Loading...
HomeMy WebLinkAbout08 EMERGENCY REPAIR OF WALNUT WELL 06-03-08AGENDA REPORT MEETING DATE: JUNE 3, 2008 TO: WILLIAM A. HUSTON, CITY MANAGER FROM: PUBLIC WORKS DEPARTMENT/WATER SERVICES DIVISION SUBJECT: EMERGENCY REPAIR OF WALNUT WELL SUMMARY Walnut Well recently experienced a mechanical failure. Detailed inspection has determined that various parts of the well pump and shaft need to be replaced to make the well operable. It is critical that Walnut Well be returned to service as quickly as possible to meet the operational, emergency and fire flow requirements of the City's water service area. Resolution No. 08-35 ratifies the Public Works Department's decision to dispense with regular public works bidding requirements and pursue emergency repairs to Walnut Well. RECOMMENDATION It is recommended that the City Council: 1) Adopt Resolution No. 08-35 by four-fifths vote of its members declaring that the public interest and necessity demand the immediate expenditure of public money to repair Walnut Well to safeguard life, health and property; and 2) Authorize the $63,453.60 from the Water Division's FY 2007-08 Operations Budget to complete repairs to Walnut Well. FISCAL IMPACT There is an adequate fund balance in the Water Division's Operating Budget for FY 2007/2008 to cover this unexpected expense of $63,453.60. This repair expense may be partially reimbursed to the City through the submittal of a claim to the City's insurance carrier for mechanical equipment failure . BACKGROUND Walnut Well unexpectedly experienced a mechanical failure. This has required the City to make up lost groundwater production through purchases of imported water from East Orange County Water District at an added water cost of $454 per day. Walnut Well was drilled in 1923 by Irvine Ranch, and was acquired by the City of Tustin in 1980. Despite its age, its current production rate exceeds 800 gallons per minute (gpm). The City retained a well contractor, General Pump Company, to pull the well pumping equipment and determine what caused the mechanical failure. General Pump found that various parts of the well pump and shaft must be replaced to make the well operable, and extend the life of the well. The estimated cost to complete this work is $63,453.60. Due to the significant lead time required to obtain replacement equipment, Walnut Well is projected to be back on-line by July 18, 2008. A copy of General Pump's letter proposal dated May 6, 2008 is attached for the Council's information. Emergency Repair of Walnut Well Page 2 June 3, 2008 The loss of Walnut Well is of major concern for the following key reasons: (1) the loss of water production at Walnut Well results in lower water service pressures and water supply locally, which is significant since customer water demands are increasing with warmer weather; (2) water production from Walnut Well is needed to offset the temporary loss of production from Well No. 4 at the 17th Street Desalter, plus decreasing production from the City's other older wells; and (3) possible reductions in imported water supplies if Metropolitan Water District of Southern California implements its new drought allocation plan. Without Walnut Well, the City's water system may not be able to adequately respond to operational, emergency and fire flows that may be required during peak demand periods. The adoption of Resolution No. 08-35 would authorize the Public Works Department/Water Division to dispense public bidding requirements and enter into a contract with General Pump to complete the repairs. Note that if the City's Purchasing Policy and Procedures are applied to Walnut Well valuable time would be lost in bringing the well back on line, especially with growing warm weather demands and potential emergencies. Tim D. Serlet Director of Public Works/City Engineer Fred J. Adjarian Water Service Manager Attachment: Resolution No. 08-35 Letter of Proposal Emergency repair at Walnut Well & Reso. 08-35 RESOLUTION NO. 08-35 A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF TUSTIN, CALIFORNIA DECLARING THAT THE PUBLIC INTEREST AND NECESSITY DEMANDED THE IMMEDIATE EXPENDITURE OF PUBLIC MONEY TO REPAIR WALNUT WELL TO SAFEGUARD LIFE, HEALTH, AND PROPERTY WHEREAS, groundwater production at Walnut Well has stopped due to the mechanical failure of the well equipment; and WHEREAS, Walnut Well is a critical component of the City's water supply system, with a capacity of approximately 800 gallons per minute; and WHEREAS, the loss of production from Walnut Well has resulted in lower water service pressures and water supply to the immediate area because customer water demands are presently increasing with the onset of warmer weather; and WHEREAS, without groundwater production from Walnut Well, the City's water system may not be able to adequately respond to operational, emergency and fire flows that may be required during peak demand periods; and WHEREAS, the City's imported water supplies may be reduced in the event Metropolitan Water District of Southern California implements its drought