The URL can be used to link to this page

Home My WebLink AboutSUS258UNIVERSITY OF ALASKA NICTIC EHVIRONM ErH J\1 IN ~g HJA~11 ~ AND DATJl S Er H LA 707 A 5 ff<.f:fT SUBJECT MEMORANDUM ---===== Dr . John Sizer Lower Susitna River Mo •·1~t.ol o gy -----------------~---------..-------------- FROM OATE i r-r,QJFCT NO. Steve Bredthauer 2 <!1 -84 352363 I ========-=-=====-=-==---=-=-=-=-=-==-::;::.=-=-=-=:!:==========· .. Representatives of R&M Consultants, Harza-Ebasco, and AEIDC met on December 21, 1983, to discuss a morphological classification system for the Susitnd River below the Chulitna River confluence . The lower Susitna Rive,. was broken into 5 segments, based on river morphology and hyd ro logy . The segments are described below and delinea ted on the encl:.s t:d river bluelines. ~egn •c nt I : HM !'18 ~' to k.v'! 7~ ·r h 's segment extends from 11 .~ Chulitna Rive :· confluence (Sheet 2': -:lo•v !-st1 ·eam to the head of the. side-channel complex jL•st. upstre<m~ ... Ol Montana Creek (Sheet 6). The river is braided, with the main channl-1 rr~eandering through a wide g 1 avel floodplain . Large expar1ses of S!rave! bars are expo~~d at low flow s. The channel is constricted to a single c:hannel at the Parks Highway Bridge (RM 83.8). Significant tributaries in this segment include Birch Creek, Trapper Cr·eek , Sunshine Creek, P.abideux Creek, and Whitefish Slough . A total of six side-channel comp lexes were identified . Segmer t II : RM 78 to RM 51 A Th1s sE-gment extent's f •·om thE" sicle-channel abovl' ~'fontana Creek (Sheet 6 ) to t hE> head of D€:!ta Islands (Sh ~c t 13) \•,here t l,e rive r splits into iwv m3in c hannels . The morpho lo gy in th is rear:h ;s c ·)1 11pl~ ... with " t<.-tal of 9 side -channel complexes along ~h~ edge of the river, and another 2 side-channel complexes i n large is:an J gro t.~s i ·-: , ' _; . ..::,<ii1r.c = Sig11ifi t;ant tribut:ar·ies in this segment inciL-de Mon tana Creek , Goose Creek , Sheep Creek, and the Kashwitna Rivar. . -~.-=:-.:.·.~-~:::-.:. .. -=~·. ··==-= February 21 , 1984 Bizer Memo Page 2 Segment Ill : RM 51 to RM 42. 5 This segment encompasses the Delta Islands reach (Sheets 13-16), where two main channels exist, one on the east and one on the west . A total of five si c annel complexes exist in this segment, with a major complex betwe c:n the two main channels . The segment ends where the two main channels rejoin. Significant tributaries in this segment include Little Willow Creek and Willow Creek . Segment IV: RM 42.5 to RM 28.5 This segment extends from the lower end of the Delta Island (Sheet 16) to the confluence with the Yentna River (Sheet 20). The reach is characterized by a braided pattern, with seven side-channel complexes . The Desh ka River enters the upper end of this reach . Kroto Slough branches off from this segment , and extends to the Yentna River. Segment V : RM 28.5 to RM 0 This segment extends from the Yentna River confluence to Cook Inlet. The Yentna River contributes about 40 percent of the flow at the mouth of the Susitna River . The segment is primarily a split-channel configuration down to RM 19, the head of Alexander Slough . The Susitna River has 2 channels from RM 19 to Cook Inlet, with the main channel on the east side . The west channel is primarily an overflow channel. Its upper section dewaters at low flow , while the lower segment is fed by Alexander Creek . Other tributaries entering this segment include Anderson Creek and Fish Creek. February 21, 1984 Bizer Memo Page 3 HABITAT TYPES Within the segments, four major morphological classifications have been identified which roughly correspond to habitat types . Mainstem Channel The mainstem channel is that portion of the river floodplain between the vegetated boundaries, including the wide gravel floodplain and isolated vegetated islands in mid-channel. Two subclassifications exist: 1) Main stem river, consisting of the thalweg channel and major subchannels . 