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HomeMy WebLinkAboutAPA2746/ FINAL REPORT JUNE 1985 DOCUMENT No.2746 OCT 29 1985 ALASKA DEPT.OF FISH &GAME CONSULTANTS,INC. suPvEYCRS REGION II HABITAT DIVISION SUSITNA HYDROELECTRIC PROJECT EFFECTS ON NAVIGATION ALASKA POWER AUTHORITY_,_---' O~L%=~~L%@©@ NA J01NT VENTl,RE FEDERAL ENERGY REGULATORY COMMISSION PROJECT No.7114 SUSITNA HYDROELECTRIC PROJECT SUSITNA HYDROELECTRIC PROJECT EFFECTS ON NAVIGATION Prepared by R&M Consultants,Inc. Stephen R.Bredthauer Bob Butera Under Contract to Harza-Ebasco Susitna Joint Venture Prepared for Alaska Power Authority Document No.2746 Susitna File No.4.2.2.1 Tk \y?-5 ~St3 F~t-~ 1\0.a=t~~ Final Report June 1985 tJRO,JECTHynii(~J::LI=(_:Tr:IC VIGATIONur"t~Ai=F~E{;TS ..- N..- ~ ooo 1.0 1.0 I""'- M M - ARLIS AlaSka Resources Library &Infonnation Servlces Anchorage,Alaska EFFECTS ON NAVIGATION SUSITNA HYDROELECTRIC PROJECT TABLE OF CONTENTS Section/Title List of Tables List of Figures 1.0 SUMMARY 2.0 INTRODUCTION 3.0 DESCRIPTION OF RIVER 3.1 Susitna River Morphology 3.1~1 Morphological Characteristics of Devi 1 Canyon 3.1.2 Morphological Characteristics of Devil Canyon 3.2 Flow Regim 4.0 DESCRIPTION OF WATERCRAFT 5.0 ACCESS 5.1 Willow Creek 5.2 Susitna Landing 5.3 Sunshine 5.4 Talkeetna 5.5 Alaska Railroad/Aircraft 5.6 Denali Highway/Lake Louise 6.0 DESTINATIONS 6.1 Cook Inlet to Talkeetna 6.2 Talkeetna to Devil Canyon 6.3 Upstream of Devil Canyon 7.0 USE OF RIVER 7.1 Historical 7.2 Summer Uses i Page iii v 1 3 4 5 Upstream 5 Downstream 6 11 12 14 14 14 15 15 15 16 17 17 18 18 19 19 20 - - - - - - R22/8 3 TABLE OF CONTENTS (Continued) Section/Title 7.3 Winter Uses 8.0 NAVIGATION RESTRICTIONS 8.1 Cook I nlet to Talkeetna 8.1.1 Cook Inlet (RM 0)to Yentna River Confluence (RM 28) 8.1.2 Yentna River Confluence (RM 28)to Susitna Landing (RM 61) 8.1.3 Susitna Landing (RM 61)to Talkeetna (RM 97) 8.2 Talkeetna (RM 97)to Devil Canyon (RM 150) 8.3 Devil Canyon (RM 150)to Devil Creek (RM 162) 8.4 Upstream of Devil Creek 9.0 WITH-PROJECT CHANGES IN FLOW REGIME 10.0 WITH-PROJECT CHANGES IN RIVER MORPHOLOGY 10.1 Watana Reservoir 10.2 Devil Canyon Reservoir 10.3 Devil Canyon to the Chulitna River Confluence 10.4 Chulitna River Confluence to Cook Inlet 11.0 WITH-PROJECT CHANGES IN THERMAL AND ICE REGIME 12.0 IMPACTS ON OPEN-WATER NAVIGATION 12.1 Watana Reservoir 12.2 Devil Canyon Reservoir 12.3 Devil Canyon to Chulitna River Confluence 12.4 Chulitna River Confluence to Yentna River Confluence 12.5 Yentna River Confluence to Cook Inlet 13.0 IMPACTS ON OPEN WATER NAVIGATION 14.0 BIBLIOGRAPHY ii Page 23 24 24 25 25 28 29 30 30 31 32 32 32 33 34 35 38 38 38 39 39 40 42 43 ..... R22/8 4 TABLE OF CONTENTS (Continued) Section/Title TABLES FIGURES 46 77 - ,...., - - - -. Cover photo:Going up Susitna River on Riverboat Betty M.August 1919. Location of photo was near to Gold Creek.Photo courtesy of Alaska Railroad,Collection. iii .- - -. ...... R22/8 5 Table Number 3.1 3.2 3.3 4.1 4.2 6.1 6.2 6.3 6.4 7.1 7.2 LIST OF TABLES Title Susitna River reach definitions. Periods of record for gaging stations. Filled streamflow summary,Susitna River stations. Boat draft by exit location,1984. Boat class by exit location,1984. First destinations for boaters exiting at Willow Creek,1984. First destinations for boaters exiting at Susitna Landing,1984. Fi rst destinations for boats by exit location for boats engaged in sport fishing,1984. Fi rst destinations for boaters exiting at the Talkeetna boat launch or airstrip,1984. Percent of boats by activity and month for boats exiting at Willow Creek,1984 . Number of boats by activity and month for boats exiting at Willow Creek,1984. iv 47 48 49 51 52 53 54 55 57 58 59 .-. .- .- - R22/8 6 7.3 7.4 7.5 7.6 7.7 7.8 8.1 9.1 9.2 Percent of boats by activity and month,Susitna Landing,1984. Number of boats by activity and month,Susitna Landing,1984. Percent of boats by activity and month for boats exiting at the Talkeetna boat launch or airstrip,1984. Number of boats by activity and month for boats exiting at the Talkeetna boat launch or airstrip,1984. Number of people for residence groups by exit location,1984. Number of anticipated visits by exit locations, 1984. Boats with navigational problems by exit location,1984. Flow constraints for environmental flow requirement Case Eyr. Flow duration data at Gold Creek for natural, Watana only (1996 load),and Watana/Devil Canyon (2020 load),open-water season. v 60 61 62 63 64 65 66 67 68 - - - - - - - - R22/8 7 9.3 9.4 Flow duration at Sunshine for natural ~Watana , only (1996 load),and Watana/Devil Canyon (2020 load)~open-water season. Flow duration data at Susitna Station for natural,Watana only (1996 load),and Watanal Devil Canyon (2020 load),open-water season. vi 71 74 ,.,.. ..... - - ..... R22/8 8 JFigure Number 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 3.10 3.11 3.12 LIST OF FIGURES Title Single-channel river pattern. Split-channel river pattern. Braided channel river pattern. Multi-channel river pattern. Split-channel morphology below West Fork Susitna confluence. Vee Canyon. Susitna River near Watana Damsite. Rapids at Devil Canyon. Single channel morphology,Susitna River,RM 150 to RM 144. Split-channel morphology,Susitna River,RM 144 to RM 137. Split-channel morphology,Susitna River,RM 137 to RM 131. Side channels and sloughs along Susitna River, RM 126 to RM 11 9. vii 78 79 80 81 82 82 83 83 84 84 85 85 - -- - - - - - R22/8 9 3.13 3.14 3.15 3.16 3.17 3.18 3.19 3.20 4.1 4.2 5.1 5.2 5.3 5.4 Sing Ie channel morphology,Susitna River,RM 110 to RM 104. Confluence of Susitna,Chulitna,and Talkeetna Rivers,RM 102 to RM 95. Braided river morphology downstream of Talkeetna, RM 72 to RM 65. Delta Islands,RM 50 to RM 43. Deshka River confluence. Yentna River confluence. Monthly and annual flow duration curves, Susitna River near Denali Cantwell (Vee Canyon), and Gold Creek. Monthly and annual flow duration curves,Susitna River at Sunshine and at Susitna Station. Jetboat. Airboat. Location map of boating access points and major destinations. Willow Creek boat landing. Susitna Landing. Sunshine boat landing. viii Page 86 87 88 89 90 91 92 93 94 95 96 97 97 98 8.8 Confluence of Susitna,Talkeetna &Chulitna Rivers.109 - -. - - - R22/8 11 5.5 6.1 7.1 7.2 8.1 8.2 8.3 8.4 8.5 8.6 8.7 8.9 8.10 10.1 Talkeetna boat landing. Timing of salmon runs,Susitna River. Alaska Engineering Commission twin screw riverboat on middle Susitna River,1919. US river steamboat,Omineca at Kroto Landing, 1917. Head of Alexander Slough. Powerline Slough. Side channel at Susitna Landing. Upper end of Delta Islands. Head of K roto Slough. Confluence with Sheep Creek. Confluence with Birch Creek Slough. Boulder-strewn reach at RM 112 to RM 113. Main channel crossing floodplain at RM 128. Channel cross-section,RM 128.2. ix 98 99 101 101 102 103 104 105 106 107 108 110 111 112 ..... - ..... .- , - R21/10 12 1.0 SUMMARY The Susitna River is presently navigable by shallow draft water craft from its mouth at Cook I nlet to the mouth of Devil Canyon,150 miles upstream. A '12-mile reach through Devil Canyon contains world-class whitewater rapids,navigable on Iy at moderate flows by expert whitewater kaya kers. Upstream of Devil Creek,the 150 miles of river are navigable by most typ1es of watercraft,but use is generally limited to hunters boating the segment above Vee Canyon. Access to the river below Talkeetna is from boat ramps at Willow Creek, Susitna Landing,Sunshine,and Talkeetna,with Susitna Landing the site used the most in 1984.Access to the river above Devil Canyon is limited to the Denali Highway,and th rough the La ke Louise system and down the Tyone River. ThE!lower Susitna River is primarily used by sport fishermen,with destinations closely related to the timing and location of salmon ru ns.The Des.hka River and Yentna River are the most common destinations downstream of Talkeetna.Fishermen and guide services use the river between Talkeetna and Devil Canyon,but use is much less than in the downstream reaches . OpE~ration of the Susitna Hydroelectric Project will alter the flow regime below the projects,decreasing flows in the summer as water is stored to fill the reservoirs,and increasing flows in the winter in order to meet the power demand.Changes in the flow and sediment regime caused by ope~ration of the project are not expected to significantly affect navigation downstream of the projects.The reach from Devil Canyon to the Chu Iitna River confluence is completely navigable at with-project flows.Downstream of the Chulitna River confluence,a navigable main channel will exist thr'ough the open water season,although side channels will not carry as mUlCh water during the summer as under natural conditions.In about 10 per'cent of the years,the project will likely have some effect on navigation -1- - - R21/10 13 through Alexander Slough during the first half of June.Alternative routes to Alexander_Creek exist through Powerline Slough or via Cook I nIE!t. Construction of the dams will transform about 87 miles of river from free-flowing reaches into lakes.The whitewater rapids th rough Devil Canyon will be covered by Devil Canyon Reservoir. Winter transportation will not be significantly affected.Ice cover downstream of the Yentna River confluence.is projected to form at about the same period as under present conditions.The ice cover is expected to pro'gress to Tal keetna 2-5 weeks later when Watana only is operational,and 4-6 weeks later when both Watana and Devil Canyon are operational.The ice cover will progress only to between RM 124 and RM 142 when Watana is operational,and to between RM 123 and RM 137 when both Watana and Devi I Canyon are operational.However,the reach above Tal keetna now sees only limited use as a winter transportation route,due to the numerous open leads and to the Alaska Railroad running adjacent to the river.The reservoir ice covers will make winter transportation more feasible in that reach of the river. -2- ..... - - - - - R21/1O 14 2.0 INTRODUCTION The~construction of dams at Watana and Devil Canyon will modify both the natural flow regime and the natural sediment transport regime,thus poten- tially affecting navigation downstream of the dams.The reservoi rs formed by the dams will change a free-flowing reach of river into a flat water reach.This report discusses both past and present uses of the river, including access,destinations,and types of watercraft.Pre-project restrictions to navigation are documented.Followi ng this,with-project changes in flow regime and