Loading...
HomeMy WebLinkAbout5.b. Rural Water System Update26 2875 145111 ` I W lei ROSEMOUNT, MINNFS()TA 5',f)(ift �' osen� oun 1 February 12, 1988 TO: Mayor Hoke Councilmembers: Napper Oxborough Walsh Wippermann FROM: Stephan Silk, Administrator/Clerk RE: Rural Water System Update Gentlemen; Attached you will find a letter from Gordon Kraus, Engineer for DeWild Grant, Richert and Associates Co., this is the firm designing the rural water system for the U & M. I believe the letter is quite clear as to the question before us and that is whether to consider the utilization of the water tower as the holding facility for the system or not. Staff's review of this proposal at this writing has been minimal and we will complete discussion and be prepared to discuss it at our meeting on Tuesday. At first blush we have only the concern about upkeep costs on the tower even if it is brought up to a quality maintenance condition level. Other issues I believe would have minimum concern. Though we don't wish to hold up this project it is possible we may not be prepared to recommend a position on it until our March lst meeting but on Tuesday we will attempt to come to a consensus on it. dck DeWild Grant Reckert & Associates Co. Architecture Engineering and Planning 315 First Avenue RECEIVED Rock Rapids, Iowa 5'1246 (712) 472-2531 February 8, 1988 FEB 111988 CLERK': OFFICE Mr. Raymond J. Jackson, P.E. CITY OF ROSEMOUNT Engineering and Architecture Room 100 Shops Building 319 15th Avenue SE University of Minnesota Minneapolis, MN 55455 City of Rosemount 2875 145th St. W. Rosemount, MN 55068 Attn: Steve Jilk, Administrator Re: Rosemount Rural Water System DGR Project No. 3776 Gentlemen: This is to request the approval of the City of Rosemount and the University of Minnesota of the concept I discussed individually with you last week. We feel there are distinct advantages to both the University and Rosemount to incorporate the existing University Research Center elevated tank into the proposed rural water system. This letter will detail these advantages and provide background information so that both parties can respond in a timely manner. In order to maintain the work schedule required to complete the construction of this project during the 1988 construction season, we need your response by Feb. 17. Background Information The project area is within the City Limits of the City of Rosemount, located in Dakota Co. The western portion of the City has developed into a high density housing area and has a water supply, distribution, and storage system relying on a -number of wells within that portion of the City. The eastern part of the City is predominantly rural in character with scattered home sites and farms which rely on individual wells finished in the< Prairie due Chien or Jordan aquifers. Because of chloroform contamination in approximately 27 of these wells it has been determined that a rural water supply system should be built by the University of Minnesota to serve as a replacement domestic water supply for the polluted wells. The system would be designed to allow for expansion to serve up to a total of 201 3460 West 38th Aveniee 1051 Off icfr Park Road 600 Sioux City I" ederat Plaza BIdq 1't'M F asr, 1401 5trofl' Denver, Colorado 00211 Wi,!;t Df=s Wines. Iowa 50265 Sioux City. If1wa i )1f11 'iwuy I , 1I7,. CiouLh Dakota 57104 (303) 458-0311 (515) 225-8346 17121277-3049 tEi05) 339-4157 February 8, 1988 Page Two City of Rosemount connections which may ultimately be affected by the pollution plume origination from the Research Center. The City of Coates has also requested service from the proposed system. After construction the system would be given to the City of Rosemount for operation and maintenance. Initial Plannin During the initial planning stages of the proposed rural water system, three alternative water sources were considered as follows: 1. Connection to the existing City of Rosemount system. 2. Construction of two new wells. 3. Utilize the existing Research Center water system. These alternatives were presented to the City of Rosemount and the second alternative, construction of two new wells, was selected. Planning proceeded based on this alternative. The initial design concept was to provide service to the initial 27 connections and up to 201 total connections utilizing a small hydropneumatic tank to balance peak flows with the well pumping capacity. Dakota Co. AVTI During the design development phase the City requested that the new facilities also serve the Dakota Co. AVTI This was a reasonable request since the relatively large water use of this facility would allow the City to spread their fixed operating cost over a larger water use amount and thus reduce the cost per 1,000 gallons of water to the rural customers and bring these costs down to the same range as presently experienced in the balance of the City water systema Because the new well and hydropneumatic tank facilities could not provide adequate flows for fire protection, it was suggested that the Research Center would continue providing fire protection by retaining the connection of their system to the exterior main and fire hydrants at the AVTI and that the new supply would serve the inside water needs of the facility. The effect of this would be to drastically reduce the amount of water supplied by the Research Center, leaving a small number of water using facilities within the Center. We anticipate that because of demand reductions due to this change, the Research Center elevated tank would have very little water turnover and will likely freeze during the winter unless recirculation and/or water heating facilities are constructed. Because fire protection will need to be provided to the AVTI, removing the tank from service is not a viable alternative unless a substitute facility is constructed. February 8, 1988 Page Three City of Rosemount The addition of the AVTI also had a significant effect on the well/hydropneumatic system planned as the rural water supply. Instead of a modestly sized hydropneumatic tank and well pump system, a tank of 7 feet in diameter by 19 feet long with two 40 horsepower well pumps would be required. Because of this, we have approached both the University and the City with the suggestion that the Research Center tank and connecting