation of filters. One uses well water. The policy of water water fil- tration along the north shore is thus reasonably established. A Eariler Reports. The desirability of water filtration for Winnetka was investigated by Al- vord and Burdick, sanitary engineers of Chicago, in 1907. They state their conclusion as follows: "We recom- mend that the necessary gravity filtra- tion Fjant of 1,000,000 gallons capacity per 24 hours be constructed. While there is no evidence that the com- munity is suffering or has suffered from polluted water supply, we believe that physicians and sanitarians will join in the opinion that the present supply is, at best, dangerous, or detri- mental to health,, and that compliance with enlightened sanitary practice re- quires both the discontinuance of the present lake pollution and the better supply." . This report was written in 1907. Dur- ing the last nine years there has been a substantial increase in the popula- tion, and there is no reason to con- sider that conditions have changed fovarobly. In fact, Messrs. Alvord and Burdick have expressed this view in a letter received by the Winnetka council in the spring of 1916. SIZE OF FILTRATION PLANT. The necessary size of filtration plant depends upon the estimates of the growth of population, upon the con- sumption of water, and upon the time in the future for which it is con- sidered advisable to build the plant. These matters we have looked into tentatively as follows: Population. The past population and the esti- mated future population of Winnetka and Glencoe are shown in Table 1, the past population having been taken from the U. 8. census. In forecasting the future, we have compared the growth of Winnetka and Glencoe with the growth in two other residential and metropolitan communities, as their population has increased beyond that of Winnetka and Glencoe. This com- parison is shown graphically in Figure 1. It appears that by the year 1925 the combined population villages will 16,100 people. Water Consumption. The water consumption in Winnetka and Glencoe is computed from the rec- ords of the individual meter readings in Winnetka, and the meters on the main supply line to Glencoe during 1916. The consumption has ranged anproximately as shown in Table 2. For residential communities having meters on most of the house connec- tions. the water consumption is liberal. We do not think that there is any need for increasing the allowance and in fixing the necessary size of the filtra- tion plant, we have used the figures of Table 2. Future Provision It does not appear unreasonable to build a plant of sufficient capacity to serve until about the year 1930. A filtration plant of the type pro- posed can filter water satisfactorily for short periods by overloading it above the rated capacity up to form 30 to 50 per cent. On this basis, the size of plant necessary in the years 1925 'and 1930 with varying conditions and overload to handle the maximum day and the average day in the maxi- mam month are shown in Table 3. From this data, it appears that a plant in- in the two probably have reached with a capacity of 3,000 allons is ample to meet the reasonable future requirements of the two villages. GENERAL ARRANGEMENTS. There seems to be little doubt that the best type of plant for the villages of Winnetka and Glencoe is an open gravity rapid sand filter. This matter is, or has, already been looked into by various authorities at Evanston, Win- netka, North Chicago and Waukegan, and in each instance this type of filtra- tion plant has been recommended. Plans of the existing water works have been studied and a tentative ar- rangement of the new filtration plant at this site has been laid out as shown in Fgure 2. This lay-out should not be considered in any sense as final, but only to show that a filtration plant of this capacity can be built, at the site of the present water works with rea- sonable allowance for future condi- tions, to serve beyond the year 1930. The lay-out is the basis for estimating the cost of the proposed new filtration cent of the total cost. These and other prices have all been adjusted to pres= ent day market prices. Although these market Prices are high, there is no means oO Juaging the future, and they may go still higher. We estimate, therefore, that a 3,000, 000 gallon filtration plant at Winnetka can be built at present prices for ap- proximately $80,000.00. In addition, there must be an allowance for engi- neering and contingencies amountin to about 6 per cent, making a tota cost of, say, $85,000.00. FINANCIAL ASPECTS. An important element of this pro- ceeding is the means for financing the work. This involves not only the se= curing of funds, but also the necessary charges for supplying filtered water, particularly to Glencoe, who is now purchasing water from Winnetka on an unfiltered basis. An estimate of the value of the present Winnetka water works has been made by Mr. Fitz- plant. gerald, pie has been added the cost o e ration plant as estimated ; ESTIMATES OF COST. above. The necessary charge per 1,000 While we have not prepared an gallons to carry the existing and pro- posed plant costs have also been worked out on the basis of the water consumption during the six months ending September 30, 1916. itemized detailed estimate of cos have adjusted the figures on file 3% Aik office to the condition accordance with ot Winngtanin the € r This data shown in Figure 2 Eu Den is all shown in