river morphology and their possible effects on navigation are explored. This report compiles all available information on navigation on the Susitna River.Much of the information was collected incident to other studies and is as such unpublished.Other data are included in various reports or memos,while some is based on personal recollection of project workers. -3- - R21/1O 15 3.0 DESCRIPTION OF RIVER Thel entire drainage area of the Susitna River is about 19,400 square milels,of which the drainage area above Gold Creek comprises approximate- ly 16,160 square miles.Three glaciers in the Alaska Range feed forks of the Susitna River.These th ree branches flow southward for about 18 miles (30 km)and then JOin to form the Susitna River.The river flows an additional 55 miles (90 km)southward through a broad valley,where much of the coarse sediment from the glaciers settles out.The river then flows westward about 96 miles (154 km)th rough a narrow valley,with con- striictions at the Devil Creek and Devil Canyon areas creating violent rapids.Numerous small,steep gradient,clear-water tributaries flow into the Susitna in this reach of the river.Several of these tributaries cas- cade over waterfalls as they enter the gorge.As the Susitna curves south past Gold Creek,13 miles (21 km)downstream from the mouth of Devil Canyon,its gradient gradually decreases.The river is joined about 40 miles (64 km)beyond Gold Creek in the vicinity of Talkeetna by two major tributaries,the Ch ulitna and Talkeetna Rivers.Downstream from thi~;confluence,the Susitna flows south through braided channels for 97 mil4:!s (156 km)until it empties into Cook Inlet near Anchorage, approximately 318 miles (512 km)from its source. Thl3 Susitna River is typical of unregulated northern glacial rivers,with high,turbid summer flow and low,clear winter flow.Runoff from snow melt and rainfall in the spring causes a rapid increase in flow in May from the~low discharges experienced th roughout the wi nter.Peak an n ual floods usually occur in June,but significant rainfall flood events may occur at anytime du ri ng the summer. Associated with the higher spring flows is a 100-fold increase in sediment transport which persists th roughout the summer.Between May and September,the large suspended sediment concentrations causes the river to be highly turbid.Glacial silt,released by the glaciers when they begin to melt in late spring or when re-entrained from the river banks by high -4- R21/10 16 flows,is responsible for much of the tu rbidity.The high Iy tu rbid water oHem makes it extremely difficult for boaters to determine channel depths. Rainfall-related floods often generally these floods are snowmelt floods. occur in August and early September,but not as severe as the spring (May-June) ..... - "..,. As the weather begins to cool in the fall,the glacial melt rate decreases, with the flow in the river correspondingly decreasing.Because most of the suspended sediment is contributed by glacial outwash,the river also beSiins to clear.Freezeup normally begins in October and continues through early December,progressing upstream from one natural lodgement point in the river to the next upstream lodgement point.The river bre,akup generally begins in late April or early May near the mouth and progresses upstream,with breakup at the damsites occurring in early to mid-May. 3.1 Susitna River Morphology Th4:!Susitna River originates in the glaciers of the southern slopes of the central Alaskan Range,flowing 318 miles (512 km)from Susitna Glacier to the river's mouth at Cook Inlet.Throughout its course,the Susitna River is characterized by several reach types.These are defined and illustrated in Figures 3.1 through 3.4. 3.1.1 Morphological Characteristics Upstream of Devil Canyon The headwaters of the Susitna River and the major upper basin tributaries are characterized by broad,braided,gravel floodplains downstream of the glaciers with several melt streams exiting from beneath the glaciers before they combi ne further downstream.The West Fork Susitna River joins the main river about 18 miles (29 km) below Susitna Glacier.Below the West Fork confl uence,the Susitna River develops a split-channel configuration with numerous islands -5- - .... R21/10 17 (Figure 3.5).The river is generally constrained by low bluffs for about 55 miles (89 km).The Maclaren River,a significant glacial tributary,and the non-glacial Tyone River,which drains Lake Louise and the swampy lowlands of the southeastern upper basin,both enter the Susitna River from the east. Below the confluence with the Tyone River,the Susitna River flows west for about 96 miles (154 km)through steep-walled canyons (Figures 3.6 through 3.8)before reaching the mouth of Devil Canyon.River gradients are high,averaging nearly 14 feet per mile (4 m per km)in the 54 mile (87 km)reach upstream of the Watana damsite where the Watana reservoir will be lo.cated.From Watana to Devil Creek,the river gradient is approximately 10.4 feet per mile (3.2 m per km).In the 12 mile (19 km)reach between Devil Creek and Devil Canyon,the river gradient averages 31 feet per mile (9.5 m per km). This 96 mile-long (154 km)reach is primarily a single channel with intermittent islands.Bed material consists mainly of large gravel and cobbles.The mouth of Devil Canyon at RM 149 forms the lower limit of this reach. 3.1.2 Morphological Characteristics Downstream from Devil Canyon .....Between Devil Canyon and the mouth at Cook Inlet,the river has been subdivided into nine separate reaches.These reaches are identified in Table 3.1,together with the average slopes and predominant chan nel patterns. Through this reach,from RM 149 to RM 144,the Susitna flows pre- dominantly in a single channel confined by valley walls (Figure 3.9). At location where the valley bottom widens,deposition of gravel and cobble has formed mid-channel or side-channel bars.Occasionally,a vegetated island or fragmentary floodplain has formed with elevations -6- ..... - R21/10 18 above normal flood levels,and has become vegetated.The presence of cobbles and boulders in the bed material aids in stabilization of the channel geometry. A broadening of the valley bottom from RM 144 to RM 139 has allowed the river to develop a split channel with intermittent,well-vegetated islands (Figure 3.10).Where the main channel impinges on valley walls or terraces,a cobble armor layer has developed with a top elevation at roughly bankfull flood stage.At RM 144,a periglacial alluvial fan of coarse sediments confines the river to a single channel. The reach from Rm 139 to RM 129.5 is characterized by a well-defined split chan nel configu ration.Vegetated islands sepa rate the mai n channel from side channels (Figure 3.11).Side channels occur frequently in the alluvial floodplain and are inundated only at flows above 15,000 to 20,000 cfs.Where the main channel impinges on valley walls or terraces,a cobble armor layer has developed with a top elevation at roughly bankfull flood stage.The main channel bed has been frequently observed to be well armored.Primary tributaries include Indian River,Gold Creek and Fourth of July Creek.Each has formed an alluvial fan extending into the valley bottom, constricting the Susitna to a single channel.Each constriction has established a hydraulic control point that regulates water surface profiles and associated hydraulic parameters at varying discharges. River patterns from RM 129.5 to RM 119 are similar,to those in the previous reach.Prominent characteristics between Sherman and Curry include the main channel flowing against the west valley wall and the east floodplain having several side channels and sloughs (Figu re 3.12).The al [uvial fan at Cu rry constricts the Susitna to a single channel and terminates the above patterns.Comparison of 1950 and 1980 aerial photographs reveals occasional local changes in banklines and island morphology (AEIDC,1984 draft).The west valley wall is generally nonerodible and has occasional bedrock -7- R21/1O 19 outcrops.The resistant boundary on one side of the main channel has generally forced a uniform channel configuration with a well a rmored perimeter.The west valley wall is relatively straight and uniform except at RM 128 and 125.5.At these locations,bedrock outcrops deflect the main channel to the east side of the floodplain. From RM 119 to RM 104,the river is predominantly a very stable single incised channel with a few islands (Figure 3.13).The channel banks are well armored with cobbles and boulders,as is the bed. Several large boulders occur intermittently along the main channel and a re believed to have been transported down the valley du ri ng glacial ice movement.They provide minor obstructions to flow and navigation,but do not have a significant impact on channel morp hology . At the confluence of the Susitna,Chulitna and Talkeetna Rivers (Figure 3.14),there is a dramatic change in the Susitna from a split channel to a braided channel.Emergence from the confined mountainous basin into the unconfined lowland basin has enabled the river system to develop laterally.Ample bedload transport and a gradient decrease also assist in establishing the braided pattern. The glacial tributaries of the Chulitna River are much closer to the confluence than are the Susitna glacial tributaries.As the Chulitna River emerges from an incised canyon 20 miles (32 km)upstream of the confluence,the river transforms into a braided pattern with moderate vegetation growth on the intermediate gravel bars.At about a midpoint between the canyon and the confluence,the Chulitna exhibits a highly braided pattern with no vegetation on intermediate gravel bars,which is evidence of recent lateral instability.This pattern continues beyond the confluence,giving the impression that the Susitna is tributary to the dominant Chulitna River.The split channel Talkeetna River is a tributary to the dominant braided pat- tern.Terraces generally bound the broad floodplain,but provide -8- R21/10 20 little control over channel morphology. results from the th ree-river system combined flow and sediment regime. General floodplain instability striving to balance out the ".,..Downstream from the three-river confluence,the Susitna continues its braided pattern,with multiple channels interlaced through a sparsely vegetated floodplain.The channel network consists of the main channel,usually one or two subchannels,and a number of minor channels.The main channel meanders irregularly through the wide gravel floodplain and intermittently flows against the vegetated floodplain (Figure 3.15).It has the ability to easily migrate laterally within the active gravel floodplain,as the main channel is simply reworking the gravel that the system previously deposited.When the main channel flows against vegetated bank lines,erosion is retarded due to the vegetation and/or bank materials that are more resistant to erosion.Flow in the main channel usually persists throughout the enti re year. Subchannels are usually positioned near or against the vegetated floodplain and are generally on the opposite side of the floodplain from the main channel.The subchannels normally bifurcate from the main channel when it crosses over to the opposite side of the flood- plain and terminate where the main channel meanders back across the floodplain and intercepts them.The subchannels have smaller geo- metric dimensions than the main channel,and their thalweg is generally about 5 feet (1.5 m)higher.Their flow regime is depen- dent on the main channel stage and flow.Flow mayor may not persist th roughout the year. Mi nor chan nels are relatively shallow,wide chan nels that traverse the gravel floodplains and complete the interlaced braided pattern.These channels are very unstable and generally short-lived. -9- ""'" .... - R211/10 21 The main channel and subchannels are intermittently controlled later- ally where they flow against terraces.Since the active floodplain is very wide,the presence of terraces has little significance except for determining the general orientation of the river system.An exception occu rs where the terraces constrict the river to a si ngle chan nel at the Parks Highway bridge.Minor channels react to both of the larger channel's behavior. Downstream from the Kashwitna River confluence (from RM 61 to RM 42),the Susitna River branches into multiple channels separated by islands with established vegetation.The reach from RM 51 to RM 42 is known as the Delta Islands (Figu re 3.16)because it resembles the distributary channel network common with large river deltas.The multiple channels are forced together by terraces just upstream of Kroto Creek (Deshka River)(Figure 3.17).Through this reach,the very broad floodplain and channel network can be divided into th ree categories: -Western braided channels; -Eastern split channels;and - I ntermediate meandering channels. The western braided channel network is considered to be the main portion of this very complex river system.It appears to constitute the largest flow area and lowest thalweg elevation. Terraces constrict the floodplain near the Kroto Creek confluence and at Susitna Station.Further downstream,the terraces have Iittle or no influence on the river.The Yentna River (Figure 3.18)joins the Susitna at RM 28 and is a major contributor of flow and sediment . Downstream from the Delta Islands,the Susitna River gradient de- creases as it approaches Cook Inlet.The river tends toward a split channel configuration.There are short reaches where a tendency to -10- - R21/10 22 braid emerges.Downstream of RM 20,the river branches out into delta distributary channels. Tides in Cook Inlet rise above 30 feet (9 m)and therefore control the water surface profile and to some degree the sediment regime of the lower river.A river elevation of 30 feet (9 m)exists near RM 20, which corresponds to the location where the Susitna begins to branch out into its delta channels. 3.2 Flow Regime Continuous historical streamflow records of various record lengths exist for gafjing stations on the Susitna River and its tributaries (Table 3.2).The U.S.Geological Su rvey gage at Gold Creek has the longest record,as it was established in August 1949.Complete 32 year monthly stremflow data sets for each gaging site were generated th rough a correlation analysis, whl~reby missing mean monthly flows were estimated (Acres,1983).The ma,dmum,mean,and minimum monthly flows for the sites are shown in Table 3.3.Monthly and annual flow duration curves for natural conditions for the Denali,Vee Canyon,Gold Creek,Sunshine,and Susitna Station gaging sites are illustrated in Figures 3.19 and 3.20.Weekly flow duration tables for May through September are shown in Tables 9.1 through 9.3. -11- R21/10 23 4.0 DESCRIPTION OF WATERCRAFT - - Both the Lower Susitna River with its numerous braided channels and the middle and upper Susitna River with their frequent sections of rapids create a boating situation in wh ich shallow water is often encountered.As the boaters say "the river gets skinny"or "the bottom gets pretty close to the surface".This,combined with the low visibility due to silty water, dictates the use of a shallow d raft craft for most boati ng situations.The use of this type of craft was verified in a 1984 survey by ADF&G (Howe, 1985).During 1984,boats with drafts of 8.0 inches or less comprised 90% (2,232 boats)of those surveyed at Susitna Landing,99%(394 boats)at Talkeetna,and 99%(562 boats)at Willow Creek (Table 4.1).In this su rvey,89%(2,340 boats)of the boats exiting at Susitna Landi ng 99%(394 boats),of the boats exiting at Talkeetna and 35%(199 boats)of the boats exiting at Willow Creek were jetboats (Table 4.2).At Willow Creek the remainder of the boats were comprised of 64%airboats (362 boats)and 1% outboard props (5 boats).The type of boat exiting at Willow Creek is oftEm controlled by flow in Willow Creek.For example,81%(100 boats)of the boats exiting at Willow Creek in September (low flow)were airboats. Jetboats and airboats are both shallow draft water crafts.A description of both follows. A jetboat (Figure 4.1)is a planing craft which is propelled by pumping in water through a submerged screen,then passing the water through a turbine and discharging it out a nozzle at a high velocity to provide thrust and steering for the boat.There is no propeller nor any other mechanisms which project below the bottom of the hull.Depending upon the size of these boats,they can successfully navigate waters as shallow as 6-8 inches when they are "on step"(planing).Planing requires fairly high speeds.Water from 16-18 inches deep is required when accelerating to planing speeds and decelerating back to a stop. -12- - ..... - R21/10 24 An airboat (Figure 4.2)is also a planing craft,but it relies on a large fan to provide propulsion and steering.As is the case with jetboats,no mechanisms project below the hull of the boat.These craft are able to navigate waters as shallow as 4"-6"when they are planing,and can run over gravel bars or up onto land with little problem.Shallow water is not a barrier,although the ease and speed of their travel may be hindered. The!se a re not the only types of boats to use the Susitna River.As recounted in the Historical Use section of this report,paddle wheel, steamboats,and barges have made use of the river.A small percentage of present day boaters use propeller-driven boats.Wh i Ie lacking the capability of jetboats and airboats to travel in very shallow water,this type of craft is generally more fuel-efficient and can carry a heavier load, both desirable characteristics when supplies must be hauled in by boat.A minimum of 18-24 inches of water are required to operate these boats,and their use is limited to known deep water channels and landing areas with fair'ly deep water.Self-propelled boats such as canoes,kayaks and rafts a re also used on the river . -13- -I R211/10 25 5.0 ACCESS TO RIVER Access for boats is limited.The existing access points are described below.Their locations can be found on Figure 5.1. 5.1 Willow Creek Th,e boat landing at Willow Creek (Figure 5.2)is approximately 7 miles upstream of the creek's confluence with a side channel of the Susitna River,and is located adjacent to the Parks Highway.To reach the Susitna river,boats must travel the 7 miles on a narrow,winding stream, with numerous gravel bars and overhanging trees.The site is heavily used,since it is the access point furthest downstream on the Susitna River,and since Willow Creek is a primary salmon spawning stream. Access is a function of flow in Willow Creek,with jetboats and airboats the typical craft.Access from this site is not affected by change in flow of the~Susitna River. Due to the heavy use and the difficult boating in Willow Creek,the State of Alaska is planning the construction of a road to the mouth of Willow Crl:!ek,with a boat ramp on the Susitna River.When this new access is completed,it will likely become the most heavily used access point,due to its accessibility to the large population centers of Anchorage and Wasilla, and to its close proximity to the major sport fish areas of the Deshka River and the Yentna River. ~'5.2 Susitna Landing (Kashwitna River) - The Susitna Landing access point is located on the Kashwitna River, approximately 200 yards upstream of its confluence with the Susitna River at RM 61 (Figure 5.3).It is currently the most heavily used access point on the lower Susitna River,with about 57%of the boaters surveyed during July-September 1984 using this site (Howe,1985).Both backwater effects from the Susitna River and flow in the Kashwitna River control the access -14- - ..... .-. r I R21/10 26 to and from this site.Two ramps are located at Susitna Landing.Access to and from the upstream ramp is possible during very low Susitna flows (when backwater effects are less)but is made difficult due to a gravel bar just downstream of the ramp.The bar is difficult to steer around when the boat is at low throttle{as the draft of the boat is deeper and the curTent is strong.When launching,boaters usually avoid this problem bar by boating upstream on the Kashwitna,then turning and getting the boat "on step"so that boat draft is minimized when passing the bar.The second ramp is downstream of this bar and is not affected by it. 5.3 Sunshine The Sunshine site (Figure 5.4)has a gravel ramp leading to a single channel reach of the lower Susitna at RM 83.8,providing access even at ver·y low flows.Boaters using this site were not surveyed in 1984. However,the site was observed by R&M hydrologist during several aerial oVE!rflights of the lower Susitna during the summer.While the number of boats using the site was not quantified,it appeared that the site was not heavily used,presumably because the most frequent destinations (Yentna River,Desh ka River,Tal keetna River,and Portage Creek/I ndian River) a re,more easily accessible from other landi ngs. 5.4 Talkeetna At Talkeetna,the boat landing is located on the Talkeetna River (Figure 5.51)about 1 mile upstream of its confluence with the Susitna River at RM 97.The site is upstream of any backwater effects from the Susitna,so is not di rectly affected by flow in the Susitna River . Alaska Railroad/Aircraft Although a boat ramp is not located between Tal keetna and Devil Canyon, boaters using self-propelled craft (canoes,kayaks,and rafts)may use either the Alaska Railroad or small aircraft to reach upstream points.The -15- R21i/l0 27 -small craft be loaded the Alaska Railroad at Talkeetna andmayon transported as far upstream as the bridge at Gold Creek at River Mile ~(RM)136.5 (Figu re 5.6)or to the bridge over Indian River,about 1 mile above its confluence with the Susitna River at RM 138.5.Whitewater - - - - - - kayakers sometimes use helicopters and float planes to reach the river up~;tream of Devil Canyon.The Devil Creek to Devil Canyon rapids is one of the most outstanding and challenging kayak runs in the world,so difficult that,as of September 27,1982,only 29 runs (17 successful)had beE!n made through it since the first attempted descent in 1972 (Knik Kanoers and Kayakers,1983).No reported attempts at rafting the rapids have been found. 