allocation plan. NOW, THEREFORE, BE IT RESOLVED that in accordance with Section 22050 of the Public Contracts Code and based on the substantial evidence set forth in the agenda report, that this emergency repair will not permit a delay resulting from competitive solicitations of bids and that this action is necessary to respond to the emergency; AND BE IT FURTHER RESOLVED that the Public Works Department's decision to complete the repair of Walnut Well without soliciting competitive bids is hereby ratified. PASSED AND ADOPTED at a regular meeting of the City Council of the City of Tustin held on the 3~d day of June 2008. Jerry Amante, Mayor ATTEST: City Clerk GENERAL PUMP COMPANY 159 N. ACACIA STREET SAN DIMAS, CA 91773 PHONE: (909) 599-9606 FAX: (909) 599-6238 WELL & PUMP SERVICE SINCE 1952 Lic. #496765 May 6, 2008 City of Tustin Water Services Division Public Works Department 1472 Service Road Tustin, California 92780 Attn: Mr. Art Valenzuela, Water Treatment Supervisor Subject: Repairs to City of Tustin's Walnut Well Dear Art: General Pump Company has completed the tear down and engineering inspection of your Walnut deep well water Tube pump. Below is a summary of our findings. Additionally, please find attached digital photos, highlighting the damage sustained by individual well parts and equipment. Summary of Findings: (1) Column Pipe: The 10" column pipe is in poor condition and MUST be replaced. The majority of the column joints were cut and most of your drop-in retainers spun in the column pipe causing the couplings to be severely grooved. The retainers support your line shaft at 10' spacing. The retainers keep your shaft from whipping. Your shaft turns at 1780 rpm, but your retainers must remain trapped in the column coupling. If the retainer begins to move, the retainer OD gets smaller due to wear and the column coupling becomes grooved allowing the retainer to rotate faster and the line shaft will vibrate damaging your pump.. We will install an upgraded retainer called a threaded retainer which will help save your pipe and pump from premature failure in the future. (2) Pump Bowl: The Gould's model 11CLC which is somewhat of a light weight bowl assembly was found to have severely worn bowl bushings. The bowl bushings keep your bowl shaft straight. Once the bushings wear, the bowl impellers will eventually be damaged causing the pump to stop pumping. Some bushings were completely worn out to a point that the bearing housings were also worn, therefore the bowl assembly will need to be replaced. (3) Shafting: The shafting will need to be replaced. This pump has carbon steel shafts with stainless steel sleeves. This type of shaft is cheaper than the City of Tustin's standard design of all 416SS shafts but in the long run cost you more. The 416 Stainless Steel [SS] shafts can be re-used by flipping or changing bowl stick up giving these shafts a longer life. In addition, the 416SS are approximately 30% stronger. Mr. Art Valenzuela City of Tustin May 6, 2008 Page -2- (4) Discharge Head: Your discharge head is a cast iron component that connects the motor to the pump and appears to be in fair condition. The head couples your vertical column assembly to the distribution piping. We will rebuild the packing box, sandblast and paint this part. (5) Suction/Cone Strainer: Your suction pipe and cone strainer (8") will be replaced. Repair Cost Estimate: General Pump is waiting on pricing on many of the Walnut Well replacement parts. However, we know the cost of the 10-inch column pipe. • The estimated cost to replace 245 feet of existing pipe with new column pipe $16,653.60 • The engineering estimate to replace the bowls, retainers, suction, 416SS shafts, couplings, rebuild head, shop labor, machining, including freight and sales tax 40,000.00 • Re-installation of column pipe, well pump plus well start-up and inspection 8,800.00 The total engineering estimate to complete all of the repairs to the City's Walnut Well as described above is .......................................................$63,453.60 As was discussed in detail with Bart Crowley last Friday, the availability of steel pipe in the U.S. is getting to be a real problem. In my 25 years, I have never seen anything even close to some of the delivery times we have been quoted on the column pipe. Not that it matters for this job, but vertical motor deliveries for sizes 200HP and smaller have always been about a week for standard vertical W.P.1 premium efficient motors. However, now it can take 12 weeks depending on the order and U.S stock. The good news is we have purchased the column pipe, which is due to arrive in the latter weeks of May. The rest of the pump equipment should be ok to purchase later next week (once the Water Services Division has obtained the necessary internal approvals). General Pump is tentatively scheduled to install the repaired pump in about a month. Please call me at (909) 599-9606, x 222 if you should have any questions. Sincerely, GENERAL PUMP COMPANY, INC. Michael Bodart Michael Bodart Director of Engineering