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The following supporting information supports the selection of the indicator stations, <br />based on the criteria defined above. <br />• The Cherry Creek near Franktown gage (06712000) was selected to represent <br />Water District 8. Diversions upstream from the Cherry Creek near Franktown <br />gage station for irrigation purposes are minimal and therefore considered <br />insignificant to the overall flow. <br />• The North Platte River near Northgate (06620000) was selected to represent <br />Water District 47, and to a lesser degree, Water Districts 48 and 76. This gage <br />includes effects from some upstream diversions, but is the only long-term gage in <br />the North Platte River basin. There are no gages with records spanning the study <br />period on the Laramie River (Water District 48) or on Sand Creek (Water District <br />76). <br />• The North Fork South Platte River below Geneva Creek at Grant (06706000), <br />which was replaced by the North Fork South Platte River at Grant, station <br />PLAGRACO in 1991, was selected to represent Water Districts 23, 80, and 9. <br />The location is 1.3 miles downstream of Roberts Tunnel; therefore, Roberts <br />Tunnel diversions were subtracted out of the overall flow to evaluate conditions at <br />this station without the influence of transbasin diversions. No other significant <br />diversions or storage influence this gage. <br />• The Middle Boulder Creek at Nederland gage (06725500) was selected to <br />represent Water Districts 5, 6, and 7. No significant diversions or storage <br />influence this gage. <br />• The Big Thompson River at Mouth of Canyon near Drake gage (06738000) was <br />selected to represent Water District 4. Water delivered from the Colorado-Big <br />Thompson project is re-diverted, along with some native inflow, above this gage. <br />However, the station is believed to provide adequate representation of overall <br />conditions within the basin. <br />• The Cache La Poudre River at Mouth of Canyon near Fort Collins (06752000) <br />was selected to represent Water District 3. This gage is affected by both storage <br />and transbasin diversions, however, it is the only long-term gage on the Poudre <br />River and, therefore, was considered in the analysis. <br />• The South Platte River at Julesburg (06764000) was selected to represent <br />conditions in the South Platte River before leaving the state of Colorado and <br />flowing into the state of Nebraska. This gage is strongly affected by transbasin <br />diversions, storage, and diversions for irrigation, and was included for comparison <br />only. <br />Each of the seven selected indicator stations was individually evaluated based on annual <br />streamflow and cumulative streamflow over the available period of record through water <br />year 2002. The purpose of the individual evaluation was to determine if the long term <br />average hydrology for the period of record was reflected in the selected study period and <br />that wet, dry, and average periods were evident in the streamgage data. <br />Annual streamflow was plotted for each indicator gage and the long-term average was <br />compared to the 1950 to 2002 average, an example of which is shown on Figure 2. As <br />Page 7 of 21 <br />