5.€!Denali Highway/Lake Louise The Susitna -Rive-r from Devil Creek at RM 162 (head of Devil Canyon)to the!headwaters is accessible from the Denali Highway at either Denali or at the!Maclaren River:Boaters may also reach the upper Susitna by boating thr'ough the Lake Louise Lake Susitna Lake Tyone system and continuing down the Tyone River. Historically,the upper Susitna River has never received a large amou nt of usage due to the barrier to upstream and downstream passage provided by the!Devil Canyon rapids.Until the Denali Highway was opened in 1957, the!upper reaches of the Susitna River were virtually inaccessible.Since 1957,the primary use of the upper Susitna River from Denali downstream to the confluence with the Oshetna River has been by hunters.Below the Oshetna River is a section of rapids which,while navigable by either an experienced kay a ker or jetboater,is not frequently attempted.Even if this section is successfully negotiated,there are no downstream take-outs for'jetboaters above Devil Creek,and either a long portage around Devil Canyon or a fly out are required by kayakers. -16- R2"11/10 28 6.0 DESTINATIONS 6.1 Cook Inlet to Talkeetna - .- - The major use of the Susitna river is by sport fishermen (Howe,1985). Other uses of the river are often tied into providing services for the fisherman.Therefore,the desti nations of almost all boaters are to the are~as where fishing is best.In the river below Talkeetna,this is restricted to streams and sloughs which enter the Susitna.The two most productive salmon fishing areas are the Deshka River and tributaries to the~Yentna River.These two areas a re major desti nations of most boaters. Th,e primary destinations for boaters using the Willow Creek landing were the~Desh ka River and Willow Creek itself,with some boaters also goi ng to the,Yentna River and Little Willow Creek later in the'season (Table 6.1). Destinations are closely related to the timing of salmon runs.Figure 6.1 illustrates the migrational timing of the five species of salmon found in the Susitna River.The Deshka River has a major run of king salmon in June, resulting in the overwhelming selection of the Deshka River as the primary destination in June.Later salmon runs are in the Deshka River,Willow Crl~ek,Little Willow Creek,other tributaries to the Susitna,and tributaries to the Yentna River,resulting in a wider diversity of destinations later in the summer.Many of the boats never leave Willow Cr4~ek. A similar pattern was noted for boaters leaving Susitna Landing (Table 6.2).The Deshka River was the primary destination in May and June, with Yentna River,Willow Creek,and Alexander Slough also visited. When later salmon runs reached other tributaries and when the hunting season started in September,the diversity of destinations increased. The breakdown of major destinations of boaters on the lower Susitna River is further illustrated in Table 6.3,with secondary destinations also included.Table 6.3 also illustrates the destination pattern based on the -17- -- - ..... R21/10 29 major sporting seasons of king salmon fishing,other salmon fishing,and hunting. 6.2 Talkeetna to Devil Canyon The~vast majority of boaters that use the access area at Tal keetna boat up the Talkeetna River (Table 6.4).Middle Susitna River usage has been recj~ntly dominated by Susitna River Study teams.Other boaters using the Middle Susitna River are primarily fishermen and guide services,with destinations of I ndian River,Portage Creek and Devil Canyon.A recent state land disposal along Indian River and the Susitna River above Indian River may generate increased traffic in this reach of the river. -6.3 Upstream of Devil Canyon - - - As previously described,little use is made of the river between Devil Canyon and the Oshetna River except for limited whitewater kayaking trips.No specific destinations have been identified along the reach above the Oshetna River,with boaters primarily using the river for access to hunting areas. -18- R21/10 30 7.0 7.1 USE OF RIVER Historical Use - - ,- ThE!historical use of the Susitna River is recounted in the BLM Navigation Study of Southcentral Alaska (Bureau of Land Management,1983).This report details the use of the river from its fi rst ascent by wh ite men in the spring of 1896,up to the present.The following accounts are excerpted from this report. ThE!early trips were made in hand-made riverboats,usually by prospectors or government agents.These often took on epic proportions, with some trips exceeding a year in length. Technical details of the early navigation of this river are best recounted in a letter of October 2,1898 in which W.G.Jack told of his trip up the Susitna River to Captain Edwin F.Glenn,who was then planning to send a detachment of soldiers up the Susitna River on a topographical survey. ".we used small boats and depended upon rowing and cordelling them.In my best judgment a properly constructed boat drawing not to exceed 2 feet of water can navigate this river (Susitna)from its mouth as far as the forks (Tal keetna),and from that point up the Middle Fork for a distance of about 37 miles,or to Indian Creek [River].The only obstacle to be overcome in this fork is a sand bar.They may not exist another season,but du ring this season it confined the cu rrent to a very narrow,swift chan nel.At no stage of water have I found th is river with a chan nel that did not contain sufficient water to float a vessel of the draft above men- tioned.The mean fall in this river from the forks to its mouth is about 3 feet to the mile.In the mai n fork [Middle Fork]the mean fall is about 7 or 8 feet to the mile.The current is about the same as that of the Missouri River,or from 4 to 5 miles per hour,in the main stream,and probably a mile (per hour)more in the fork.The -19- - -- - - R211 /1 0 31 difficulty in navigating this stream will be greater in descending than in ascending.The type of boat for th is stream must be a flat-bottomed,stern-wheel,with sufficient power to enable it to be checked quickly,especially in descending the river.The principal reason for this,aside from overcoming the current and handling the boat readily,is that the channels change frequently and qu ickly,and freshets bring down a great amount of dri"ftwood in the shape of large trees,which must be avoided.The changes in the channels are so easily,quickly,and frequently made that the same channel used in going up will not be used in coming down on the same trip.The total navigable distance,according to the above,is 119 miles,which a boat would have to travel at least 130 miles to overcome." Following these early explorations the belief was formed that the Susitna wa~;navigable for powerboats,at least up to Indian River.This was suc:cessfully put to the test in 1907.During the period from 1907-1910 propeller-driven barges made several trips to Indian River (Figure 7.1 and cover).These trips were limited to periods of high water.Their main purpose were to supply miners in the Valdez Creek area and to transport supplies for the building of the Alaska Railroad.Paddle wheel driven steamboats were also used on the river,but their destinations were usually limited to the lower 30 miles of the river (Figu re 7.2). Wh,en the Alaska Railroad was completed in the early 1920's,use of the Susitna River as a supply route came to an end.Since then the boating USE~of the river has been left to sportsmen and homesteaders. 7.2 Summer Use Present day use was documented during the summer of 1984 by an ADF&G user survey (Howe,1985)made of boaters exiting the Susitna River at the three main access points of Willow Creek,Susitna Landing,and Talkeetna (Figure 5.1).At all of these sites sporting use,with fishing being the dominant sport,is the prima ry pu rpose of the boaters. -20- - - -- - - - R21/10 32 Sport fishing was the main activity engaged in by boaters exiting at Willow Creek in 1984 (Tables 7.1 and 7.2).Du ri ng July and August,174 boats (78%)and 160 boats (71%),respectively,identified sport fishing as the main activity.Another 27 boats (12%)and 20 boats (9%)identified sport fish ing as a seconda ry activity du ring the same two months.Du ring September,29 boats (22%)identified hunting as the main activity,with another 75 boats (58%)identifyi ng it as a seconda ry acctivity.Du ri ng July through September,boaters exiting at Willow Creek indicated their main activities as sport fishing (342 boats -60%),transportation (56 boats -10%),hunting (32 boats -6%),and private supply (32 boats -6%). Sport fishing was also the main activity identified by boaters exiting at Susitna Landing (Tables 7.3 and 7.4)during May (328 boats -80%),June (783 boats -83%),July (252 boats -58%),and August (215 boats -61%). Private supply and transportation were also significant activities for each of the summer months.For May through September 1984,boaters exiting at Susitna Landing indicated their main activities as sport fishing (1,585 boats -60%),private supply (293 boats -'112%),and transportation (228 boats -10%). During Juy through September at Talkeetna"boaters indicated that sport fishing was the main activity (156 boats -39%),but that transportation (59 boats -15%),the Susitna study (54 boats -14%),and sightseeing (27 boats -7%)were also major activities (Tables:7.5 and 7.6).Talkeetna is the most upstream access point to the major study areas in the middle Susitna River,and is also the primary access point for guides taking sightseers to Devil Canyon. Not surprisingly,the major