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Dubuque Water Supply Well Repair and Rehabilitation Project 2020_Initiate Copyrighted September 21, 2020 City of Dubuque Items to be set for Public Hearing # 3. City Council Meeting ITEM TITLE: Dubuque Water Supply Well Repair and Rehabilitation Project 2020 SUM MARY: City Manager recommending initiation of the bidding procedure for the Dubuque Water Supply Well Repair and Rehabilitation Project, and further recommends that a public hearing be set for October 5, 2020. RESOLUTION PreliminaryApproval of plans, specifications, form of contract, and estimated cost; setting date of public hearing on plans, specifications, form of contract, and estimated cost; and ordering the advertisement for bids SUGGESTED Receive and File;Adopt Resolution(s), Set Public Hearing for October DISPOSITION: 5, 2020Suggested Disposition: ATTACHMENTS: Description Type Dubuque Water Supply Well Repair and Rehab City Manager Memo Project-MVM Memo Dubuque Water Supply Well Repair and Rehabilitation Staff Memo Project 2020 Resolution to Initiate Dubuque Water Supply Well Resolutions Repair and Rehabilitation Project 2020 Dubuque THE CITY OF � ui-Aseria cih DuB E , . � . , � II � Maste iece on tj2e Mississi i zoo�•zoiz•zois YP pp zoi�*zoi9 TO: The Honorable Mayor and City Council Members FROM: Michael C. Van Milligen, City Manager SUBJECT: Dubuque Water Supply Well Repair and Rehabilitation Project 2020 (Wells 3, 6, and 8) (Account No. 64042795-73211) DATE: September 15, 2020 Water Department Manager Denise Blakeley Ihrig recommends initiation of the bidding procedure for the Dubuque Water Supply Well Repair and Rehabilitation Project, and further recommends that a public hearing be set for October 5, 2020. I concur with the recommendation and respectfully request Mayor and City Council approval. v Mic ael C. Van Milligen MCVM:jh Attachment cc: Crenna Brumwell, City Attorney Teri Goodmann, Assistant City Manager Cori Burbach, Assistant City Manager Denise Blakeley Ihrig, Water Department Manager Dubuque THE CITY OF � All•p�eeriea Ciq Du B E �v�s.�� , .. , � �����, I I Maste 12CE 011 t�1e M1SB1S51 2 zoo�•zoiz=zois � pp zoi�*zoi� TO: Michael C. Van Milligen, City Manager FROM: Denise Blakeley Ihrig, Water Department Manager DATE: September 15, 2020 RE: Dubuque Water Supply Well Repair and Rehabilitation Project 2020 (Wells 3, 6, and 8) (Account No. 64042795-73211) INTRODUCTION The purpose of this memorandum is to request City Manager and City Council authorization to seek competitive bids for the repair and rehabilitation of Wells 3 and 6, and modification to the airline in Well Number 8. These improvements include removal, inspection and possible modification of the pump to improve pump efficiency, completion of a televised inspection of the well, examination of the well casing, and installing new air and water sample lines. The enclosed resolutions authorize the public bidding procedure for the Dubuque Water Supply Well Repair and Rehabilitation (Wells 3,6, and 8) Project 2020. BACKGROUND The City of Dubuque's source water supply is pumped from five shallow and four deep wells. The five (5) shallow alluvial wells, Wells 2, 3, 4, 9, and 10, are located on the Hawthorne Street boat ramp peninsula of the Mississippi River. Well depths vary from 127 feet to 200 feet below ground level, and all are cased to 100 feet. Individual well capacities range from 1.55 to 3.30 million gallons per day (MGD), with a theoretical combined capacity of all five wells at 14.15 MGD. The four (4) deep wells, Wells 5, 6, 7, and 8, are located within a 1,500-foot radius of the treatment plant. The wells are cased to 500 feet below ground elevation and individual well depths vary from 1,000 feet to 1,800 feet below ground. The individual well capacities range from 0.9 to 3.25 MGD with the theoretical combined capacity of 9.6 MGD. The City's Water Department operates and maintains the wells to their maximum available capacity to ensure the City is ready to serve changing water demands. The wells are operated in rotation to allow water levels to recover in the well column and to reduce and prevent cavitation of the well pump in the event the water column is drawn down too far. The wells must also be maintained to ensure the pumps are operating efficiently, the well casing is in good condition, identify issues with the well borehole, and inspect the air and sample lines. DISCUSSION Well No. 3 and Well No. 6 Well No. 3 was constructed in 1956, it is 28-inches in diameter to a depth of 200-ft, and has an average pumping capacity of 3.5-million gallons per day. The well is formed in the alluvial sand and gravel geology along the Mississippi and has been identified as having loss or reduction in pumping capacity. The loss, based on earlier maintenance records showing application of an acid, is indicative that there was most likely mineral scaling which would plug the well screen and reduce pumping capacity. The acid is used to dissolve the