2) Alluvial island complexes, which are areas of broad gravel islands with numerous subchannels which dewater as flow decreases . These subclassifications have not been separated while digitizing the wetted surface areas, but is would be possible to determine the areas relatively quickly. Side-Channel Complex The side-channel complexes are groups of side-channels flowing through vegetated islands . These are normally along the edge of the ma i n stem river, but may also include areas in the middle of the river, such as H1e Delta Islands . Twc subclassifications exist: 1) Lateral side-channel, which is the outside channel of the complex, closest to the edge of the floodplain. This channel collects any groundwater seepage or tributary flow from the river banks, so usually will not completely dewater, even when its upstream ber·m is not breached. February 21, 1984 Bizer Memo Page 4 2) Medial side-channels are the over·flow side -channels between the mainstem and the lateral side -channel . These side-channels dewater as main stem flow decr·eases . Sloughs Sloughs are simple, regular channels which are generally overtO>pped only at high fl o ws . They are differentiated from side-channel complexes by the fact that sloughs are an isolated channel , not f ed by a series of medial side-channels. Tributary Mouths Tributary mouths cover the area between the downstream extent of a tributary plume and the upstream effect of backwater . The area is variable, and depends both on the flow of the tributary and the mainstem stage. The length of the tributary pl u a,le ffidy' shar·ply increase when the tributary flows into a side-channel in which the upper end is no longer breached. PROCEDURE The purpose of this study was to prov ide a "first-cut"' delineation of changes in habitat area due to changes in flow of the Susitna River b e low Talkeetna . This study is not intended to be definitive, but will ser·ve as a guide to determine those segme nts o f the lower river which require further study. Aerial photography of the Susitna River from Cook Inlet to the Chulitna River confluence was obtained for the following four dates and flows: February 21, 1984 Bizer Memo Page 5 Date Flow, Susitna River at Sunshine 8-27-83 56,500 cfs 9-6-83 37,500 cfs 9-16 -83 22,000 cfs 10-25-83 13,600 cfs Remarks Typical July-August flow duri n g project operation . Transitional September flow during project operation. Upper bound of winter flow during project operation. Lower bound of winter flow during project oper<J l.• An aerial photo mosaic of each flight was made for segments I through IV . The mainstem, side-channel complexes, and sloughs were delineated for each segment . Segment V was not included, as it is felt that the flow flow from the Yentna River masks any changes in habitat area caused by project operation, and because tidal influence extends up to RM 20 . The wetted area of each morphological type was determined by planimetering the total area of each subsegment (mainstem or side-channel complex), then planimetering the area of e ach island and gravel bar within the subsegment . The area of the islands and bars was then subtracted from the total area of the subsegment, leaving the wetted area . To obtain the above areas, the subsegment boundaries were traced onto mylar from the aer·ial photo mosaics. Each island and gravel bar boundary was then traced, and the island numbered. Only wetted channels which extended through an island complex were delineated although backwater February 21 , 1984 Bizer Mem o Page 6 areas were included . Isolated pockets of water left when the water level dropped were not planimetered, as these were not considered usable habitat . All area were dig itized on an HP-9845 computer . The areas were delineated 2-4 times, and the average value used . The available photography has a nominal scale of 1 inch = 