LIBBY PROJECT INFLOW FORECAST, KAF 1998 ========================================================================================= FORECAST DATE 1 Jan 1 Feb 1 Mar 1 Apr 1 May 1 Jun ========================================================================================= FORECAST'S KAF Apr-Aug runoff, Fort Steele 3219 3332 3019 3097 3027 3600 Apr-Aug runoff, Libby Local 2351 2348 2036 2133 2094 2589 ----- ----- ----- ----- ----- ----- Apr-Aug runoff, Libby inflow 5570 5680 5054 5230 5121 6190 Apr-Aug norm, 6376.8, 1961-19 87.3% 89.1% 79.3% 82.0% 80.3% 97.1% Apr-Jul runoff 5048 5148 4580 4739 4641 5622 May-Jul runoff 4630 4722 4202 4347 4161 5131 Jan-Jul runoff 5668 5778 5210 5383 5284 6255 Date-Jul runoff 5668 5568 4809 4750 4160 2958 Date-Jul standard error 1759 1202 1096 1058 941 729 Date-Jul confidence limit, 1 3909 4366 3713 3692 3219 2229 Date-Jul 5% confidence 7426 6771 5904 5808 5101 3687 ========================================================================================= FLOOD CONTROL, DRAFT BY: 31 Jan 28 Feb 15 Mar 31 Mar 30 Apr lookback required draft, KAF 2315 2678 1921 2148 2007 required elevation, FT 2402.0 2390.5 2413.2 2406.9 2410.8 ========================================================================================================= FORECAST COMPONENT SUMMARY FRO WP SWE SP SP+NS INT TOTAL FORT STEELE, B.C., (FS) 1.807 65.19 98.6 28.26 42.02 inches=(fro(1.309)+wp(0.068)+swe(0.067)+sp(0.167))-5.114 inches 2.365 4.433 6.606 7.017-5.11415.308 inches*235.2=kaf ............................................... 3600 LIBBY LOCAL, (LL) 1.443 49.88 74.2 26.00 37.93 inches=(fro(0.921)+wp(0.086)+swe(0.046)+sp(0.152))-4.183 inches 1.329 4.290 3.411 5.765-4.18310.612 inches*244.0=kaf ............................................... 2589 TERM DEFINITION fall runoff is FRO winter precip is WP normal subsequent is NS snow water equivelant is SWE spring precip(weighted) is SP equation constant, or, y-INTERCEPT is INT ========================================================================================= OBSERVED DATA, usage, FS=Fort Steele, LL=Libby Local WINTER PRECIP(WP), inches Oct Nov Dec Jan Feb Mar Banff FS 0.50 0.19 1.27 0.61 0.13 1.33 Brisco FS 1.02 1.06 0.67 2.68 0.12 1.91 Fernie LL 6.53 1.56 1.70 3.70 1.40 5.79 Kaslo FS 4.89 2.02 1.74 4.83 1.35 3.52 Rogers Pass FS 7.30 6.35 7.17 8.03 2.74 3.76 Fortine LL 1.75 0.60 0.41 0.74 0.27 1.03 Libby RS LL 2.39 1.28 0.54 2.24 0.47 1.18 Bonners Ferry LL 2.77 0.89 0.82 2.11 0.79 1.27 Polebridge LL 2.19 0.90 0.85 2.27 0.10 1.34 SNOW WATER EQUILVENT(SWE), inches 31 DEC 31 JAN 28 FEB 31 MAR Glacier FS 12.6 18.1 20.7 23.4 Kicking Horse FS 4.5 5.8 9.1 10.5 Kimberly LL 0.6 1.4 2.1 3.0 Marble Canyon FS 5.0 8.5 9.8 10.9 Mirror Lake FS 3.7 6.3 7.9 9.7 Morrissey Ridge FS & LL*.5 7.8 16.4 18.6 26.1 New Fernie FS & LL 2.0 7.5 8.4 9.4 Sullivan Mine FS & LL 1.1 5.9 6.5 8.6 Red Mtn. LL 5.3 8.0 9.7 13.7 Weisel Divide LL 9.7 19.2 22.2 26.4 FALL RUNOFF(FRO), kaf Oct Nov SUM Fort Steele f=235.2 283 142 425 Libby local f=244.0 199 153 352 f=, is to convert from basin inches to acre feet(x), or acre feet to basin inches(/). LIBBY INFLOW, kaf Oct Nov Dec Jan Feb Mar Apr May 482 295 232 210 191 232 491 2173 SPRING PRECIP(SP), inches Apr May Brisco FS 0.65 2.11 Creston FS 1.04 7.09 Kaslo FS & LL 1.36 3.07 Wasa FS 0.91 4.46 Fortine LL 1.01 6.76 Porthill FS & LL 0.94 6.63 Whitefish LL 1.48 4.75 ========================================================================================= Previous fcsts have changed because some estimated precip has been replaced with observed. Questions? Russ Morrow, 503-808-3951 or Bruce Glabau, 503-808-3950