mineral deposits. The well was treated with an acid application in 1963, 1982, 1995, and was jetted in 2013. Current measurements show the well to be pumping an average 2.5 MGD or 40% below its capacity. Further, in July 2020, the well tested present for total coliforms, while no fecal coliforms were present, the well was taken off line pending further investigation. The well site was inspected by William O'Brien from Water & Resource Recovery Center and it was determined the sampling line and sampling port should be relocated and replaced during well maintenance. In addition, as it is unclear where the coliforms are originating, the well should also be shock chlorinated along with all internal well lines. Well No. 6 was constructed in 1935, is 24-inches in diameter to a depth of 1,504-ft, and has an average pumping capacity of 2.5-million gallons per day. The well has been identified as having loss or reduction in pumping capacity. The reduction in pumping capacity is attributed to possible wear and tear on the pump bowls and the location of the pumping bowl assembly in the well borehole. The current pump is estimated to be producing 1.5 MGD or 1,050 gallons per minute at a pump efficiency of 63%. According to pump manufacturers, the BEP or best efficiency point will be experienced between 70% and 120%, according to the Hydraulic Institute the optimum best efficiency point is 85%. If a pump is operating outside of its BEP, energy is wasted leading to increased electricity costs and the pump will most likely experience premature wear and tear leading to loss of pumping capacity. Well No. 6 was last inspected in 2003. In both cases, to more accurately determine if the loss of capacity is associated with pump wear and tear or other well borehole issues such as screen plugging, the recommendation is to obtain cost estimates from a State of lowa certified well and pump contractor to pull the pump bowl assembly from the well, inspect the pump and appurtenances along with an inspection of the borehole. The contractor will be responsible for disconnection of the motor and removal of the pump bowl assembly. The contractor will then remove the well column pipe so the wells can be televised to determine the condition of the borehole, screen, gravel pack, and casing. Having removed the motor, pump bowl assembly, and column pipe, the contractor will perForm an inspection and examination of the pump, motor, and column pipe in a controlled environment where an in-depth evaluation of the assembly can be conducted to determine if the pump assembly or column pipe needs to be replaced or rehabilitated to improve efficiency. The request for bid will include a cost for replacement pump bowl assembly, column pipe rehabilitation, shock chlorination, application of an acid or air- shocking, and downhole well televised inspection. Well No. 8 Well No. 8 was last repaired and rehabilitated in 2016, however the air-line is no longer functioning properly to provide the well water levels. It is necessary to report the static and pumping water levels to the lowa Department of Natural Resources and should be resolved as soon as possible. PROJECT SCHEDULE The schedule for the project is as follows: Initiate Public Bidding Process September 21, 2020 Publish Notice to Bidders, Advertise for Bids September 25, 2020 Publish Public Hearing Notice on Plans & Specs September 25, 2020 Public Hearing on Plans & Specs October 5, 2020 Receipt of Bid Proposals (Bid-Letting) October 22, 2020 Award Construction Contract November 2, 2020 Project Completion Date March 31, 2021 BUDGETIMPACT The project is bid as a whole to obtain economy of scale and to ensure the sequence of taking wells off line is carefully coordinated with one contractor and the operations staff without loss of production. The estimate of probable cost for the Dubuque Water Supply Well Repair and Rehabilitation Project 2020 (Wells 3, 6, and 8) is as follows: Description Estimate Construction Contract $170,000 Contingency (10%) $17,000 Construction Engineering & Inspection (10%) $18,700 Estimated Total Project Cost $205,700 FUNDING SOURCE Capital Improvement Project 7401415 is available to fund the project. The summary of available funds is: CIP NO. Fund Description Amount 7401415 Wells Rehabilitation $250,000 The available resource balance after the project is estimated to be $44,300. RECOMMENDATION I recommend that the City Council establish October 5, 2020 as the date for the public hearing and authorize the City Clerk to advertise bid proposals Dubuque Water Supply Well Repair and Rehabilitation Project 2020 (Wells 3, 6, and 8). cc: Jennifer Larson, Director of Finance and Budget Bret Stierman, Electrical Technician Rick Grothe, Maintenance Technician Prepared by Denise Blakeley-Ihriq. Water Department Manager Address: 901 Hawthorn St. Telephone: 563-589-4290 Return to: Kevin Firnstahl, City Clerk Address: City Hall- 50 W. 13th St Telephone: (563) 589-4100 RESOLUTION NO. 299-20 DUBUQUE WATER SUPPLY