2 ,000 feet. However, there are minor d ifferences in scale from photo-to-photo and between each photo date . Th is loss of scale is caused by a number of factors , including wind and terra i n relief , and can not be accurately quantified . To acc ount for the differences in scale between flights , the total areas of each subsegment were compared to the corresponding total areas for th e flight on September 16, 1983 , whi c h is the fl ight from which the enclosed bluelines were prepared. The ratios of areas are shown in Table 1 . The differences i n total a r ea were generally in the range of t100o. The larger differences usually occurred in the smaller subsegments . The flights were unco ntrolled , with no pho topanels or surveyed sections available f o r determining scale f o r each segment . Co ns e:(,,,. n tl";, t h e t~r e<ts determined for the September 16, 1983 flight ha v e been assumed to be the base areas. All other digiti zed areas were adj usted to the September 16 scale by dividing by the correction ratios shown in Table 1 . RESULTS The changes in wetted surface area for mainstem and side-channel complexes are shown in Table 2, a nd are plotted on Figures 1 -9. The p ercent wetted a rea for e ach subsegme nt is the total wetted area divided by the t o tal area o f the sub segment (includ ing the vegetated areas ). Consequently, each s u bseg ment will have a differen t maximum percent wetted area , which is determ ined at bankfull flows when all gravel bars are covered . February 21, 19 84 Bizer Memo Page 7 The estimated lengths of tributary mouth habitats are shown in Table 3 . The upper ends of the backwater effects in the tributaries were estimated during aerial overflights within a day of the date the aerial pho tography was obtained . The downstream ends of the tributary plumes were estimated from the 1 inch = 2,000 feet photography . When a tributary flows into a lateral side-channel, the downstream extent of the tributary plume may extend a significantly longer distance downstream at low flows than at high flows . When the upper end of the lateral side-channel is not breached by mainstem flow, the characteri stics of the tributary dominate for a much longer distance downstream. cc : L. w. D . B . w. T . B . D. c . L. SB :mb sl /q Gilbertson , Harza-Ebasco Dyok, Harza-Ebasco Martin , Harza-Ebasco Wilson, AEIDC Trihey Trent, ADF&G Barrett, ADF&G Schmidt, ADF&G Estes, ADF&G Moulton , Woodward-Clyde s9 /t1 SEGMENT Main I sc 1-1 sc 1-2 sc 1-3 sc 1-4 sc 1-5 sc 1·6 TOTAL I Ma i n II sc 11 -1 sc 11-2 sc 11-3 sc 11-4 sc 11 -5 sc 11 -6 sc 11-7 sc 11-8 sc 11-9 sc 11-10 sc 11-11 TOTAL II TABLE 1 COMPARISON OF DIGITIZED AREAS ON LOWER SUSITNA MOSAICS (Digitized Total Area for date) TOTAL AREA TOTAL AREA (Digitized Total Area for 9-16-83) (acres) 6 (1 0 sq .ft.) 8-27-83 9 -6-83 10-25-83 9-16-83 9 -16-83 .987 1.002 1 .058 7,434 .2 324 1 .023 1 .026 1 .057 107 .4 4.68 .952 1.005 1 .058 746.5 32.5 1 .322 1 .037 1 .036 158 .6 6 .91 1 .262 1 .134 .960 31.7 1.38 .992 1.004 1.060 1 ,203.9 52.4 1.016 .990 1 .044 182.7 l. 96 .991 1.003 1.057 9 ,866.0 430 .943 .£76 1.036 10 ,442.0 455 1 .001 1.048 1 .063 238 .5 10.4 .937 .982 1 .032 665 .6 29 .0 .958 1 .019 1.025 326 .4 14.2 .955 1 .032 1 .063 1, 295 .9 56 .4 .912 .989 1.052 391.4 17.0 .966 1 .018 1 .047 3 ,586.1 156 1 .008 1 .052 1 .073 142 .1 6.19 .960 1.024 1 .058 1,246.1 54 .3 .989 .962 1 .049 150 .7 6 .56 .900 .952 1 .018 106 .3 4 .63 1 .015 .994 1 .047 4 ,851 .7 21 1 .963 .994 1.043 23,44 2.9 1021 s9 /t2 TABLE 1 (cont') COMPARISON OF DIGITIZED AREAS ON LOWER SUSITNA MOSAICS SEGMENT (Digitized Total Area for date) TOTAL AREA TOTAL AREA (Di gitized Total Area for 9-16 -83) (acres) 6 ( 10 sq. ft .) 8-27-83 9-6-83 10-25-83 9-16-83 9-16-83 Main Ill .974 .980 1.020 2 ,982 .4 130 sc 111-1 .980 .974 1 .022 929 .7 40.5 sc 111-2 .93 4 .991 1 .046 1,810 .5 78 .9 sc 111 -3 .977 .982 1 .059 6 ,647.0 290 sc 111 -4 .952 1 . 