31C - CUP - 2800 N MAIN STREET UNIT 3100

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Mr. Gregg Berwin June 9, 2014 Page 5 Model Calibration Methodolo Shared Parking, 2nd Edition defined national averages to be used for parking demand rates for various land uses and it suggested ranges of assumptions to be used for transit and internal capture. The methodology, however, stated that the best way to measure the demand at a particular project is to use local data to modify the national averages, so that they reflect local conditions. As the Project proposes to replace existing vacant retail space, a shared parking model can be prepared and calibrated to the actual conditions. Two key data sets were utilized in the model calibration: actual parking utilization data and the amount of existing active floor area. Parking Utilization Data. Parking utilization surveys were performed in May 2014 to evaluate the parking demand characteristics during the off -peak non - holiday period. These surveys were conducted during the peak periods of 11:00 AM to 3:00 PM on Wednesday, May 14, 2014 and 12:00 PM to 6:00 PM on Saturday, May 17, 2014. This parking utilization data formed the basis for the existing parking occupancy pattern used for model calibration purposes. The results of the surveys are provided in the Attachment. Existing Active Floor Area. The shared parking model utilizes floor area as the metric to generate parking demand for each land use. Therefore, an accurate inventory of occupied floor area, at the time of the utilization survey, is required for the calibration process. Based on an MPM unit inventory provided by Westfield, approximately 918,710 sf GLA of a total 1,127,836 sf GLA was active in MPM in May 2014. This represents a vacancy level of approximately 19 %. Table 1 summarizes the land use program at MPM in terms of existing and occupied floor area; these occupied floor areas were used to calibrate the parking demand in the model. The model was calibrated using the active floor area data in conjunction with the parking utilization data. The process of calibration begins with the input of the active land uses into the model and generating parking demand estimates, based on the ULI /ICSC database. The next steps involve adjustments to the model factors, in order to have the model mimic the observed parking occupancy pattern. The model adjustment factors are described below. Model Adjustment Factors This discussion explains the adjustment factors available for use in the shared parking model and describes the basis for the adjustment of these factors. Time of Day. The time of day factor is one of the key assumptions of the shared parking model. This factor reveals the hourly parking pattern of the analyzed land use; essentially, the peak demands are indicated by this factor. The research efforts of ULI /ICSC have yielded a comprehensive data set of time of day factors for multiple land uses. As the demand for each land use fluctuates over the course of the day, the ability to implement shared parking emerges. The time of day factors were adjusted to mimic the observed parking occupancy pattern at MPM. For the future land uses not in the ULI /ICSC database, the time of day factors were researched from the operating hours of similar facilities. 31 C -22