1. SWC Methodology - TWG February 19, 2015 Settlement Document Subject to I.R.E. 408

2. Update on Natural Flow Predictor Models

3. April 1 Models Considering using other forecasts Predictor models for all SWC members Relationship between Box Canyon and Blackfoot to Milner reach gains.

5. NRCSUSACOE/USBRAveraged NRCS/USACOE&USBR 200025%12%18% 20011%13%7% 200214%12%13% 20037%3%5% 2004-19%-13%-16% 200510% 200625%24% 20071%0%1% 2008-10%-12%-11% 2009-36%-26%-31% 2010-13%-20%-17% 2011-2%12%5% 20125%16%11% 201323%14%19% 20142%3% Average2%3% Standard Deviation18%15%16%

6. New TFCC April Natural Flow Predictor TFCC= 62.01 (Heise) +12,980(Box) – 609,600 Where: TFCC = TFCC natural flow supply from April to October; Hei = Heise natural flow forecast from April – July in (KAF); Box = Box Canyon total flow from November through March (KAF). Adjusted R 2 pSEDOFF-statistic 0.8664<0.00138,0102175.6

7. Current April Natural Flow Models SWC Member Equation (less one standard error) R2R2 A&By = 0.0092x - 19.7470.887 AFRD2y = 0.0742x - 141.140.8317 BIDy = 0.0344x - 2.58530.7964 Milnery = 0.0102x - 19.4120.9243 MIDy = 0.0484x + 2.71780.7896 NSCCy = 0.1562x - 53.0050.8952 TFCCy = 0.0658x + 626.370.5416 Where: y = Natural flow April – October for the SWC Member (AF); x = Heise Natural Flow (April 1 – July 31). USBR/ACOE Heise forecast is used in April. *To error on the side of the SWC, natural flow predictions are one standard error below regression line.

8. April 1 Predictor Models for other SWC Members Used the same variables that were used for TFCC model: – Heise – Box Canyon Found no model improvement for: – A&B – AFRD2 ? – Milner – All have late priority NF rights

9. SWC Member Water Right Priorities A&B1939 AFRD21921 BID1903, 1908, 1939 Milner1916, 1939, 1939 MID1903, 1908, 1939 NSCC1900, 1905, 1908, 1915, 1920 TFCC1900, 1915, 1939

10. Multilinear Regression Model : AFRD24to10 = HeiseAprtoJulKAF + Box11to3) Residuals: Min 1Q Median 3Q Max -64494 -22886 -6416 19101 64373 Coefficients: Estimate Std. Error t value Pr(>|t|) (Intercept) -435713.23 170094.89 -2.562 0.0182 * HeiseAprtoJulKAF 73.22 6.70 10.928 4.01e-10*** Box11to3 3317.91 1673.59 1.983 0.0607. --- Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1 Residual standard error: 37290 on 21 degrees of freedom Multiple R-squared: 0.8583,Adjusted R-squared: 0.8448 F-statistic: 63.58 on 2 and 21 DF, p-value: 1.233e-09 AFRD2 April 1 Models Linear Regression Model: AFRD24to10 = HeiseAprtoJulKAF Residuals: Min 1Q Median 3Q Max -69999 -23845 -1323 20850 79034 Coefficients: Estimate Std. Error t value Pr(>|t|) (Intercept) -1.014e+05 2.389e+04 -4.247 0.00033 *** HeiseAprtoJulKAF 7.418e+01 7.114e+00 10.428 5.6e-10 *** --- Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1 Residual standard error: 39700 on 22 degrees of freedom Multiple R-squared: 0.8317,Adjusted R-squared: 0.8241 F-statistic: 108.7 on 1 and 22 DF, p-value: 5.604e-10

11. April 1 MLR Predictor Models SWC Member Predictor Model Natural Flow Diversions (April – October) Adjusted R 2 SEF-Statistic BIDBID = 33.64(Heise) + 2570(Box) – 240,8000.854617,10068.61 MIDMID = 47.12(Heise) + 4302(Box) – 401,0000.878622,07084.22 NSCCNSCC = 154.19(Heise) + 6834.23(Box) – 677,9490.915155,950125 TFCCTFCC= 62.01 (Heise) +12,980(Box) – 609,600 0.866438,01075.6 Where: Heise is the total Heise natural flow from April – June in (KAF); Box = Box Canyon total flow from November through March (KAF).

12. Current April Natural Flow Models SWC Member Equation (less one standard error) R2R2 A&By = 0.0092x - 19.7470.887 AFRD2y = 0.0742x - 141.140.8317 BIDy = 0.0344x - 2.58530.7964 Milnery = 0.0102x - 19.4120.9243 MIDy = 0.0484x + 2.71780.7896 NSCCy = 0.1562x - 53.0050.8952 TFCCy = 0.0658x + 626.370.5416 Where: y = Natural flow April – October for the SWC Member (AF); x = Heise Natural Flow (April 1 – July 31). USBR/ACOE Heise forecast is used in April. *To error on the side of the SWC, natural flow predictions are one standard error below regression line.

13. Box Canyon Discussion

14. July 1 Models Two Oceans Plateau SWE – Consider using an earlier date to remove years with zeros Concerns over using Spring Creek data. – Consider using only metered data – Investigate using other indicators Tyhee (missing data 1995 – 2001) Wells Predict total natural flow in the Blackfoot to Milner reach then allocate by priority

15. Two Oceans Plateau Looked at June 1 and June 15. June 15 had better results than June 1. June 15 data set has 4 years with zero SWE July 1 data set has 13 years with zero SWE

16. July 1 MLR Predictor Models SWC Member Adjusted R 2 SEF-Statistic BIDOld 0.8672 New 0.828 12,810 14,580 51.06 37.9 MIDOld 0.8808 New 0.8438 17,490 20,020 57.63 42.42 NSCC0.9003 New 0.8593 39,820 47,300 70.22 47.83 TFCC0.8304 New 0.8511 31,240 29,270 38.54 44.83 Where: Heise is the total Heise natural flow from April – June in (KAF); SpringCreek is Spring Creek total flow from January - May (KAF); TwoOceans is the July 15 Snow Water Equivalent (in).

17. Spring Creek Alternatives