OKLAHOMA CITY WATER SYSTEM
The rapid growth of Oklahoma City, Okla., has made it necessary to take immediate steps toward increasing its water supply. Since the present system was projected the city has more than quadrupled its size, and to-day its inhabitants number about 65,000. For the past three months Alexander Potter, a civil engineer from New York, has been studying the conditions at Oklahoma City with a view of planning some method by which the water supply might be increased, and recently presented his plan to the city council. It calls for an expenditure of at least $1,250,000, which would give the city one of the best systems in that part of the country. Mr. Potter’s scheme calls for a reservoir dam along the North Canadian river about eighteen miles west of the present waterworks. The capacity of the proposed reservoir will be 7,500,000 gallons, or enough to supply a city of 150,000 inhabitants 365 days. A resolution authorizing the mayor to call a special election for the purpose of voting bonds for the water extension was passed by the council. The bonds will amount to the sum suggested by Mr. Potter in his report, $1,250,000, which is estimated as being sufficient to cover all costs for the proposed improvement.
“1 expect to call the election for the voting of these bonds in January,” said Mayor Lackey. “The water improvements are something that every citizen of Oklahoma City realizes the need of, and I hope that the bonds will pass.”
The consideration of the North Canadian river as the most feasible source from which to secure an increased supply of water for Oklahoma City was reached by the process of elimination. Mr. Potter says that he investigated various schemes, including the bringing of water from Arbuckle mountains, the supply at Woodward, the possibility of a supply from underground sources, the damming of Mustang creek, etc. Details concerning all the investigations are given in the report, which is clear and to the point.
After eliminating all the projects mentioned, according to the report, the problem then was to secure the most advantageous site for the construction of a dam which would form a reservoir capable of supplying the needs of the city. The recommendation of the consulting engineer includes the building of a reinforced concrete dam 1,000 feet long with a maximum height of 32 feet. The dam will be constructed so that its entire length can be used as a spillway, thus regulating the extreme height of the water from the greatest known flood which would cause the water to rise less than one foot above the spillway level. Normally the water will pass over a section of the dam, which section will be 200 feet long and will be constructed 3 1/2 feet lower than the remaining 800 feet. It is proposed to equip this 200 feet section with flash boards which will be operated by hydraulic lifts, for the purpose of raising or lowering the waters in the dam to meet and regulate flood conditions. The report points out that regulations of the stream by means of this dam will almost entirely obviate the necessity of money for widening, straightening and regulating the North Canadian river as it runs through the city. The proposed construction of this dam and reservoir will preserve the waters of the North Canadian within its banks at all times, save under the most abnormal flood conditions known to the river. The estimated saving to the city by the elimination of this flood relief work is estimated at about $500,000, and the enhanced value of farm lands in Oklahoma county alone is set down at $1,000,000, 20,000 acres being thus affected, the enhanced value of which will be approximately $50 per acre. Farms within two or three miles, of the city will, of course, have a greater enhancement in value, as farms in the bottom lands of the North Canadian arc already being laid out and sold for city lots. The report sets forth the following facts in reference to the size of the reservoir. The capacity of the reservoir thus formed, up to the flow line, will be 1,000,000,000 cubic feet or 7,500, 000,000 gallons of water. When the city is using 20,000,000 gallons per day to serve a population of 150,000 people, the reservoir will hold a reserve supply for 375. days, on the assumption that only sufficient water is entering the reesrvoir from the stream to replace evaporation and percolation. This evaporation and percolation is represented hv the average flow of the year, and will gradually become less as time goes on. When the city is using 30,000,000 gallons per day and supplying a population of 275,000 people, the reservoir will hold a reserve for 250 days’ supply, provided there is only sufficient water flowing into the reservoir to compensate for evaporation and percolation, as stated above. The reservoir when full will flood about 3,300 acres of ground, and the recommendation of the engineer is that the city purchase at least 4,000 acres of ground in order that it may control and preserve the shores of the lake thus formed. To give some conception of the size of the lake thus formed, it should be stated that the width of the lake will be one and three-quarters miles for about two miles of its length ; while from the dam to where the water first enters the lake the distance will be approximately eight miles. While the capacity of the lake is thus seen to be large, the water will have no opportunity of becoming stagnant, for the average flow of the North Canadian river for the last eight years has been sufficient to entirely change and renew the water in the lake at least eight times each year. The report states that the engineer sees no reason for denying the use of the lake for boating and fishing within certain restrictions, and suggests that beautiful additions to the boulevard system and capitol improvements could be made by the construction of a boulevard from the front of the capitol building directly to and around the lake, and that the land owned and controlled by the city around its shore be improved and utilized, under proper restrictions, either for park purposes or for the erection of beautiful residences, with sanitary provisions, under the direction and regulation of the city. The report further points out that, while this immense reservoir will act as a settling basin for the city’s water supply, thus improving the bacterial condition of the water a thousandfold over present conditions, that the water will still remain hard and disagreeable for all domestic uses and manufacturing purposes, and that this can only be overcome by the construction of a modern treatment plant for the softening and purification of the water at the present city pumping station, and plans and estimates for the construction of such a plant are presented with the report. It is purposed to convey the water front the reservoir to the city pumping station by a 42-inch reinforced concrete or wooden conduit eight miles long. This will be sufficient in capacity to serve the city until it reaches a population of at least 150,000, at which time the pipe line should be duplicated. The total cost of the improvements thus outlined in the report is as follows: Land for reservoir, $400,000; dam and reservoir construction, $325,000; pipe line to city pumping station, $200,000; water softening and purification plant, including the remodeling of existing purification plant, $175,000: extensions and improvements within the city, $50,000; total, $1,250,000. The report recommends that, in order to coyer all possible contingencies and leave some margin for future city extensions and other purposes. the bond issue lie called for $1,250,000. The report says that the saving in pumping expenses alone, because of the ability to lead the water to the plant by gravity, will pay for the cost of the pipe line, and that the receipts of the water company over expenditures will be sufficient to pay for the entire project without raising the water rates to the consumers.
The present water supply of Oklahoma City is taken from wells by direct pumpage, a sand filtration system being employed. There are two Knowles pumps with a daily capacity of 2.000,000 gallons, 24 miles of cast-iron mains, 138 hydrants of the Mathews & Ludlow make. 107 Ludlow and Crane valves, and 1,700 service pipes. The domestic pressure is 100 pounds, and the fire pressure 150 pounds. The cost of the old works was $100,000.