pipeline become a part of the proposed rural water system. Both parties have agreed to seriously consider this concept. The Universitv Research Center Water System The University Research Center elevated tank has a capacity of 50,000 gallons. It was constructed in 1941 as part of the Twin Cities Arsenal. The tank is part of a water distribution and supply system serving the Research Center as well as the Dakota Co. AVTI adjacent to the Research Center. The water supply consists of one primary and one standby well finished in the Prairie du Chien and the Jordan aquifers. Distribution is by cast iron mains, presumably constructed at the same time as the elevated tank. A 10" diameter cast iron main connects the Research Center system to the AVTI. Proposal Summary The proposed system would consist of two new wells and a control building on the old City Hall site with a connecting main to the existing Research Center system and the new rural users. Sensors in the Research Center elevated tank would transmit level information to the control building and well pumps would be automatically staged on and off to keep the elevated tank full. A complete preliminary design is currently being developed for these facilities and will be reviewed with the University and the City at a later date. There are a number of details that will need to be worked out in order to transfer ownership or control of the elevated tank from the University to the City. Some of these include the following: 1. Who will supply water to the Research Center facilities? We suggest that the City sell water to the Research Center at the existing City water rates. 2. What will happen to the existing Research Center wells? We suggest that they be inspected, and if they meet health and safety standards, the City accept ownership and then maintains them as a backup source only. February 8, 1988 Page Four City of Rosemount 3. What is the condition of the elevated tank? We suggest an inspection by a qualified engineering firm, determine a maintenance schedule, and complete initial maintenance by the University before transfer to the City. 4. What about the balance of the Research Center distribution pipeline not part of the connecting pipeline between the new water source and elevated tank? We see no reason for the City to own this. Because it may be needed to serve facilities at the Research Center, the University will probably need to continue maintaining these lines or contract with the City for this service. We recognize that other significant details need to be dealt with but ask that to expedite matters, agreement be reached in principle on the general concept by February 17 so that our design work can proceed. The general concept is that the City accepts ownership of the Research Center elevated tank and connecting main so that these facilities can become a part of the proposed rural water systema Additional information, such as the anticipated water needs of the new system, is enclosed with this letter or is available in your files. We are available to answer additional questions you may have and can attend meetings at the University or City if you feel this might be helpful. To illustrate the importance of a timely decision, we also include a copy of our work schedule dated January 6, 1988. You will note that we had anticipated starting January or early February but cannot proceed with this phase until this matter is settled. A new schedule is being developed based on a determination of this matter by February 17 and will move bid letting into May or June with construction start in June or July. Additional delays will jeopardize the completion of the project this construction season. We look forward to your response. Sincerely, DEWILD GRANT RECKERT & AS CIATES COMPANY 1.� Gordon B. Krause, P.E. Project Manager GBK:kld cc: Fay Thompson Mark Longson ROSEMOUNT RURAL WATER ESTIMATED WATER NEEDS October 1987 (Revised February 1988) Average Day Peak Day (gallons) (gallons) PRESENT NEEDS Rural (27 connections) 4,000 11,000 AVTI 32,000 81,000_ Coates 12,000 31,000 Water loss (20%) 10,000 25.000 Total 58,000 148,000 FUTURE NEEDS Rural (201 connections) 30,000 75,000 AVTI 32,000 81,000 Coates 12,000 31,000 Water loss (20%) 15.000 37,000 Total 89,000 224,000 Rosemount Rural Water System Project No. 3776 Project Work Plan 1/6/88 Revised" Task No. Responsible Target Task Party Date A. Preliminary 1. Determine, service locations DELTA 1/7 2. Determine design water needs DGR 1/15 3. Determine location of wells DELTA 1/7 B. Water Source Design 1. Site survey D EI -7- 4 -DGR— 1/22 2. Select design alternative hydropneumatic storage or variable speed pumping DGR 1/15 3. Subcontract architectural, electrical, and mechanical services and initiate work DGR 1/22 4. Size and select equipment DGR 1/29 5. Contact electrical power supplier and request service DGR 2/5 6. Construct/test pump.pilot well DELTA 1/29- 7. Construct/test pump production well DELTA 2/26 8. Soils investigation DGR 1/29 C. Pipeline Design: 1. Select pipeline route DGR 1/15 2. Size and class pipeline DGR 1/29 3. Locate meter and service line %?_ 1/22 4. Locate valves and appurtenances DGR 1/29 Task No. Responsible Target Task Party Date D. Drawings and Specifications 1. Obtain aerial photography DGR 1/22 2. Draft mapping DGR 1/29 3. Develop floor plan pump house DGR 1/29 4. Complete water source civil drawings I DGR 2/19 5. Receive First Draft A and M&E Drawings DGR 2/19 6. Prepare quantity takeoff pipeline DGR 2/5 7. Assemble contract doe's DGR 2/19 8. First Draft Civil Spec's DGR 2/19 9. Receive First Draft A and ME Specs. DGR 2/19 10. Assemble First Draft and Cost Estimate of complete Drawings and Specs. DGR 2/22 11. Final Draft and Cost Estimate Drawings and Spec's. DGR 3/7 E. Permits and Right -of -Way 1. Apply for county, R.O.W. DGR 2/12 2. Apply for state R.O.W, DGR 2/12 3. Apply for RR R.O.W. DGR 2/5 4. contact existing utilities DGR 2/5 5. Contact rural users DELTA 1/22 M Task No. Responsible Target Task Party Date F. Reviews and Approvals: 1. Preliminary design conference with Rosemount 'DGR 1/14 2. Review of First Draft, Delta, Rosemount, U. of M. DGR 2/26 3. Review of Final Draft, Delta, Rosemount, U. of M. DGR" 3/11 4. Dept. of Health Review and Approval DGR 3/25 5. Authorize Advertisement for Bids U. of M. 4/1