users of the river where those from the Municipality of Anchorage (Group 2,Chugiak to Girdwood),as seen in Table 7.7.Local residents (Groups 1 and 4)also frequently use the river.Most boaters indicated they planned to use the river many times du ring the summer (Table 7.8),with over 46%of those su rveyed at Susitna Landing planning to use it from 11-20 times. -21- R21/10 33 To help relieve the intense fishing and boating pressure on the Kenai River by Anchorage residents,the State of Alaska is planning to develop increased boat access to the Susitna River.A major component of the State's plan is development of the proposed Willow Creek State Recreation Area.The proposed recreation area is located along Willow Creek, accessible via the Parks Highway to the major population centers of Anchorage,Eagle River,and Wasilla.Facilities proposed for the park include an access road leading from the Parks Highway to the mouth of Willow Creek,development of trails and campgrounds,and construction of a boat launch on the Susitna River just downstream of the mouth of Willow Creek.This new access point will greatly increase the ease and convenience of boating on the lower Susitna River.The development of this recreation area,together with the increasing population of the Anchorage area,indicates increased usage of the lower Susitna River as a recreational resource. The Susitna River above Portage Creek sees only limited use.The steep gradient,high canyon walls,lack of access and take-out points,and heavy rapids at Vee Canyon and from Devil Creek to Devil Canyon limit recreational use below the Oshetna River primarily to whitewater kayakers. The rapids in the 12-mile reach from Devil Creek to Devil Canyon are considered world-class,and are navigable by a limited number of experts. If this 12-mile reach is not run,the only other ways out of the river are to be flown out,to portage around Devil Canyon,or to portage to Stephen Lake and go down the Talkeetna River. Above Vee Canyon,the primary use of the river IS by hunters during September.Access was very limited until construction of the Denali Highway.Statements by local residents eCole,1979)indicated that "95-100 percent of traffic on the river is in the first two weeks of September every year.Du ring that time .there mig ht be 30-35 boats on the river.Most of the hunters are after moose,but there are some caribou and brown bear hunters as well.According to Huttnen,among the boats there are air boats,canoes with props,r'iverboats with jet units and -22- ..... R21/10 34 props,large inboard jets with 307 Chevrolet engines and others".The river is deep enough above the mouth of the Tyone River to accomodate any conventional craft. 7.3 Winter Uses The Susitna River sees only limited use as a transportation corridor during the winter,with the primary use in the reach below the Parks Highway Bridge.Frequent open leads often make·snowmachine travel hazardous, especially upstream of Tal keetna.The Alaska Rail road parallels the river from Talkeetna to Gold Creek,providing ready access to this reach.The river upstream of Gold Creek is very remote and inaccessible except in the area of the Denali Highway,which is usually not maintained during the winter.The few people who overwinter near Denali occasionally snowmachine along this braided portion of the river. The areas around Susitna Station and the mouth of the Deshka River see the most frequent use.Several year-round residents live at Susitna Station.The Iditarod Trail also crosses the Susitna River at Susitna Station.The Desh ka Silver-King Lodge,at the mouth of the Desh ka River,stays open year-round,and is a popular destination for cross-country skiers,who must cross the Susitna River at about RM 42. -23- (~ - R21/10 35 8.0 NAVIGATION RESTRICTIONS 8.1 Cook Inlet to Talkeetna The lower portion of the Susitna River is braided,silty,and constantly changing.A deep main channel exists from Talkeetna to Cook Inlet.In most places this main channel has numerous side channels branching from it.Depth of water in these side channels is dependent on flow rate and channel morphology.Side channels navigable at high flow will sometimes dewater or have long shallow reaches at lower flows.At high flows, several routes are usually available to the boater to reach his destination. At lower flows,boaters may have to take a more circuitious route in order to have sufficient depth to navigate.High flows sometimes increase navigation hazards.During a flood,there are usually a large number of floating trees.Also,many familiar landmarks are covered by water and new channels are opened.The highly turbid water makes it difficult to determine the depth of water in the new channels and along the edges of gravel·bars. The boater's experience on the river and with his type of boat also determine navigation routes.Those who use the river often a re familia r with its characteristics under a variety of flow conditions.They also know'how their boat reacts,and what its limitations are.These boaters are familiar with the best routes for their particular craft,and may quickly react to varying conditions.Those boaters with less experience on the lower Susitna River often find it confusing at first,due to its broad floodplain and multiple channels.It is quite possible to select a channel which looks good at its entrance,only to find that it may rapidly become shallow with no place left to take the boat.As boaters gain more experience on a particular reach of river,tlheir navigation problems tend to decrease. At times,even experienced boaters may have navigation problems on the Susitna River.Large flood events tend to cause significant bed material -24- - - - R21/10 36 transport,with major channels sometimes shifting several hundred yards in a few days.Log and debris jams may block previously navigable channels and cause channel shifts.Gravel bars may have moved to new locations. Boaters have no option but to exit as gracefully as possible when they encou nter these new conditions. 8.1.1 Cook Inlet (RM 0)to Yentna River Confluence (RM 28) A deep channel exists from the Yentna River downstream to Cook I nlet.The major destination for boaters in this reach of river is Alexander Creek.During moderate-to-high flows,boaters often travel th rough Alexander Slough (Figu re 8,1),which is actually a major side channel west of the main channel.As flows drop, insufficient flow enters the channel at tlhe upstream end (RM 19)and Alexander Slough generally becomes unnavigable except for ai rboats. When this occurs,boaters have the options of either going through Powerline Slough at RM 6.5 (Figure 8.2)or else continuing to Cook Inlet and then going up the west channel.Use of Powerline Slough is common for residents of Susitna Station (Hawley,1984). Examination of aerial photographs indicates that Alexander Slough is navigable by jetboats at Susitna Station flows of 67,800 cfs,but that only airboats could navigate it at Susitna Station flows of 51,400 cfs. Numerous shifting sand bars exist in this side-channel. 8.1.2 Yentna River Confluence (RM 28)to Susitna Landing (RM 61) This reach of river is the most frequently used on the Susitna River, as it includes the major salmon fishing areas (of Willow Creek,Deshka River ,and Yentna River)and the major access points (Willow Creek and Susitna Landing).The reach has multiple channels separated by vegetated islands,and includes the segment known as Delta Islands (RM 51 to RM 42). -25- .- - -- .-. R21/10 37 Table 8.1 summarizes the navigational problems indicated in the 1984 ADF&G survey (Howe,1985).The su rvey indicated only whether navigational problems were encountered,but did not include either the severity of the problem or its location.At Susitna landing, boaters indicated more problems with debris and high velocities in May and June,with problems with bars becoming more prevalent in late summer when the flows decreased.Boaters at Willow Creek indicated more problems with bars and rocks.It is likely that many of these problems were encountered on Willow Creek itself,as boaters must travel along its narrow,winding cou rse for seven miles before reaching the Susitna River.The types of boats used changed during the summer,with airboats more commonly used late in the summer. locations of specific navigation probl,em areas in this reach were determined from examination of aerial photographs,from discussions with local residents,boaters,and ADF&G study crews,and from observations during aerial overflights and boafing trips.Only those problems concerned with either major channels or with access will be discussed.Many channels navigable at high flows may dewater at lower flows. During low flows at Susitna landing (mouth of Kashwitna River), boaters may encounter problems reaching the main channel when they attempt to go upstream into the Susitna side channel into which the Kashwitna River empties (Figure 8.3)..However,no problems are encountered when entering or leaving the downstream end of this channel.R&M hydrologists observed jet boats on the main channel at RM 60.8 on September 12,1984 (flow at Sunshine =22,700 cfs). Downstream of Susitna landing,the main channel is located in the braided segment on the west side of the floodplain.The channel can be easily followed,although some problems may be encountered when boaters attempt to take shortcuts thr·ough other channels.Three major cha n nels flow th rough the Delta Islands.Boaters from Susitna -26- .,... R21/10 38 Landing usually travel down the western chan nel,as it is the shorter and quicker route to the Deshka and Yentna Rivers.Jetboats were observed by R&M hydrologists at RM 52 ..5,RM 47.5,and RM 43.7 on September 12,1984,with average daily flow at Sunshine equal to 22,700 cfs.Although the center channel is sometimes used,it is generally narrower and shallower than the other channels.Since Willow Creek flows into the eastern channel,boaters commonly conti nue down it to the Desh ka River and beyond.Boats were observed at the mouths of Willow Creek and Little Willow Creek when flow at Sunshine was 17,800 cfs. Near RM 51,shifting gravel bars and falling trees create a navigation problem where the river enters the Delta Islands reach.The channel just upstream of the island at RM 51 (Figure 8,4)was navigable for most of 1983 and 1984,but a falling tree blocked it in September 1984,forcing boaters to use a shallow channel just upstream.This channel was navigable at a Sunshine!flow of 31,200 cfs by a propeller-driven riverboat which required 18 inches of water (Ellithorpe,1984). The Delta Islands are considered to end where the eastern and western channels meet at RM 42.5.A well-defined deep channel exists from this point past the confluence with the Deshka River (RM 40.5)to the confluence with the Yentna River (RM 28).Several jetboats were observed on the main channel along this reach by R&M hydrologists on September 27,1984,when the average daily flow at Sunshine was 17,800 cfs.Numerous side-channels branch off in this reach,but they do not provide access to any additional fishing areas. Kroto Slough branches off to the southwest as a side-channel at RM 40 (Figure 8.5).Two gravel bars control flow through this channel, one at the head of the side-chan nel at RM 40,and another at the head of the slough where it branches off from the side-chan nel and continues to the Yentna River.Kroto Slough provides limited access during high water to a number of remote parcels along its length. -27- -~-~~--~~--------- .