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The advancement of GIS mapping availability now provides <br />for an efficient means to construct and utilize water system <br />modeling technology. Seamless data import and export <br />allow computer models to be easily constructed with <br />available GIS data and then calibrated to industry standards. <br />Once constructed and calibrated, the water system model <br />will be a valuable tool for developing an understanding of <br />existing water system operations, evaluation of deficiencies <br />and analysis of potential improvements. <br />Data Collection and Model Assembly <br />A computer model of the water distribution system will be <br />developed using WaterCAD modeling software. The current <br />water distribution piping, elevated storage tanks, well pump <br />curves, and operational data will be incorporated into the model. <br />Historical water system pumping data and usage data <br />(from billing records) will be analyzed. This information <br />can be extracted from monthly water billing summaries <br />and assigned by address in the model. Furthermore, <br />existing pumping records will be analyzed to develop an <br />understanding of usage trends including Average day and <br />Max day use. Additional water distribution system data <br />(such as details related to facility operations) and mapping <br />information will need to be collected and incorporated in <br />the computer model as well. Elevations will be assigned to <br />the model using contour and elevation data, which is readily <br />available. Also, additional well, tower, pipe age, and pipe <br />material information will be collected and reviewed for use in <br />the model. Upon completion of this task, the complete water <br />system will be constructed within the modeling software and <br />ready to be modified and calibrated with field data. <br />Additional data incorporated into the model will include the <br />current system operational data, and other system facility <br />parameters necessary to provide for the construction of an <br />accurate hydraulic model. Model demands will be assigned <br />based on water pumping or billing records, as available, with <br />peak demand factors being based on historical water use <br />statistics for the City. <br />Calibration <br />Calibration testing will be conducted by SEH with assistance <br />from City staff. Potential flow testing locations will be <br />reviewed with City staff to ensure feasibility of the testing <br />plan. City staff will operate all hydrant valves. SEH will <br />provide testing equipment and collect pressure and flow <br />data during hydrant operation. It is expected that this task <br />will take up to two days. Because of the schedule for this <br />project and the time of year, SEH will want to flow test <br />the hydrants as soon as possible following the Notice to <br />Proceed. SEH will want to be complete with flow testing <br />before mid November 2019. <br />Calibration data will be utilized in a genetic algorithm <br />calibration module to optimize model parameters for <br />accuracy. The model will be calibrated to provide accuracy <br />within 5% of field testing results, meeting industry standards <br />for water distribution system computer Models. At the close <br />of the project, SEH will turn the water model over to the City, <br />for the City to use in the future. We will also be available to <br />assist with operation of the model as requested by the City. <br />Water System Model Analysis and Verification <br />Upon calibration of the water model, an analysis will be <br />performed to determine if there are any deficiencies in the <br />existing system with respect to pressure and/or available <br />fire flow. Average day demand, maximum day demand, peak <br />hour demand, and EPS scenarios will be run for the existing <br />distribution system. Current hydrant flow availability will also <br />be analyzed. The initial system analysis will be used to verify <br />that the model is producing appropriate results. <br />Future Water System Growth and <br />Plant Siting Verification <br />Upon calibration of the model, we will develop scenarios <br />within the model representing existing Average Day, Max Day <br />and Peak Hour Conditions. Using future growth areas and <br />population projections from the City's Comprehensive Plan, <br />SEH will then develop a conceptual skeleton of trunk mains <br />to support municipal water service. <br />This future plan will assist the Project Team in understanding <br />the effect of plant siting on future growth of the community <br />water system. A summary of the standard initial system <br />analysis will be provided in memo form and SEH will provide <br />the data files to the City for future modeling analyses. <br />Preliminary Design Report <br />For this phase of the project, SEH proposes to complete <br />preparation of a report that brings all of the pieces together. <br />As laid out in the City's Request for Proposals significant, <br />but certainly not all, elements of the report will include the <br />following: <br />Selection of Water Source(s) <br />SEH will utilize the results of our aquifer investigation and <br />water system modeling efforts to identify the preferred <br />source water to serve the Ramsey Water Treatment Plant. <br />This work will include a meeting with the MDH, incorporation <br />of findings from the Northwest Metro Regional Surface <br />Water Supply study and discussions with neighboring <br />communities to determine the feasibility of Mount <br />Simon/Hinckley groundwater, surface water, or system <br />interconnects as potential sources for Ramsey. <br />SHORT ELLIOTT HENDRICKSON INC. 7 <br />