014 1 .076 522 .0 22.7 sc 111-5 .981 .991 1 .039 189 .8 8 .27 TOTAL Ill .970 .983 1 .046 13 ,081 .4 570 Main IV .974 1 .006 1 .052 3 ,373.2 147 sc IV-1 .979 .997 1 .039 426 .6 18 .6 sc IV-2 1 .079 1.045 1.017 164.0 7 .14 sc IV -3 .969 1.005 1 .038 1,276.5 55.6 sc IV-4 1.011 1 .009 1.061 727 .4 31 .7 sc IV-5 .926 1 .012 1 .015 69 .4 3 .02 sc IV-6 .9 78 .985 1.0 62 1,953.6 85 .1 sc IV-7 .891 1 .017 1.043 60.4 2 .63 TOTAL IV .979 1 .002 1 .051 8 ,051.9 351 59/ttl Date Flow(cfs) @ Sunshine SubsegrJent Mainstem 1 sc 1-1 (3) sc 1-2 sc 1-3 sc: 1-4 sc 1-5 sc 1-6 TOTAL SC Mainstem II sc 11-1 sc 11-2 sc 11-3 sc 11-4 sc 11-5 sc 11-6 sc 11-7 sc 11-8 sc 11-9 SC I 1-10 sc 11-11 TOTAL SC II 8-27-83 56,500 W. S.A. ( 1) 6 ( 10 sq ft) 203 0.82 3.83 2.76 0.42 14 1.6'/ 23.5 292 1. 16 6.33 3.20 12. 1 6.94 42.8 1. 74 13.5 0.74 1. 50 33. 1 123 Per·cent. of Sub segment Are<t ( 2) 62.8 17.3 11.8 lill.O 3n.2 26.7 20.9 22.2 611,2 11.2 21.8 2?.5 21. II 40.7 27.4 28.1 211.9 11.3 32.5 15.7 21.7 1) Wetted Surface Area W.S.A. 6 TABLE 2 CHANGES IN WETTED SURFACE AREA WITH fLOW LOWER SUSITNA RIVER 9-6-83 37.500 W.S.A. 6 9-i6-83 22,000 (10 sq ft) Percent of Sub segment An~a ( 10 sq ft) Perceut of Sub segment Area 156 48.2 123 38. 1 0.67 14.1 0.411 9.3 3. 31 10.2 2.47 1.6 ?.21 32.9 1. 63 23.6 0.40 28.6 0.111 29.9 11.5 21.9 8.47 16.2 1.29 16.2 1.14 14.3 19.4 18.3 14.6 13.8 229 50.3 199 43.8 1.16 11.2 0.58 5.6 4.27 14.7 3. 12 10.8 2.38 16.8 2.39 16.8 3.54 6.3 3.69 6.5 4.77 28.0 4.20 211.6 32.1 20.5 27. 1 H.3 0.63 10.2 0.51 8.~ 10. 1 18.7 9.25 17.0 0. 19 3.0 0.00 0.0 1. 29 21.9 1. 25 27.0 18. 1 8.6 16.8 7.9 78.5 13.~ 68.9 12.2 2) (Wetted surface area/Total subsegment area) x 100 3) SC indicates side-channel complex W.S.A. 6 10-25-83 13,600 ( 10 sq ft.) Percent of Sub segment Area 110 34. 1 0.46 9.8 2.52 '(, 8 1. 14 16.6 0. 37 26.~ 6.84 13.0 0.55 6.9 11.9 11.2 160 35.2 0.25 2.4 1. 41 II. 9 0.79 5.5 2.59 II, 6 2.13 12.5 11.9 '(, 6 0. 36 5.8 5.(18 10.8 0.00 0.0 0.59 12.8 6.84 3.2 32.7 5.8 S9/tt2 Date Flo\oi(CfS) @ Sunshine Sub segment Ma instem Ill SC I I 1-1 ( 3) sc 111-2 sc 111-3 sc 111-11 sc 111-5 TOlAL SC II I Mainstelll IV SC IV-1 SC IV-2 SC IV-3 SC IV-4 SC IV-5 SC IV-6 SC IV-7 TOTAL SC IV ,. 8-27-83 56,500 W. S.A. ( 1) 6 (10 sq ft) 91.9 11.4 14.1 46.3 7.23 2.75 81.8 103 2.94 2.32 12.6 8.08 0.82 26.8 0.77 54.3 Pen;ent of Subsec,u1ent Area i2l 70.7 28.1 17.9 16.0 31.8 33.3 18.6 69.8 15.8 32.5 22.6 25.5 2 (. 1 31.5 29. 1 26.7 1) Wetted surface Area W.S.A. 6 TABLE 2 ( cont' ) CHANGES IN WETTED SURFACE AREA WITH FLOW LOWER SUSITNA RIVER 9-6-83 37,500 W.S.A. 6 9-16-83 22,000 ( 10 sq ft l Percent of Sub segment Area (10 sq ft) Percent of Sub segment Area 74.7 57.5 61.9 47.7 10.4 25.6 -,.54 18.6 11. 5 14.6 6.91 8.8 38.2 13.2 27.6 9.5 5.34 23.5 3.87 17.0 0.57 6.9 0.47 5.7 66.0 15.0 46.4 10.5 87.5 59.5 75.0 51. 1 1. 52 8.2 1.05 5.6 1. 72 24.1 1. 31 18.3 10.5 18.9 8. 16 14.7 6.64 20.9 4.76 15.0 0.74 24.4 0.38 12.4 22.0 25.9 17.2 20.2 0.66 25.2 0.36 13.7 43.8 21.5 33.2 16.3 2) (Wet ted surface a rea/Tota I sub segment a rea) x 100 3~ SC indicates side-channel complex W.S.A. 6 10-25-83 13,600 (10 sq ft) Percent of Sub segment Area 52.4 40.3 6.28 15.5 4.59 5.8 26.6 9.2 3. 11 13.7 0.33 4.0 110.9 9.3 66.3 45.2 0.62 3.3 0.53 7.4 5. 811 10.5 2.80 8.8 0. 13 4.4 12.2 111.4 0. 111 5.11 22.3 10.9 s9/t3 ' " TABLE 3 ESTIMATED(l) LENGTH OF TRIBUTARY MOUTH HABITATS LOWER SUSITNA RIVER Date Flow (cfs) @ Sunshine Birch Creek Sunshine Creek Montana Creek Goose Creek Sheep Creek Little Willow Creek Willow Creek 8-27-83 9-6-83 56,500 37,500 3 ,000 1,000 2 ,300 1,000 1 '700 1,300 700 1,500 700 600 2 ,000 2,000 9-16-83 10-25-83 22 ,000 13 ,600 400 600 6 ,000(2 ) 1,300 !)()(; 1 200(3 ) ' 14 700(2) I 6,300(2 ) 6,300(2 ) 2,400(3 ) 2,400(3 ) (1) Estimate based on observations from helicopter and from aerial photographs . (2) Sharp increase in length due to tributary flowing into a side-channel which is no longer overtopped at upper end . (3) Increased length of tri butary plume downstream due to lower main stem flow . 