- - - - R21/10 39 Flow is maintained in its lower reaches by several small tributary streams. 8.1.3 Susitna Landing (RM 61)to Talkeetna (RM 97) Only a small number of boaters appear to use this reach of river, with the possible exception of during hunting season.No major salmon spawning streams are located on the west side of the river. Several important salmon spawning streams,including Sheep Creek, Goose Creek,Montana Creek,Sunshine Creek,and Birch Creek,join the Susitna River or its side chan nels along the east ban k.The backwater zone at the mouth of Caswell Creek is also an important salmon fishing area.Except for Sheep Creek and Birch Creek,the mouth of each of the above streams can be reached by short walks from roads leading off the Parks Highway,limiting the need to boat to those areas. Sheep Creek empties into a side-channel at about RM 66 (Figure 8.6). Jetboats were observed up to RM 64.5 on this side-channel at Sunshine flows of 22,700 cfs.It appeared that they could continue to the confluence with Sheep C reek,although navigation past a gravel bar may have been difficult.Airboats would have had no problems. Birch Creek joins the Susitna side channel at about RM 88.2 (Figure 8.7).Travel down the side-channel past the gravel bars controlling flow may be difficu It at low flow,but access is feasible up the lower end of the side chan nel. Access can be gained to this reach of the river at Susitna Landing (RM 61),Sunshine (RM 83.8),or Tal keetna (RM 97).As previously mentioned,the Sunshine site does not appear to be frequently used. Jetboats were observed to be navigating this reach of the river at Sunshine flow of 22,700 cfs.The major navigational problems are in -28- - .... R21/1O 40 the braided sections of the river where numerous channels branch off.Jetboats and airboats should not have problems,but riverboats using propellers without a lift could encounter difficulties at low flows. 8.2 Talkeetna (RM 97)to Devil Canyon (RM 150) Access to this reach is prima rily from Tal keEitna.For most of the summer, boats leaving the Tal keetna River at RM 97 go upstream along the east side-channel to reach the mainstem of the Susitna River (Figure 8.8). However,th is .route becomes increasingly difficu It at low flows,and boaters sometimes boat downstream to where the channel joins the mainstem at RM 95,then continue up the Susitna River. Upstream of its confluence with the Chulitna River,the Susitna becomes more channelized with either a single chann'el or split channel morphology up to Devil Canyon.Numerous side channels exist which are navigable at high water,but which dewater at lower flows.The main channel is navigable by jetboat to Devil Canyon. Isolated large boulders exist in some portions of the channel (Figu re 8.9), but they are easy to navigate around.The only potential navigation problem area was identified by Janke (1982)as a broad shallow reach below Sherman at RM 128,where the main channel crosses the floodplain (Figure 8.10).This area was subsequently surveyed (R&M,1982c)and a deepwater channel found.This location was later navigated without problem by jetboat at a flow rate of 6,300 cfs (measured at the Gold Creek gage). Steve Mahay,local guide,has traveled th is reach of the Susitna River for nine years and has reported no navigational problems (Mahay,1984).He did comment that after a flood it is a bit more difficu It to read the river due to shifting gravel bars. -29- - R21/10 41 8.3 Devil Canyon (RM 150)to Devil Creek (RM 162) This is the steepest (gradient of 31 feet/mile)and most treacherous reach of the Susitna River,and is navigable only by expert whitewater kayakers at low-to-moderate flows.Access is either by helicopter or by floating down from the Denali Highway.In recent years,this reach has gained a reputation as one of the most difficu It whitewater ru ns in North America. The first successful kayak run was recorded in 1976.Since then,a handful of successful trips have been completed,mostly at flow rates less than 26,000 cfs at Gold Creek.A 22-foot jet boat attempted to run upstream through the canyon in 1982,but was quickly sunk. 8.4 Upstream of Devil Creek Although steep and swift,the river upstream of Devil Creek is navigable by most types of watercraft.Numerous rapids exist,but they are navigable.The most serious rapid is located at Vee Canyon,where several large standing waves occur.Upstream of Vee Canyon,the river is deep and relatively easy to navigate. -30- -----------------------,----,--_.,--------------------- - ,.,.. I R21/1O 42 9.0 WITH-PROJECT CHANGES IN FLOW REGIME Operation of the Susitna Hydroelectric Project will alter the flow regime below the projects,decreasing flows in the summer as water is stored to fill the reservoirs,and increasing flows·in the winter in order to meet the power demand.The weekly flow duration values for week 32 (May 6 - May 12)through week 52 (September 23 -September 30)are shown for gaging stations at Gold Creek,Sunshine,and Susitna Station.Three conditions are tabulated;natural;1996 load with Watana only operating; and 2020 load with both Watana and Devil Canyon operating.The flow duration values are those derived for the Case E-VI flow alternative (Harza-Ebasco,1984a),which is shown in TablE~9.1. The change in flow regime is most noticable at Gold Creek (Table 9.2). With -project flows a re less than natu ral flows under all conditions from week 35 to week 45,or from late May to mid-August.Maximum flows are sharply reduced,although ·the tables indicate that relatively high flows may occasionally occur in August and Septl~mber,when the reservoir is full.With-project flows are occasionally greater than natural flows,as seen for weeks 32-34 (early to mid-May)and weeks 46-52 (mid-August through September).Minimum weekly flow in the middle Susitna River during the open-water water season is 5,990 cfs in mid-May and late September,with flows of 7,990 cfs exceeded from June through August. Changes in flow are not as significant at Sunshine (Table 9.3)and at Susitna Station (Table 9.4),although patterns similar to those at Gold Creek occur.The Chulitna and Talkeetna Rivers enter the Susitna River upstream of the Sunshine,minimizing the impacts of flow regulation. Flows exceed 30,000 cfs at Sunshine under most conditions from early June to mid-August.After mid-August,low flows under with-project conditions are usually only slightly less than low flows under natural conditions,and in some cases exceed natural flows. -31- ..... - - R21/10 43 10.0 WITH-PROJECT CHANGES IN RIVER MORPHOLOGY Changes in river morphology will vary along the length of the river. Consequently,the expected changes will be described for each reach of river from the reservoi rs downstream to Cook Inlet. 10.1 Watana Reservoir Watana Dam is to be the fi rst project constructed.Du ring construction, little change in river morphology will occur except at the damsite itself, where cofferdams will divert all flow th rough two tu n nels on the north abutment.Tunnel No.1 will have its inlet above the river bed level and its outlet at the river bed level.Tunnel No.2 will have both the inlet and outlet below the river bed level.All river flows up to approximately 20,000 cfs can be passed solely through Tunnel No.2.Because of its lower elevation,Tunnel No.2 will also pass all sediment loads past the damsite.Consequently,no interruption in sediment load is anticipated,so no changes in downstream river morphology are expected. Once filling of the reservoir commences,the character of the river immediately upstream of the dam will change from a fast-flowing river with numerous rapids to a still-water reservoir.The reservoir will ultimately extend 54 river miles upstream,terminating 8 miles downstream from the confluence with the Tyone River,and will inundate the major rapids at Vee Canyon.Du ri ng project operation,the actual upstream extent of the reservoir will depend on the reservoir level. 10.2 Devil Canyon Reservoir After Watana Dam is constructed,but before Devil Canyon Dam is constructed,the river reach from RM 151 to RM 184 will tend to be shallower and na rrower than under natu ral summer conditions.Velocities will be less than under natural summer flows.In some places,especially in Devil Canyon,more rocks and boulders will be exposed. -32- --------------,-------,-----,-------------------- .- R21/10 44 When Devil Canyon dam is being built,the most significant impacts will be at the damsite,as the rapids at the upper end of Devil Canyon will be blocked off and approximately 1100 feet of the Susitna River between the upstream and downstream cofferdams will be dewatered . The major impact on this reach Canyon Reservoi r will be the free-flowing river into a reservoir. during filling transformation and operation of this reach of Devil from a 1'"'" I - 10.3 Devil Canyon to the Chulitna River Confluence During filling and operation of the Watana and Devil Canyon Reservoirs, the trapping of bedload and suspended sediment by the reservoirs will greatly reduce the sediment being transported by the Susitna River in the reach from Devil Canyon to the Chulitna River confluence.Analyses have indicated that channel degradation will be small in this reach,generally less than 0.3 feet,due to the large bed material.The reduced flood flows will be unable to transport as much or as large of bed material as under natural conditions.The estimated armoring sizes for with-project condition are considerably smaller than those for natural conditions because of the smaller dominant discharge (Harza-Ebasco,1984b).The Susitna River main channel in this reach will tend to become better defined with a narrower channel (R&M,1982a).The main channel river pattern will strive for a tighter,better defined meander'pattern within the existing ban ks.A trend towa rd chan nel width reduction by encroachment of vegetation will begin.Tributary streams will extend their alluvial fans into the river (R&M,1982a),with some agg radation expected downstream of the tributary mouths (Harza-Ebasco,1984b). Overflow into many of the side-channels will be significantly reduced by regulation of the summer floods.The backwater effects at the mouths of side channels and sloughs will be reduced.These factors will lead to vegetation encroachment in the side channels and sloughs. -33- - .