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b) It is recommended that HGL designation <br />methodology be confirmed or clarified before the <br />pressure zone attribution process begins. <br />Elevation Modeling, Allocation, and QA <br />IDM utilize a DEM or Google Earth or equivalent <br />provided by the City, in combination with the <br />WaterGEMS hydraulic model software to assign <br />elevations to junctions, tanks, valves, and pumps. <br />Careful attention will be given to assigning facilities <br />with ground elevations relative to the elevation of <br />possible SCADA remote sensors. <br />Quality Assurance Steps: Following elevation <br />assignments, 1 foot contours will be created within <br />WaterGEMS and visually Inspected for any elevation <br />'holes" or "spikes". Visual inspection will also include <br />comparisons of "dips" or "crests" which may differ <br />visually from the DEM provided. A query for <br />"JELEVATION ZERO", Junctions with blank or zero <br />elevations" will be utilized to apply a visual Inspection <br />through the domain manager of InfoWater. <br />Service Node Attribution <br />IDM will use pre - defined criteria to identify and <br />attribute which Junctions are to host water demands. <br />Large diameter pipes and facility locations are typical <br />criteria for isolating non - service junctions. Additional <br />care will be given to those junctions at pressure zone <br />boundaries, which may be delineated by actual <br />serviceability to -from the pressure zone, Large <br />customers will receive their own dedicated <br />attribution, demand, and pattern assignments. <br />Quality Assurance Steps: Queries to find <br />"JSERVICE NODE, Junctions with service demands" <br />will be applied and visually inspected via mapping and <br />database attributions. <br />Quality Assurance Steps: Total demand allocated to <br />the model will be summed to confirm that the total <br />demand Introduced by the meter layer equals the <br />total demand allocated as the model's base demand, <br />Development and Assignment of Boundary <br />Conditions <br />2. fmplerr <br />provided. Boundary conditions will Include: tank <br />levels, groundwater pumping levels, pump curves, <br />valve settings, turnout flows, and initial status. <br />Quality Assurance Steps: Following the initial <br />assignments of hydraulic boundary conditions, the <br />hydraulic model will be run to evaluate preliminary <br />hydraulic results relative to range of static pressures. <br />The hydraulic model will be run initially for a steady <br />state simulation, evaluating the initial status controls <br />prior to implementing simple controls for EPS. <br />Development and Assignment of Control Rules <br />IDM will export the WaterGEMS node control tables <br />and populate one table each for the maximum day <br />and minimum day calibration periods. This will <br />involve Identifying controlling node, type of control <br />(pressure, flow, time, etc,), control set points, and <br />possibly speed of pump if a VFD. Itils data will be <br />generated using SCADA data, operator input, and <br />hydraulic schematics provided prior to populating the <br />model. This data will be uploaded to the hydraulic <br />model within different data sets for each demand <br />condition and calibration period. <br />Recommendations and Assumptions: <br />a) IDM will seek to minimize the use of time based <br />controls wherever possible. IDM will seek to also <br />minimize the use of Programmable Logic Controls <br />(PLC) in WaterGEMS as simple controls within the <br />software are easier to access, edit, and manage. <br />If a PLC appears to be needed, IDM will propose <br />use of a double - simple control, applied to nodes <br />and pipes. it has been found that from a <br />management and a convergence perspective, this <br />solution proves more robust than exercising PLCs. <br />IDM has extensive experience with PLCs, and may <br />utilize this approach If the City prefers as well. <br />b) IDM will assign valves with PRV stations simple <br />controls. it has been found through extensive <br />experience with multi- pressure zoned, and <br />hydraulically complex systems that parallel PRVs <br />can create stability /convergence issues within the <br />model software. As such, IDM has developed a <br />IDM will establish a preliminary set of boundary robust set of initial status and simple controls <br />conditions for both maximum day and minimum day. specifically for parallel PRVs to apply to these <br />These boundary conditions will be developed using <br />SCADA data, operator Input, and hydraulic schematics <br />IDMIODELIN M <br />we can bs mare, toaettier. <br />2501-15 <br />