0 0 I ~------1~--_11----1~----:-:-f:---_ - -~-------t-·--.-r-__ -_-.:::::-. -+-·--I -, r---1---t-~f---t---t--t----1---t----t-------· -·t ---I . -----t-. --r---=r:.--~_r ___ -----------_,_ I I = 1 --r_j_i_~~ ~~ =--=----~----=-~~----------~---_-___ =_;:--_:_--_+--L_---= _ --=-, ; r-! -1 -~-·-! ---r--. -~--. _.____ ·---. ----,,---· !--,--.=---t--1·----!-I : ··•--j-·-•·! . - 100 ·-I j 1 ---1 -I ~ M"ains:teiil I i --:----- -· c---~---c. Mains:t:em II. ::._1 --~=-j -=· =i :::..:::... ==.-· 90 -~-~ =--:£M'a-in~~"i:i~::::::,t::::::====:.-_--'----+---+-----.,----.-:--------::::::::1 I c ~=--~ Mains't.em IV --·-; ·J:-· I --::--::-::-j-· : ! I· ---L=--. --_:]_-· --!-. so l r -·-1 ---·, -------~:::::;::::---~----~---__ -_++---_-_-_-_~+--------~--------------~~---, --+-· ·--'---. J . --+--' - I --~ __j -·t =--~ ~---1--1 - I.- ~ I ..... 70 . ---- 0 X ..... _. I r . 1---1 ICC ·--~--·· ~ Go ---------~--~ ICC ~---,_ i o-l ICC ~ 50 -_-_-_.....,_ j,___ ......... . ICC ~ ICC 0 ~ __ .. --- -1-----+ --!...- -·----· . ---t ------1--- ---1 ----- ----1 i 30 ____ ._ .. -__ -:-i-----1 ----~--------i'-------1---._--+----:!-- • I I . -~==-~-.... -:.-=1-=-~=t.=== ---r -=--: --------~-------~---------+----~----------~ . ------l -~- ~ 20 ____ , ___ --_;-=.·.::-:-;·- E-< 1 0 .. _ o--- 0 10,00 0 __, ____ ___.__~1 20,000 30,000 40,000 50,0 00 FL0 \·1 (CFS ), S US ITNA RI VER ,\T S UNSHINE PERCENT WETTED AREA VS. FLOW MAINSTEM SEGMENTS FIGURE 1 60,000 F. I. GRID. PROJ.NO r,wG NO c c .--1 0 t<l ~ ~ ..J ,:f. ____ [_ ___ ----·- --, ----,~-... --------'-----------------------.. --·· ---r-----( ·---·--·-- C--------~~ SC-I -- 90 -__c.::--=-=.--(: SC-II - t:.-:.: ---=--=-~:::. sc-rrr---- C--= . =. --:C SC-J:V - so ----·_:--I ?o ------- I - . -l --1=- • I ----1 -1---- ------;--------.. . --~· • -1 --I . - I ,-----=t-=-=-~-. --~ ' --- -i 50 ------------------- ----------4------ ---1 !---_-. ~ l:~ ~--:-~ :-:=t ---==:;-~--.-·-. -= . I 30 ----------·------- ~ 20 ------------- 8 10 . - o--- o 10,000 20 ,000 30 ,000 40 ,000 50,000 FLOW (CFS), ~US ITN A ~I VE R AT SUNSHINE CENT WETTED AREA VS . FLOW CHANNEL COMPLEXES FIGURE-2 60 ,000 c-e GRID. r--------· ·----1 PROJ.NO f------------ OWG NCI ---'---------------- ----r-------_____ -___ -_ -_-_-_______ · _--~----- ----r I ----I ---!-------------,-- 100 0 0 rl OWN. C><O DATE . SCALE. '--- --r--_..;.-=----.o sc I -1-- -· (':---- --::-sc J: -=2_-= -I l 90 --~-~sc r-3 -----r-----------~----------o-:--=~-;. --:::J sc r..,4:":" I ----, ! '---·-- 80 c:= --=--=-=---c sc<......::r=:....--=s_·-------'----------'--=--:·::::::::::::_· ____________ _ _A-----~ SC I-6 ---==r=-· 70 -----------. ] --· __ .___,_ __ -:~--- ·--,-------·---------·-------- 60 --''--------! ---+--------·---. ·r-· 50 40 -------------- --. --~ -___ ..;.:;:&--·--:::::-~;~ -~--... o-----~ ./~ -~----.._ ~--=--.-....::; ---- 30 ,., -·-•::;::..€ . -------· ---,..,:A 20 -------~-~· ~-- -- -~ -----·---.. .....-G - ~-----~. ~~ ---<:l_ Q'3 --~ -::::--::-=--........--("3€!-~~~-==-.:.----= 10 -- o------ o 10,000 ··-·-· .... -· ry--0---- 20,000 30,000 40,000 5 0,000 FLOt·l (CFS ), SUS ITNA RIVER AT SUNSHINE PERCENT WETTED AREA VS. FLOW SC I-1 '1'0 SC I-6 FIGURE 3 6 0 ,000 F. B. GR ID PROJ .... O OWG flO ----: ---1 _:.:c_ -r--i _..__ --~--------.. -------+-- 1 0 0 ---o-----<c sc II--1 0 0 r-i C>------.:: SC II-2 l 90 -~---_--...,Z\..--sc-II. -3 ___ ----,.------------------------·-----' ..-------------I a--:-7..=__ = SC II-4 -r= _, ___ _ 80 ·-_--i---____ , -I 7o ----. -· ,_ ---. -· .. '.-:··-i -1-----~.-------_· __ _;_'-=--==---· __ ___._"T""l------_---------::-=i 60 ------·---- 1---· ! -=!=--· ·---'---·--·-1 ·-. ----- --... -~----1 - -; !--r---· 40 30 ·--------- .:l g 20---- E• OWN. CKO DATE. SCALE. 1 0 - o--- o _______ ___.. 