-. I - ,- ...., - R21/1O 45 The chan nel cross-section obtained at the potential navigation restriction area at RM 128 is shown on Figure 10.1,together with summer flow levels for natural and with-project conditions.An aerial view of this reach at 7,500 cfs (500-1,500 cfs less than with-project flow conditions)is seen in Figu re 8.10. 10.4 Chulitna River Confluence to Cook Inlet Project effects on sediment transport in this reach will depend primarily on the change in the the bedload transporting capacity of the Susitna River below its confluence with Chulitna and Tal keetna Rivers.Under with-project conditions the reduction in summer flows from the Susitna River will result in a decrease of the total sediment discharge capacity at Sunshine to about 55 percent of that under natural conditions.With 80 percent of the total sediment load coming from the Chulitna and Talkeetna rivers,long-term agg radation can be expected.It is expected that aggradation will start at the mouth of the Chulitna River.Existing delta formation will further develop and extend towards the left bank below the confluence (Harza-Ebasco,1984b).The aggradation is not expected to be significant downstream of the Sunshine bridge.The estimates of aggradation are being refined,using the IALLUVIAL model developed by the Iowa Institute of Hydraulic Research. Downstream of the Susitna-Chulitna confluence,the frequency of occurrence of dramatic changes in river morphology will decrease under with-project conditions,resulting in a more stabilized floodplain,decreased number of subchannels,and increased veSletative cover.However,an extreme flood event generated by either the Chulitna River or Talkeetna River cou Id sti II cause significant morphologic changes.Project impacts on river morphology will decrease further downstream as more tributaries enter the Susitna.By the time the Yentna River enters,project effects on river morphology wou Id be extremely difficult to quantify. -34- ,~ - ...... R21/10 46 11.0 WITH-PROJECT CHANGES IN THERMAL AND ICE REGIMES Changes in the thermal and ice regimes downstream of the reservoirs are relevant to navigation primarily in determining the open-water season for boating and the ice-covered period for wi ntel"transportation.The periods· of most interest are therefore the freeze-up and breakup periods. Under natural conditions,frazil ice is first generated in the upper reaches of the Susitna River.This portion of the basin is higher,farther north, and in the continental climate zone,resulting in colder temperatures earlier in the winter.Until river water temperatures drop to OOC throughout the length of the river,the ice melts before reaching Cook In let.U!timately, sufficient ice is being contributed by the Susitna and its tributaries to form an ice bridge near RM 9,usually during a high.tide cycle. Formation of the ice bridge blocks the passage of ice to Cook I nlet,and the ice cover progresses.upstream as ice is added to the upstream edge . Depending on meteorological conditions,and on the formation of additional ice bridges on the lower Susitna River,the ice cover normally reaches Talkeetna from early November to early December.The ice front progression continues upstream of Talkeetna,_but at a slower rate due to the steeper gradient.The ice front reaches Gold Creek sometime between mid-December to mid-January.Ice cover formation between Gold Creek and Devil Canyon is usually by anchor ice dam and border ice growth. Upstream of Devil Canyon,ice cover formation is both by upstream prog ression from ice bridges and by border ice growth. Operation of the projects will result in water being released in fall and winter in greater volumes and at higher temperatures than occur under natu ral conditions.The reservoi rs wi II also trap the ice generated in the upper reaches.Consequently,freeze-up will be delayed by several weeks.Melt-out of the ice cover will occu r earlier.The actual timing of these events is dependent on the distance downstream from the reservoirs, meteorological conditions,and the discharge.Estimate of with-project ice-conditions have been made using the ICECAL simulation model -35- R21/10 47 (Ha rza-Ebasco, simu lations are Creek only. 1984).Those results are summarized below.The for the reach between the Chulitna confluence and Gold - - ..- .... Although ice contributions from the Susitna River above Talkeetna will be greatly reduced during the early freeze-up period,the assumption has been made that sufficient ice will be contributed by the Yentna,Chulitna, Talkeetna,and lower Susitna Rivers to form an ice bridge near RM 9 in late October,the same as under natu raj conditions.Based on this assumption,November 1 was selected as a representative date on wh ich the lower Susitna ice front would reach the Yentna confluence under with-project conditions (Harza-Ebasco,1984c:).The ICECAL model and related computations of tributa ry frazi I ice production were in itated on November 1 of each simulation year in order to estimate the time required to form an ice cover on the Susitna River up to the Chulitna confluence. Once the ice cover reached the Chulitna confluence,detailed modelling was conducted of ice cover progression on the Middle Susitna.The reservoir release temperatu re policy used in the simu lations attempted to match the natural stream temperatures incoming to the reservoir. When Watana is operating alone,the ice front is expected to reach the Chulitna confluence 2 to 5 weeks later than under natural conditions.A gradual spring melt-out above the Chulitna confluence will occur 5 to 7 weeks earlier than the natural mechanical breakup,and'will continue downstream of Tal keetna.Maximum upstream extent of the river ice cover during the simulated warm,average,and cold winters is expected t.o range from RM 124 to RM 142.The maximum total and sol id ice thicknesses are expected to be generally simila I'to those of natu ral conditions. When both Watana and Devil Canyon are operating,the ice front is expected to reach the Chulitna confluence 4 to 6 weeks later than under natu ral conditions.Completion of the spri n9 melt-out above the Chu Iitna confluence is expected 7 to 8 weeks earlier than the natural breakup,or by early to mid-March.The maximum extent to ice cover would range -36- - - R21/10 48 between RM 123 and RM 137.The maximum total and solid ice thicknesses are expected to be typically 1 to 2 feet less than those of natural conditions. -37- .- ..... ..- R21/1O 49 12.0 IMPACTS ON OPEN-WATER NAVIGATION 12.1 Watana Reservoir Since all flow will be diverted through tunnels during construction of Watana Dam,the only effect on navigation will be in the immediate vicinity of the dam and its diversion tunnels.The cofferdams will form an obstacle which will be difficult to circumvent.However,since use of this river reach is limited,the effect is expected to be minimal. Once impoundment of the reservoir commences,the character of the river immediately upstream from the dam will change from a fast':'flowing river with numerous rapids to a still-water reservoir.The reservoir will ultimately extend 54 river miles (87 km)upstream,terminating 8 miles (13 km)downstream from the confluence with the Tyone River,and will inundate the major rapids at Vee Canyon.The reservoir will make possible increased boat traffic to this reach of river by decreasing the navigational hazards through Vee Canyon.Reservoir water craft navigation will extend to November because of the delay in ice cover formation . 12.2 Devil Canyon Reservoir The reduced summer flows released from Watana Reservoir during its filling and operation could reduce the navigation difficulties between Watana and Devil Canyon du ring the summer months.However,the lower segment of this reach (from Devil Creek to Devil Canyon)will still consist of whitewater rapids suitable only for expert kayakers. During construction of Devil Canyon Dam,the reach from Watana Dam to Devil Canyon Dam will be navigable,at flows less than natu ral conditions. The rapids downstream of Devil Canyon will remain extremely difficult. The whitewater rapids at Devil Canyon will be eliminated because of construction activities. -38- ,.", - .- R21/10 50 During filling,the rapids upstream from Devil Canyon will be inundated and whitewater kayaking opportunities will be lost.Since the water surface level of the reservoir may be rising as much as 8 feet (2.4 m)per day during filling;the reservoir will be unsafe for boating.Downstream water levels may be slightly less than normal Watana operation levels,but this will not affect navigation because the change wHI be confined to the fall and early winter season. The Devil Canyon reservoir will transform the Devil Canyon rapids into calm water.This will provide recreational opportun ities for leisu re boaters,but will totally eliminate the wor'ld-class whitewater kayaking opportunities. 