Appendix 1. E wn in i : actually "computed Lk hI e hove Glencoe is at present paying Win- netka at the rate of 7c per 1,000 gal- lons of water. To furnish them with filtered water it is necessary to increase this rate to 9¢ per 1,000 gallons. cavation, the yardage of concrete, and ihe cost of the necessary buildings. hese items constitute about 40 per TABLE 1. Past and Estimated Future Population of Winnetka and Glencoe. y Population ear Winnetka Glencoe Total 1890. vriviivie ss SPS oa etl ae 1,079 ; 1990 nian ales ale lens us 0x ee ve x 1,833 : 1,020 2,358 510 poe tar ee kaa tinan yi C2108 1,899 > 5,067 1000 nine rns ry LR, 7,100 5,300 12,400 jae PEAR A teesasas 10,800 8,800 19,600 AIIRIE Dip gil severe sens 14,700 12,700 27,400 TABLE 2, : Statistics of Water Consumption for Winnetka and Glencoe, Ill., During 1916, Rate of Pumpage---- Gallons Gallons Per Per Capita Da, Annual Average ........ . .,.... 00 oa IRI IT 1,100 700 Pe ay Maximum Month ......... ... 0 Saas 1,630,000 163 Maximum Day foc oe Lr IRE 2,250,000 225 TABLE 3. 4 Filter Plant Capacities Under Varying Conditions. 150% Overload 133% Overload 150% Overload 133% Overload on Maximum on Maximum on Maximum on Maximum Thar > foo Day Month Month 1930... vail ceeds 2,950,000 3320.000 2130.00 3.400.000 Per Million Gallons ITEM Total Capacity Excavation, 2,200 eu. vad. @ $1.50. 1... oR $ 3,300.00 $ 1,100.00 Reinforcing Steel, 100,000 1bs. @ 0.06...............00v..... 6,000.00 2,000.00 Conerete, 983 yO. Qi BIBBOL Ga ie tees 3 . 13,500.00 4,500.00 PIPING LL fev Ss , Ce NS Solution PIDINg. ive sin ceive ea a eae TR ae a. %000% VAIVEBL. oh sin vensaneneinesians OE a al eka 300.00 Hydraulic: Valves . o. i aida os vase adn TY a 750,53 OO GE rr oe ts is a Lt Be Rate CONIOIErE .\ i... or ves isn nt vias dani ns vo ansies saihei 3,000.00 1,000.00 Buildings, 36,750 'cu. ft. @ $0.364... LL 0. sin: 6,000.00 2,000.00 Chemical Feed Boxes. :.... uo... 0. 0 i ho 225.00 75.00 BleotricAl WOTI . =) Sia aS Sp NP a ed a Ra 250.00 PlombingcandEeating. un no CRE 850.00 Laboratory and Equipment............ Ra i re RR os seine 170.00 Filter Gravel .......cc.ex... inlet wiatetein Sos Vries vie siete ER 250.00 Filter Sand ........ PRIN LOY HAR ATER EEN oo ie ately PEE 450.00 DONAErATAING vce sn essvian sine vedesdohs See via aie 0 aibbee evs wie a ER 1,000.00 Operating Tables .............. Sia's ec ue viennieis bininie stinie nx 00 3, 400,00 800.00 Grading and Ground Improvement............ AREER, evaivie's 500.00 Connections ....... PES, TENA a CPR Ee A WE Pears ene CaF aie eae 300.00 TOW LAL PUMPS. «cov vvvisiioe esl iia alil NE A RE BL 3,000.00 Allowance for extra foundations, wet excavation and uncer- BAIN DIGCES rv v ir tvie dis cme nnn sme soded Pree vss ies TE Rees 1,800.00 Sm-- $23,270.00 Contingencies, 156% ......... PERL Krk eR Rea a aa ives a eee bein SS S008 Vrm---- Or, $81,000.00 for a 3,000,000 gallon plant. 327,000.08 APPENDIX 1, Glencoe Water Rate--Present Conditions. Plant Value 4-1-1916--Higgins Audit-- Buildings ........ sapere ie vistas tsa seen nnenenesesse315,266.47 Wells .......... 50s -0: AER EN Siva ae cae iienniee 9,760.00 TOWEL tes snvos sss "ins Tan enw sais wis ave ee Csr w sews 34,018.56 Plant Bauipment . i ed he se 13,973.28 Shop Equipment .... 0... ...0 00005 Fg SO A 983.25 Intakes and Suction........../... ' cr ven wena ivy suns 44 303.95 ---- $91,705.33 12-inch water main from Plant to Glencoe Limits................ .$ 5,000.00 Probable cost of Filtration Plant............ ress senrasnsrnenness 35,000.00 Pumpage for Six Months Ending September 30, 191 Winnetka oo... 000.00 ER Se I Ne aa eenns 121,298 =--595% GIeNC0R ivr snnrecsnses ce nie ME a ina taeinie i seecenena.s 82,134=--40.5% yr NR a LL A aie vv sire ven. 203,431 Glencoe Costs-- Eight per cent in plant investment, 5 per cent interest, 8 per cent depreciation, 40 per cent Glencoe share. .40 x .08 x $91,705.31-- $2,934.55 Five per cent interest, 2 per cent depreciation on 12-inch main. $7 per cent .of $5,000.00 (entire COSY. «uve reenssnreaneiness .. 350.00 -- Total fixed charges....... san donne waists ae sii trees srsaraennee+$33,284.58 Operating Expenses, Year Ending March 21, 1916-- Pumping Expense ...... NAT a A «..$11,242,78 -- 3.38 M. Gals Total Pumpage....videifebade dali ise. ven ++...323,372 M. Gals. Glencoe Pumpage, 40%. «. iv ddnn ditt ive ..132,908 M. Gals. Fixed Charges, Glencoe Proportion. i gnu} $3,284.55 . : 132,908 -- 2.48 M. Gals. Total Cost Glencoe Water... .....covnsviesirnrisdsiavais tesa ...5.86 M. Gals, Contingent Allowance ......... Cr nO eee ate eee + van simon vals lvld Selling Price... 00 aes Fr aehie inte ieiy nie 8 rs A AO o's 2a 7.00 GLENCOE WATER RATES. Additional Cost for Filtered Water. Estimated Cost of Filtration Plant.........cvesveeu. $85,000.00 Interest and Depreciation at 8 per cent.............. 6,800.00 Glencoe's Proportion 40 per cent......... en Shoe TL 2,720.00 Fixed Charges per M. Gallons.......... Ne EEE, wes vn 2e + 3720.00 132,908 = .0206 per M, Estimated additional operating expenses for Filtration 0114 Total AdQitional EXDENSBe. .. vers shinaintsenssmvvves ss .0320 per M, Present Cost ..............5.86 cents per M. Additional Cost ...........3.20 cents per M. Total Cost Filtered Water..9.06 cents per M. Reasonable rate at which to sell water.. ...9.00 cents per 1,000 gallons NOTE--The above figures do not include any allowance in operating ex-~ penses for distribution expense, office expense, or meter repair expense.