1 0 ,000 20 ,000 3 0,000 4 0 ,000 50,000 FLOW (CFS), SUSITNA RIVER AT SUNSHINE R&M CONSULTANTS, INC. ~N01 Nt.la •• 0 E 0 '-0 0 1li 1'a Ot..ANN•aa b UAV I:YC Ra ".':--======::-:-=: .. -.-__ -.. :.-. ------ PERCENT WETTED AREA VS. FLOI<l SC II-1 TO SC II-4 FIGURE 4 . -·---. 60 ,000 F. B. GRID PRO.!. NO OWG.~O '---------· j _______ : --·---- -----------·--------·---, ••--• I :: ~--=~ ---= . .:. -----~ ~ ·-T ---_- ---. r ----~i-----~~-------~------4~-----:-_-_-_-__ ~~ --------------1-L--------, ·--------- ---------· ---·-1 _,_, ___ ,..._ - 10(' -. ~-sc -r t=? 0 0 ..... X ICI: 9 0- 80 [l! 60 .:: ----------------------- -V _____ -c SC II-6-_-_-_--:_-_ _----_-.::_ -=-----_--i,__---- ~~-J~-~~---------~~--~----_-_-_-----·------~,------------------1 ~ __ ·_·::;-~ SC I -i-=8---i •---------..!..._-_-_-·-:_ _--:_-_-__ -- _, l ---=L=-~ ---!------'---------~=------=-=-~ -----·-1---____ J_ __ -----1--_.__ :::.-::...=. -~~--·---=-~ :i'l-,--:_---_:._-!==: --l~--·---_-.:._·· _!_-------------·-I t---•· -------+---------------+i ·--.-. -:--::-1 --_-_ _1 i -----·------ ~ -·-...:.:::=·--t :--==. :..:=--===--1--=-~-~=·-__ _:-__ ----1 ~ 50 ~ ---·: __ ~ 40 --------------- 0 I r.l _, __ i: ~ 30 ~ ~ 20 8 10 - --__ , -·--~ -· -----·-----. -----·---------~-~ --· ---·-/ ---~---·--. -~-~~::..:-~-. ----------------,..~ ~----~ .. ~~---- / ~., ~...;::...;=.::-.:-.-.---:":n-.:----::;7· -'--1---------. ~ I • --~--- ,• •/'/ . I ~/ /. : -1.:1 -;;L-----------:::::::::' =-·~--4;..._ ______ _;__ __ _ ~ _ ___,__...... -- --_, __; -I I .. ··-----~ I 0 0 1 0,000 2 0 ,000 30,00() 40,0 00 50 ,0 00 6 0,000 FLOW (CFS ), SUS ITNA RIVE R AT S UNSHINE OWN. PERCENT \ot"ETTED AREA F. B. CI<O vs . FLOW GRID DA TE. sc !1-5 TO SC !1-8 P ROJ.NO SCA lE. F IGURE 5 OWG NC ----. -·---.. 100 90 ' ------·-----.--·----r- ---·---------r----1--------·--·----+-------+--_:.. _____ _._ __ -+r=. ---· ------ -------· ----·----·---..-·----- --+------ -a c sc 10(=..9 -----------··----·--· SC -I:E-:H> ----'--- -==........_ sc _ .... r....,3.:::-..Ll..L!o-._-_-_-_-_-_-_!f-_:::::-._-_- -~-j ---t----·--4---so------------- ---I ----1 0 0 .-i 70 X -~ ~ ~==~-=-==-~~~=-] __ -=-=~::_ :__~-~~-:_ ~-=-: ·---·-~---.. I . --~---. . .. --·I ...... --------. ··--I I ----:--•. ----j--~ . -;--·-------~ 60 ..:_-_-_-_-::::_-_-_-_:_::-_-__ -_·· ___ ...,: ____ .::::_-_-_-_-_ .. -_ -_-_ -----==-+-·:::::_-_-_-_-_-_--+-, _·_-_-~ __ ----:-:_· --------~1 II( --------·t--.L -!------' . ---, __ : -. 1-__ ..._ .. - ---. --,_ ·--1 ~ so .:-~~~-~=--=-::-t ·-==-==-.: .. =-~-=--=!::==-----· ·--t-. _--_--_:_·. ~ -----· . _·-__ --__ ··---E:_·-==-r..::::::::~.-;:-----,.. __ ,:..-·.::.:.:: ~-=--~ -=--=-~ ~ 40 --_-_~_-_-___ ......;.__ . --=--=--+=---===---I -:-=--=--= =-.I 0 . ·-----·---. -·-·· ·.-::-:·:· ---~---·· ~ ------· ---_, ___ ··-·· ~ -------. -:-.·. --=---~ --· IJl 30 ---·-·--r,)-----. ---~.:--·---=-=_,....,._ -__ --__ :...+=;:-=-_------- 3: /""'-- - ----~. • I g 20 _____ : ----~-, ·--:-~ -~---=<----·--l===~===t--·-_ =----. -- 8 / ---··---r:-.=----. ·--.-1 ~ --= (j' ~--. . r.'\ lo --. ·------! -·---~~-=---~~~ r::r---. -· ~ :--o-------~0~----~&.-~~~======~~----~-------------~ 0 10,000 20,000 30,000 40,000 5 0 ,0 00 FLOW {CFS ), SUSITNA RIVER AT SUNS HINE PERCENT WETTED AREA VS. FLOW SC II-9 TO SC TI-ll FIGURE 6 60,000 £8. GRID PROJ.NO DWG NO \._ 'l I I J . ' ___ ,, _______ ._ ______ .__ _____ _ ---------' --~ --:----------!~----=--===--; ·--'---l-___ ::-:::-_-_---.=--:::1 -·----, ---. --. -------, ,__ ·-------------r--------I -_-_-_·------r! ----·--------·-~ ----r----r-----·- I -------·--------- ·----------L----- -_-_-_ -_t=_ _-.::-.::-..=.+.-=--===--_-_::::_-:_-~-=--=--_~..~.... -_ -_:__-----~_-_-_-:-jtc:::_---=---__ -_-__ ---_·_;~~--.-_ -=-~~ -------·----------·--- ----------.-----. ---· ' -·-·-------I ;-------+---- 100 .=b ---1.) -sc:-r!£:=1 ·-___ ---· ----· -----·--· -:-c--~~--~-sc-ill-2 ------. ---_-__ -·---_-_--::::: _:·:-__ .. _~! 90 . -~ -. -::s SC. I~I-3 i . _; I I f".