WELL REPAIR AND REHABILITATION PROJECT 2020 (WELLS 3, 6, AND 8) PRELIMINARY APPROVAL OF PLANS, SPECIFICATIONS, FORM OF CONTRACT, AND ESTIMATED COST; SETTING DATE OF PUBLIC HEARING ON PLANS, SPECIFICATIONS, FORM OF CONTRACT, AND ESTIMATED COST; AND ORDERING THE ADVERTISEMENT FOR BIDS NOW THEREFORE, BE IT RESOLVED BY THE CITY COUNCIL OF THE CITY OF DUBUQUE, IOWA THAT: Section 1. The proposed plans, specifications, form of contract and estimated cost for the Dubuque Water Supply Well Repair and Rehabilitation Project 2020 (Wells 3, 6, and 8) in the amount of $205,700, are hereby approved and ordered filed in the office of the City Clerk for public inspection. Section 2. A public hearing will be held on the 5th day of October 2020, at 6:30 p.m. in the Historic Federal Building Council Chambers (and/or by virtual means), 350 W. 6th Street, Dubuque, Iowa, at which time interested persons may appear and be heard for or against the proposed plans and specifications, form of contract and estimated cost of said Project, and the City Clerk be and is hereby directed to cause the attached notice of the time and place of such hearing to be published in a newspaper having general circulation in the City of Dubuque, Iowa, which notice shall be published not less than four days nor more than twenty days prior to the date of such hearing. At the hearing, any interested person may appear and file objections to the proposed plans, specifications, form of contract, or estimated cost of the Project. Section 3. The Dubuque Water Supply Well Repair and Rehabilitation Project 2020 (Wells 3, 6, and 8) is hereby ordered to be advertised for bids for construction. Section 4. The amount of the security to accompany each bid shall be in an amount which shall conform to the provisions of the Notice to Bidders hereby approved. Section 5. The Water Department Manager is hereby directed to advertise for bids for the construction of the improvements herein provided, by publishing the Notice to Bidders to be published on the City of Dubuque website and a contractor plan room service with statewide circulation, which notice shall be published not less than thirteen but not more than forty-five days before the date for filing bids before 2:00 p.m. on the 22nd day of October 2020. Bids shall be opened and read by the City Clerk at said time and will be submitted to the City Council for final action at 6:30 p.m. on the 2nd day of November 2020, in the Historic Federal Building Council Chambers (and/or by virtual means), 350 West 6th Street, Dubuque, Iowa. Passed, adopted and approved this 21st day of September 2020. Roy D. Buol, Mayor Attest: Ke in S. Firnstahl, City Ierk NOTICE OF PUBLIC HEARING ON PLANS, SPECIFICATIONS, FORM OF CONTRACT, AND ESTIMATED COST FOR DUBUQUE WATER SUPPLY WELL REPAIR AND REHABILITATION PROJECT 2020 (WELLS 3, 6, AND 8) NOTICE IS HEREBY GIVEN: The City Council of the City of Dubuque, lowa will hold a public hearing on the proposed plans, specifications, form of contract and estimated cost for the Dubuque Water Supply Well Repair and Rehabilitation Project 2020 (Wells 3, 6, and 8), in accordance with the provisions of Chapter 26, Code of lowa, at 6:30 p.m., on the 5t" day of October 2020, in the Historic Federal Building Council Chambers (and/or by virtual means), 350 West 6t" Street, Dubuque, lowa. Said proposed plans, specifications, form of contract and estimated cost are now on file in the office of the City Clerk. At said hearing any interested person may appear and file objections thereto. The scope of the Project is as follows: Project involves the repair and rehabilitation of three municipal drinking water supply wells (Wells 3, 6, and 8). Copies of supporting documents for the public hearing are on file in the City Clerk's Office, City Hall, 50 W. 13t" St., Dubuque, lowa, and may be viewed during normal working hours. Agendas can be accessed at https://www.cityofdubuque.org/Aqendas. Written comments regarding the above public hearing should be submitted to the City Clerk's Office, 50 W. 13th St., Dubuque, IA 52001, ctyclerk cityofdubuque.org, on or before said time of public hearing. At said time and place of public hearings all interested citizens and parties will be given an opportunity to be heard for or against said proposal. Individuals with limited English proficiency, vision, hearing or speech impairments or requiring special assistance should contact the City Clerk's Office at (563) 589-4100, TDD/TTY (563) 690-6678, ctyclerk cityofdubuque.orq as soon as feasible. Deaf or hard-of-hearing individuals can use Relay lowa by dialing 711 or (800) 735-2942. In the event that a meeting at the Historic Federal Building location is not possible as a result of the COVID-19 pandemic, instructions for a virtual meeting and public input will be posted on the meeting agenda on Friday, October 2, 2020 at https://www.citvofdubuque.orq/aqendas. Published by order of the City Council given on the _ day of 2020. Kevin S. Firnstahl, CMC, City Clerk