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the closest pipeline, taking into account zone boundaries and transmission pipelines that may physically reside within one pressure zone but be providing service to another adjacent zone. The future land use designations developed in Task 4, and verified unit water demand factors developed in Task 4 will be used to allocate future demands to the model. TASK 6.4 CONDUCT FIELD TESTING PROGRAM AND CALIBRATE MODEL WY A proposes to conduct field hydrant testing and a special flow monitoring program at SFPUC turnouts using rented flow monitoring devices that can be installed at existing meter locations. The flow monitoring data will be used along with the hydrant test data for model calibration, for developing diurnal curves for the hydraulic model, and for establishing daily and hourly peaking factors for use in the system analysis. WY A will develop a hydrant testing calibration plan for City review. The plan will identify proposed hydrant test locations, proposed test protocols, model calibration target accuracies, and supplemental information from SCADA and the flow monitoring program required for model calibration. With the assistance of City field personnel, WY A will perform hydrant flow testing in selected areas of the existing system to determine/confirm the roughness coefficient (C-factors) used to calibrate the hydraulic model of the City water system. Based on discussions with City staff and WY A's knowledge of the system, up to 20 hydrants will be selected for flow testing; these tests will be performed by City staff, with WY A observing tests and providing initial direction for tests. Budgeting assumes up to two days of field assistance by WY A. WY A will evaluate the field data, and determine appropriate C-factors based on pipeline age, size and material. Budgeting assumes that City staff will have overall responsibility for testing, including operating/closing valves, dechlorinating flow, and conducting traffic control during these tests. Using hydrant test data and SCADA information, WY A will set up model scenarios for the hydrant flow tests. Model results will be compared with field results, and model C-values will be adjusted to match model results to field results. Where model results cannot be adjusted by selecting realistic C-values, possible reasons for discrepancies and future steps that could be taken to improve the calibration will be identified. TASK 6.5 DEVELOP AND INTEGRATE DIURNAL DEMAND PATTERN To be able to create an extended period simulation analysis of the City's system, diurnal water use patterns are required. According to City staff, booster pump stations have flow monitoring data available from SCADA, but SFPUC turnouts have totalizing meters that are read monthly. Therefore, it is possible to construct diurnal curves for smaller pumped zones, but not for the City Main Zone or other zones supplied directly from SFPUC turnouts. A special flow monitoring program is proposed for selected SFPUC turnouts, as discussed in Task 6.4. Pumped zones are typically smaller pressure zones supplying hilly areas, which tend to have predominantly residential use. The Main City Zone is the largest pressure zone within the system, and has a mix of commercial and residential use. In WY A's experience, smaller, more residential zones tend to exhibit larger diurnal usage variations due to residential water usage patterns. Larger pressure zones, such as the Main City Zone, exhibit flatter diurnal curves because the mix of users with different diurnal water use patterns. October 22, 2009 8