=--==-.:_~ scr:rr-=-s__ __ -------t------, . ---·-==--__ ~~-= -------------L--___ :~-----------____ , 80-- ~··.:_ 0 SC I tl=-4 ·--·--:'~---·=----~----:_:::_-_ -------· -· --~-·-· 0 ---------·----1---_____ ..__ --. - ~ 70 --------·-· ----·--. ------1--.. -!-.. -----,! ·------''------~------~---·----- X I , J -_i ___ , __ ·----l-· ·--· ,-------------·---I j _I -' _=.,===-: r--I -=-=-~--~ ---~--. ---~--- ----·---·------ , f---I ------g -+--__ I • -·---1 --....! --· l -. ··-----:-. I • -~ _ ______ _J -----'----: -1-----. - .------1---~-.. --.I -·-·-' . ------.. ~--·-· -· . . ----·-·-----{ _____ _ -~ ·--:=-==!='~==: 50 A; i --·-----1--- ! 40 =~~~----_-_-__ ·_-._-----. -------€=§-··---r------* ·----1 --. --· --====-----r----------~-~ ---·--------.! . ·-=.___l_ --. --·-----=l=·=== I := = :-:-] . -·------. ·------L------. - 0 --· -----· ·---· ' i E 30 -· ----___ --:j -:==-~: ~--~:-:---~:i--,;;&1 ~_._·=; 3 '--c=:--1-• < e ..:r ------·-' . ~-.:-=: j, / 0~ 2o --------=--=---·_--_ --~~-------./-f .. __ . __ ~~ --, !' .-...tr') e-. ~--·--~i ~--,4-----::;;:::-=-~_-:--··· ~--------~ -,..-_.-1-_. ----·'3---= ea ~ --.. ,r --. . .. , . . -:__ ~ ' . (:'(' G---'=" ·-- - - - - - - --"\:: e-----~ . ·--- 1o ---· 0------------ 0 10,000 20,000 30,000 40,000 50 ,000 60,000 OWN. CKO DATE. SCALE. FLOW (CFS), SUS ITNA RIVER AT SUNSHINE PERCENT WETTED ~REA VS. FLOW SC III-1 TO SC Ill -5 FIGURE 7 --.. ·-- F. B. GRID PROJ.NO OWG.NO ·-------.. , -. 0 -------;-------r ---- -------±= 100 I IV -1 o· -o -sc ----1-----·-·· _,_ ·--r---- ---,--·--::-.:.:_-_---=~ _-_ ·--····--=r= ------- ----1 . -·---I --·! ---· -i ------, ·--·---·---! -------------· -----·-- -=:-.o-_...:, __ .. ,.... sc IV~-.._, 90 ---~-s:sc q-3 --· ---~---_·-_·-_-_-_-_-_-=----~-----_--_-_= ____ :~ --~~-__ -_-_· 1 11 -::-·-~ --,;-l·. _:...:-; SC IJ-4-: -----~1.----·---. 80 ---------------------~-----··-·-+-·-------· --- -------------i . -------! -----"----·------------~--------. ----1 ___ __l -..... ---- 0 -----------~--__;_----!-------------1 ,..... ?o--------------''--------!.---------·---------·- X --------··---- 60 ---~.----~---- ..:I ~ ....... --·---r----------,---.. 50 ~ ~ 40 ------------ 0 (IJ ·-r------. , ___ t ... __ !._ ___ _ ---···--------·-· ---. --...... --i ----------;:-.:-.-:::-.-:. -·~i=-_.. :::::0-·: ti 30 --· ·-----~----·-- -~-1 --- --. El l---· -- ..:I . ----~·-•.• :-r ··~~ ~ 20 -----------· -.. -c==:'.....-::~.:.:;;...:;::.-..+-----~--:-::-~---;- .. -p------,:_ -...,_.-A=--! ~ ~~--I ·-j--·- 1o ---··---• ~-:I"' , • ----- . • -----·----..., OW N. CKO. t--· DAT E. S CALE. I -· ~- o----------------------------------------------------------------- o 10,000 -· --___. 20 ,000 30 ,000 40,000 50 ,000 FL0\·1 (CFS), SUSITNA RIVER AT SUNSHINE RCENT WETTED AREA VS. FLOW IV-1 to S C I V -4 FIGURE 8 . ·--·-- 60,000 F. B. GRI D PRO J.NO 1--------- DWG.NO .. ----'----~···----------I ----·-·-_____ .._ ____ _ ---{---·::- ---t--~_L_-_i -----.L -----~=---==~ ------------~ --"---·----_;_ ____ ----------· ----:------------.-----t-----------!--------··-_____ _........_ _____ ---- 100----~~---------------_. ______________________ ~----------~--------------------~ -==o--n~-===:..::..::<o sc r_.V-!_s-_ ---._-_-_-__ -_ -__ -------------------_-; 90 ---~---~----~* ~~::-..--=-i-.;-=_:~--__ --+--~--~=---F ·-:·=~;:~~~j -' ----~---· 0 0 r-1 .... so ---------- ' ____ ____; ... ·r-· - ~ 60 oC ---_+j_~---· ----''--------- I 50------~------·-----·---- a ·-------·----''-----+--------· ' i -··--i·---+-1------·---- -~--------rl--~---1 • ---1!----'' L---+--·--t----.-1.---_ -=--=1 ·-:=:_-:_-:-::-, ____ =-.--~=-L ~ -·-· ::::t~:..:..:..-_-_-_---t. -::.-== :-:-. -===:; -· ----! -----! . --. ·----t-----,1·--·-1---------+---~ l ,--1-----~--· . ·- ---....!---~-+-----.... =+=--:----'-----+--------- oC 4o----~------------- 0 -----· -··==--= ·::..::.. -~ --:-=:;~-:-=f::.=-....:::-E ·---_ =---·-__ ~___ ·-·---·---·-=[:::=-~- :.; ~ 30 --·------------. -__ -__ -__ --__ --=::-.....,_,...._j::.