Agenda Packets - 1987/03/16 - Laserfiche WebLink

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W,r,.. I `/ MEMO TO: Clerk -Administrator and City Council FROM: Public Works Foreman Rose DATE: March 12, 1987 SUBJECT: WELL NO. 1 MAINTENANCE AND REPAIR PROJECT 1986-1 During the summer of 1986, inspection and maintenance of Well No. 1 pump and motor occurred. You may also recall extensive repair of the electrical system that occurred due to an electrical explosion. Although the well's pump and motor were replaced during that summer due to their wear and condition, they were never Put into service at that time because of the electrical and control systems being inoperative. The electrical and control systems were finally operational approximately two months ago, and Well No. 1 was put into service. Upon the initial monitoring and testing, Well No. 1's expected production of 1,000 gallons per minute was not being met. Further testing and analysis took place with the contractor, Bergerson-Caswell, and those finding also concluded that the production would range between 725 and 850 gallons per minute. Staff did further exploration and found that the original bid information was incorrect with regard to static, draw -down and total dynamic head footage. Minor corrections were made during the inspection process, but the major significance was missed; total dynamic head. During March of last year, our Engineer at that time recommended, and you approved, the project addendum for a new pump and new energy efficient motor. They were a 5 stage, 12" trimmed impeller, Delta pump and a 125 hp Newman, 91% efficient motor. The worn equipment was a 7 stage, 12" trimmed impeller, Fairbanks Morse and the same brand motor, 81% efficient. The new equipment will not provide the required 1,000 gallons per minute primarily because of the subtraction of the 2 stages. It is important for the City Water Department to have wells that will provide a minimum of 1,000 gallons per minutes for two major reasons: At all well sites, the injection of chemicals occur when the well is running. This injection rate is based on 1,000 gallons per minute. Although it can be adjusted to any rate of flow, the flow should be constant to allow for proper chemical feeding. The City had been on an energy program for a year and a half which has saved us considerable dollars.. When Staff calculated the feasibility of going to energy off peak, it was based on our storage capabilities and pumping rates. The pumpinj rate used was a minimum of 1,000 gallons per minute per well in operation.