OCR Text |
Show Waddell and Fields- Model for Evaluating the Effects of Dikes on the Water and Salt Balance of Great Salt Lake 13 To Farmington Bay Waterfowl Management Area To Duck Club Diked Area To Great Salt Lake North Point Consolidated Canal 10172600 Below Cudahay Lane Table 4. Compilation of data showing net change of flow, in cubic feet per second, from State Highway 83 to the dike of the Bear River Migratory Bird Refuge. Middle branch of Brighton Canal Extension Dam 10170490 Figure 8. Schematic diagram showing relation of flows in lower Jordan River basin. includes the entire 1931- 73 base period ( table 6). Records for site 10118000 were used to extend the record near Corinne ( site 10126000) to the 1931- 73 base period. Other canals and drainage tributary to the Bear River that cross State Highway 83 ( site 10127110) were measured during the 1972- 74 water years. 1 This flow was then added to the flow of the Bear River near Corinne, giving the total flow across State Highway 83 ( table 13). The percentage of the total flow across State Highway 83 that was contributed by the tributaries and canals was computed for each month during the 1972- 74 water years and was found to average about 10 percent of the flow of the Bear River near Corinne. The 10- percent gain was then applied to the 1931- 71 estimates to provide a 1931- 73 estimate of the total flow across State Highway 83. To extend the record from State Highway 83 to the outflow point at the Bear River Migratory Bird Refuge dike, measurements were made during 1974 of flow changes from State Highway 83 to the dike ( table ' A water year is the 12- month period from October 1 through September 30, and it is designated by the calendar year in which it ends. Thus, the water year ending September 30, 1974, is called the " 1974 - water year." Date Total flow across State Highway 83 Two- day average ( rounded) Refuge dike Net gain(+) or loss(-) 3- 14- 74 3- 15 4,530 4,470 4,500 5,330 + 830 4- 11 4- 12 3,050 3,210 3,130 4,090 + 960 4- 25 4- 26 3,610 3,670 3,640 4,130 + 490 5- 9 5- 10 3,960 4,200 4,080 4,480 + 400 5- 23 5- 24 3,450 3,400 3,420 2,800 - 620 6- 6 6- 7 3,260 3,370 3,320 3,550 + 230 6- 20 6- 21 2,530 1.940 2,240 2.340 + 100 7- 4 7- 5 1,030 1,00( 1 1,020 626 - 394 7- 21 7- 22 1,130 1,090 1,110 122 - 988 8- 7 S- 8 733 926 830 598 - 232 8- 18 8- 19 723 451 587 644 + 58 9- 4 9- 5 1,030 794 912 549 - 363 9- 16 9- 17 9- 29 9- 30 10- 14- 74 10- 15 11- 3 11- 4 1,600 1,690 1.640 1,770 + 130 919 911 915 984 + 69 1,630 1,500 1,560 1,550 - 10 1,630 1,670 1,650 2,120 + 470 4 and fig. 7). Figure 7 shows the net change of flow from State Highway 83 to the dike of the Bear River Migratory Bird Refuge. Of the 16 measurements made during 1974, 6 indicated net losses. Most of these losses occurred during the warmer months when evaporation was high; conversely, gains generally occurred during the months when evaporation was low. These measurements are representative of 1974, but it is not known how well they relate to 1931- 73. In view of these uncertainties, an alternative method was used to estimate the net change from State Highway 83 to the refuge dike. |