·-=.....:~=--r-. ---- ~ 2o--------------_-_-__ --_-_·~~~~---~-.~----~~~---------;-__ ._._:_~--~-~-----r~------:_:_-_:_:::_~ __ -________ -~j ~ .... ~ ---. ~-t =-~-=E :-··---··· ·-1 o-... 1o ---I I I - .. . I -I o---------------------------------------------o 10,000 r-·------------, OWN. CKO DATE . SCAI.E. ------_. 20,000 30,000 40,000 50,000 FLOW (CFS), SUSITNA RIVER AT SUNSHINE PERCENT WETTED AREA vs. Ft.Ot-1 SC I V-5 TO S C IV-7 FIGURE CJ 60,000 F. B. GRID. PROJ.NO. 1------------ DWG .NO ALASKA POWER AUT1-10RITY SUSITNA hYDROELECTRIC PROJECT LOWER SUSITHA RIVER 04Tl ~ """tOCJt.tP't1"l S(PT 1., 198.) SC . .&U 1••l000 WET l Of 11 CAll z~J-14 H.ULHlAICQ ---.... ~ ' ... _,- ·. ALASKA POWER AlJTHORfTY SUSITNA HYDROELECTRIC PRO.IECT \ ·. LOWER SUSITNA RIVER S{P.T I rMl SHu · c c..-n CATl Z•J'•I4 \ ·. LOWER SUSITNA RIVER S{P.T I rMl SHu · c c..-n CATl Z•J'•I4 -• ,'(_ ~" I ··~J . I.OWDM*TNA- DlT£ Of Pt+OTOGIII.Vt4Y SE:P T 1•.1MJ ti:AL.t ···lOCO' SH[['T . s 01. DllTl: , .. ,_ .. .. ALASKA POWER AlJTHO~ S\ISITN-' HVDROElfCTI!IC PROJECT LOWER SUSITNA RIVER :.t"'£ ~ ;;to.;OtO~IIf.lP"'f ~PT 6,rHl se:....r '•lO\.o s;,ut & or .tl ll&'"t Z-7-l.t ... . . I • I ALASKA POWER AlJTHORIT'' SUSITNA HYDAOEUC"Tl!IC PROJEC"r LOWER ~A RIVER Do&'"I :::1 .... -ra'~, st;t• •.Ml -.c.:_r -. noo w.rt • C!'" z• Ot.f£ Z ·1·14 lOWER SUSITNA RIVER I :.:.•t 01 ~TC'G~··ft' $l71' I , .A) ~£ l'OOG s..t.[• ' Q,. l. t.tn: ,., .... • SUSITNA HYDROEUCTRIC PROJEC r LOWER SUSITNA RIVER 0 .A1'[ 01 P .. OTOC.AAP,.,t SEPr 6.t98l 5Gl E lOOO 5ttEff 10 Of U C.:.t( 2-f ·l • LOWER SUSlTNA RIYEII ~-y !!I llNIQ~.a..Foolt st•• ~~l . c.~ ll ~ l'OCiO cut l-7-14 ALASKA POWER AUTHORITY SUSITNA H YDROELEC TRIC PROJECT LOWER SUSITNA RIVER C,:.f[ Q1' PI'O'()l(it.G:.Pot't S[Pr ll,t!e) SOU: ··lt\l) WfT IZ C" U D&Jl l-7-IC • ALASKA POWER ALJTHORITY SUSITNA HYDROELECTRIC PR OJECT LOWER SUSITNA RIVER O:.f[ Of F'WOTOGIUPft't S(PT l l,r'JIIl s..:...t ,. ?OCO SM££' ., o~· zt Q.1H 2-7-a4 ALASKA POWER AUlliOAITY SUSITNA HYDr.OEL£CTRIC f AO.£CT LOWER SL'SITNA RIVE l o.t •t Cl ~~"' SEn 6 .M! 50U '. •lOCO sPIRT 14 (!r ,. k=--=--=c--r--.. ;_rt.:._ -'7-&4 -J:'~L- ALASKA POWER AlJTHORITY SUSITNA HYDROEI.£CTRIC PROJECT lOWER SUSITNA RIVER CA1'£ 01 •woToc;•'-Ph'l S(Df !6 .tMl ~E ··lOOO· KU " OF 21 OAT( Z-f-1• l!A2ZHJ.UCO ; SUSITNA HYOROELECTRIC PROJECT LOWER SUSITNA RIVER l)ol'l( 01' ~TQG.a&Potf Sl~l >1 .~ 5ot.t.L.l ~.lOCO SMUT t4 0 1' .t1 CAfl l -7·8• H.A:UA·m:co ALASKA POWER AlJTHOAITY susmu. HYDROEUCTIIIC PROJECT lOWDI SUSlTNA AIY£A !).I.T£ Gl" ~CCR.l.PwY u_rr 1•.1J1l SC:~[ lOCO $k(£T IT Of ll DArt 2 -t~ 14 ALASKA POWER AUTHOAfTY SUSITMA HYDROELECTRIC ~CT LOWER SUSITNA RIVER ~f[ 'Y il'lo!OT~IIt'-hr 'S(.•t .. ,M.J SCJ.-!. 4 •l:<:G HU 11 Of 11 Q&T[ l-7·t!• L OWER SUSITNA RIVER ~U l)f h0'"'C~It~Y S£PT 6 ,(98) ~.&.&..( '•l:KIC $~-!((• ZOCf 21 CJ,.T( l-7-1!14 IJAJU · n .t:C) ALASKA POWER AUTHORITY SUSITNA HYDROElECTRIC PROJECT l O WER SUSITNA RIV£R ~1( 01 e»,.,()lCGIIt"-""f Y..,l' ~. W) sc....t ···zoc.c ~n 11 M u t.A·t 1-1-ac ___?~ WZHJAICD ..... ·-·-I .... , ....... ,.-·'\t"'f L OWER SUSITNA RIVER 0.11'£ Of' P,;QTQGRAPI'IV S(;l't ~i:~l l2 OF 21! SCALE l••zOOO CAT( 2-7·1 • ALASKA POWER AUTHORITY SUSITNA HYDROELECTRIC PROJECT LOWER SUSITNA RIVER CoAl( 01 '""'>lTQ(j.Q-4P,.'I SEPT t6.r91) SCJ.L £ 2000 WE T Z s C~' 21 Q.2.1 ( Z -7-!1 4 ALASKA POWER AUTHORITY SUSITNA HVO!;OELECTRIC PROJECT LOWER SUSITNA RIVER Oo\Tl Of ~O T QG CUptty S(PT 16 .tM3 .5C.ll£ ,., 2000 ~ET Z4 OF' Zll CA1'£ 2-7· a• ALASKA POWER AUTHORf,-y SUSITNA HYDROELECTRIC PROJE•:T LOWER SUSITNA RIVER OATE Of ~OTCGit.O:P"Y S(PT 6,198l SC.U.t l••zOOO SMUT 26 Of Zl OAT[ Z -7-J I. ALASKA POWER AUTHORITY SUSrTNA HYDROELECTRIC PROJECT LOWER SUSITNA RIVER O.Aft Ql' Pot0TOG~.t.Pn1 S(PT 16,198) SCAL ( ·, 2'000 ~£1' t1 Of 21 ()Qf[ l-7-14 !I.AliLH)J~CD ALASKA POWER AUTHORITY SUSrTNA HYDROE.LECTRIC PROJECT LOWER SUSITNA RIVER CAT( 0T .... ;)lG;_Iti..PtoiY !t~T ,.M"3 KAi..[ 1• • l.:.CO" ir££• 1.1 C# II QAT[ Z -1-14