Slide 3 of 3

The determination of the study period was based on the available streamflow and diversion data/records. Based on the review of available data, and input from the BAG, a 28-year study period was selected from 1971 to 1998. This chart illustrates the period of record for several streamflow gages within the Bear River Basin. Records associated with items 3, 15 and 25 which reflect the gages noted above (Gage 11500, 20300, and 39500 respectively). These gages all have continuous records within the selected study period. Several of the main stem gages will be utilized as calibration gages for the model development (to verify assumptions made to simplify the model). Where records are not continuous, analytical procedures will be utilized to create a continuous data set.

The diversion records were also reviewed and evaluated. Complete and continuous diversion data were available for all years beginning with 1971. This was another reason that the study period was selected from 1971 to 1995. Item number 27 in the chart reflects the diversion data.

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