12.3 Devil Canyon to Chulitna River Confluence Summer flows downstream of the dam will generally be reduced from natural conditions during operation of either Watana alone or of Watana/Devil Canyon together,except du ring drought periods in late summer and fall (Table 9.2).Flows will exceed 7,990 cfs from June through early September,after which flows are gradually decreased to 5,990 cfs by the end of September.The only identified navigation problem in this reach,a channel cross-over near RM 128,has been successfully navigated at flows of 6,300 cfs. Navigation will not be significantly affected in this reach.In fact,several navigational benefits will occur.The navigational hazard of floating trees and debris will be eliminated in most years,due to the elimination or reduction of flood flows.Also,tu rbidity will significantly decrease, improving visibi lity. 12.4 Chulitna River Confluence to Yentna River Confluence Downstream of the Chulitna River confluence,the main channel is completely navigable at flows exceeding approximately 25,000 cfs,especially -39- ""'" - ,.,.. R21/1O 51 for jetboats and airboats.Below 25,000 cfs,specific areas may be difficult to navigate,such as the entrance to the west channel at the head of the Delta Islands (RM 51).The difficulty of navigation will be dependent on the boat draft,on recent changes in channel morphology,and on tree and debris jams.At least one deep water channel should exist from the main access points of Susitna Landing and Willow Creek to the main destinations of the Deshka and Yentna Rivers. The flow duration data in Table 9.3 indicates that 25,000 cfs will be exceeded 100 percent of the years for week 37 (June 10 -June 16) through week 45 (August 12 -August 18),and at least 90%of the years from week 46 (August 12 -Augut 18)through week 48 (Augl.Jst 26 - September 1).Minor difficulties may exist in this reach during late May to early June and during September.In September,with-project flows will be very similar to those under natural conditions.Any navigational problems experienced during September would also have been experienced under natu ral conditions. 12.5 Yentna River Confluence to Cook Inlet The primary destination in this reach is Alexander Creek.During high flows,boaters often use Alexander Slough.At lower flows,numerous sand bars make Alexander Slough difficult to navigate for jetboats,so boaters then either go th rough Powerli ne Slough or down the east channel to Cook I nlet,then back up the west channel.The flow rate at which jet- boaters no longer use Alexander Slough has:not been precisely defined, but based on the examination of aerial photog raphs,it is estimated to be about 60,000 cfs at Susitna Station.Under with-project conditions,this flow value is exceeded about 75 percent clf the years during week 35 (May 27 -June 2),90 percent of the years for weeks 36 and 37 (June 3 -June 16),100 percent of the years from week 38 (June 17 - June 23)to week 46 (August 12 -August 18),and 90 percent of the years for weeks 47 and 48 (August 19 -Septembel·1).During September,flow duration data for natural and with-project conditions are almost identical. -40- R21/10 52 Based on the above flow du ration data,the effect of the project on navigation through Alexander Slough will be minimal.For the period June 3 -June 16,it is estimated that navigation problems through Alexander Slough due to project operation would occu r about 3 yea rs out of 34,or 10 percent of the years.No problems are anticipated from mid-June through September which would not have occurred under natural conditions.When Alexander Slough is too shallow to navigate,boats may use Powerline Slough. -41- ~- .... R21/10 53 13.0 IMPACTS ON WINTER TRANSPORTATION Project effects on winter transportation are expected to be minimal.Much of the existing winter use of the river is downstream of Talkeetna.The ice cover formation in the lower reach of river,where much of the winter transportation occurs,is not expected to be s,ignificantly delayed.The ice cover is expected to progress to the Chulitna confluence 2 to 5 weeks later than under natural conditions when only Watana is operating,and 4 to 6 weeks later when both Watana and Devil Canyon are operating.Melt-out will occur several weeks earlier than under natural conditions.This will shorten the winter travel period around Talkeetna.Travel restrictions due to open leads in the ice cover will continue to occur. Between Talkeetna and Devil Canyon,there will be a delay in ice cover formation,and open water will exist for many miles downstream of the projects.However,travel in this reach is limited at present due to numerous open leads and to the presence of the Alaska Railroad adjacent to much of the river,so the affect on winter transportatioh patterns will be minimized. Winter travel in the reservoir areas is expected to improve.Numerous open leads presently occu r,and the river flows th rough a steep canyon. Once the reservoirs are filled,a solid flat ice surface will exist much closer to the top of the canyon.Due to the presence of the project camp, winter travel on this reach of river may significantly increase over existing use patterns. -42- _______m""""*'9"""""""'_~,_ R21/10 54 14.0 BIBLIOGRAPHY Alaska Depa rtment of Fish and Game,Susitna Hyd ro,Resident J uven i Ie and Aquatic Habitat Crew,1984.Personal communication on routes of travel. Alas ka Department of Natu ral Resou rces,Division of Pa rks and Recreation, 1984.Master plan for the proposed Willow Creek State Recreation Area. Alaska Power Authority,1983.Application for License for Major Project, Susitna Hydroelectric Project.Volume 5A.February 1983.Prepared by Acres-American,Inc. "... Arctic Environmental I nformation and Data Center, Geomorphic change in the Devil Canyon to Talkeetna Susitna River since 1949,submitted to Harza-Ebasco Ventu re,prepared for Alaska Power Authority,May. 1984 (draft). Reach of the Susitna Joint Bureau of Land Management,1983 (draft).Southcentral Alaska Navigation Study. Cole,Terrence,1979.The History of the Use of 'the Upper Susitna River.Indian River to the Headwaters,Alaska Department of Natural Resou rces. Harza-Ebasco Susitna Joint Venture,1984a.Evaluation of Alternative Flow Requirements,prepared for Alaska Power Authority.Document No. 2430,November. Ha rza-Ebasco Susitna Joint Ventu re,1984b.Reservoi r and River Sedimentation,Susitna Hydroelectric Project,preapred for Alaska Power Authority,April. -43- .-.., ,~ ..... - - R21/10 55 Harza-Ebasco Susitna Joint Venture,1984c.Instream Ice Simulation Study,prepared for Alaska Power.Authority.Document No.1986, October . Harza-Ebasco Susitna Joint Venture,1985 (dr-aft).Stream Flows and Flow Duration Curves at Watana,Gold Creek,Sunshine and Susitna Station for Watana Only Operation in 1996 and 2001,Volume 2 -Appendix E, prepared for Alaska Power Authority,February. Harza-Ebasco Susitna Joint Venture,1985 (draft).Stream Flows and Flow Duration Curves at Watana,Gold Creek,Sunshine and Susitna Station for Watana Only Operation in 1996 and 2001,Volume 4 -Appendix E, prepared for Alaska Power Authority,Februa ry . Hawley,Butch,1984.Personal communication,August 22. Howe,Allen L.,1985.A Survey of Boaters Exiting at the Susitna Landing;Talkeetna Boat Launch and Airstrip;and Willow Creek during 1984.Alaska Department of Fish and Game,Division of Sport Fish ing.March. Jan ke,Paul,1983.Alaska Department of Natu ral Resou rces,Division of Land and Water Management,Water Management section.A Preliminary Analysis of Potential Navigational Problems Downstream of the Proposed Hyd roelectric Dams of the Susitna River.Ma rch. Knik Kanoers and Kayakers,1983.The Eddy Line.Susitna River at Devil Canyon,Runs as of September 27,1982.February. Mahay,Steve,1984.Personal Communication,August 27. R8-M Consultants,Inc.,1982a.River Morphology,Susitna Hydroelectric Project,under contract to Acres American,Inc.,prepared for Alaska Power Authority,January. -44- ,~ - ~\ R21/10 56 R&M Consultants,Inc.,1982b.Hydraulic and Ice Studies,Susitna Hydroelectric Project,preapred for Alaska Power Authority,March. R&M Consultants,Inc.,1982c.Low Water Boat Navigation,Susitna River at Mile 128.Memo.November. Weber,Sepp,1976.Wild Rivers of Alaska.Alas ka Northwest Publ ishing Company.pp.71 and 83. -45- TABLES R21/10 62 TABLE 3.1 SUSITNA RiVER REACH DEFIN ITIONS -- Average River Mile Slope RM 149 to 144 0.00195 RM 144 to 139 0.00260 RM 139 to 129~5 0.00210 1"'" Predomlnent Channel Pattern Single channel confined by valley walls.Frequent bedrock control points. Spilt channel confined by valley wall and terraces. Spilt channel confIned occasionally by terraces and va I ley wa I Is.Me I .0 chan- nels.side channels and sloughs occupy va I I ey bottom. -RM 1\9 to 104 RM 104 to 95 0.00173 0.00153 0.00147 Spilt channel with occasional tendency 10 braid.Main channel frequently flows against west valley wall.Subchannels and s loug hs occupy east f loodp I a In. Single channel frequently Incised and occasIonal Islands. Transition from spilt channel to braided.Occasionally bounded by terraces.Braided through the con- fluence with Chulitna and Talkeetna Rivers. RM 95 to 51 0.00105 RM 61 to 42 0.00073- RM 42 to 0 0.00030 !""" R&M (1982A) - 47 Braided with occasional confinement by terraces. Combined patterns;western floodplain braided,eastern floodplain spilt channel. Spilt channel wIth occasIonal tendency to braid.Deltaic distributary channels begin forming at about RM 20. ,"···l M18/29 2 -}"}1 )l .)J ]t )1 l }l J } TABLE 3.2 PERIODS OF RECORD FOR GAGING STATIONS Station Name USGS G~ge Susltna Number River Mile 0/"8lnage 2Area(mf ) Per fods .of Record I I 2Streamflow(Continuous)Water Quality Aoencv Susltna River nr.Denali I 15291000 Susitna River nr.CantwEll I (Vee Canyon)I 15291500 Susltna River nr.Cantwell ' - (Vee Canyon) Susltna River nr.Watana Damslte'- 290.8 223.1 223.1 182.2 3 950 4,140 4,140 5,180 5/57-9/66,11/68-Present 5/61-9/72,5/80-Present 6/80-Present 1957-66,1968-69,1974-Present I USGS (6/30/82) 1962-72,1980-Present(7/27/82)I USGS 1980-81 I R&M Consult. I R&M10/80-12/81 Consult. Susltna River at Gold Creek ' - Susltna River at Gold Creek I 15292000 ~Susltna River at Sunshine 15292780 136.6 136.6 ,83.9 6.160 6,160 11,100 8/49-Present 5/81-Present 1949-58,1962,1967-68,1974-Presentl USGS (9/16/82) 1980-Present(10/14/82)I R&M 1971, 1975, 1977,1981-Present (10/13/82) Susltna River at Susltna Station I 15294350 Mac!aren River nr.Paxson I 15291200 Chulitna River nr.Talkeetna I 15292400 Talkeetna River nr.Talkeetna I 15291500 Skwentna River nr.Skwentna I 15294300 Yentna River nr.Susltna Station I 15294345 Notes: 25.8 259.84 498.0 97.04 28.0 5 428.0 19,400 280 2,570 2,006 2,250 6,180 10174-Present 6/58-Present 2/58-9/72,5/80-Present 6/64-Present 10/59-Present 10/80-Present 1955,1970,1975-Present(10/5/82) 1958-61,1967-68,1975 1958-59,1967-72,1980-Present (6/3/82) 1954,1966-Present(10/14/82) 1959,1961,1967-68, 1974-75, 1980-81 1981-Present (8/11/82) USGS USGS USGS USGS USGS USGS I.AI I streamflow gage stations are currently active.however.flow data Included In this document Is through September 1981. 2."Present"In perIods of record Indicates station Is active as of January 1983.A date after "Present"Indicates the most recent data available. 3.Watana continuous water quality monitor was Installed at river mile 183.0. 4.River mile at trlbutary's confluence wIth Susltna River. S.River ml Ie at Yentna-Susltna confluence. Source:USGS and R&M '--1M18/29.1 --1 1 "~I 1 )J 1 -J j J -~j j TABLE 3.3 fiLLED STREAMfLOW SUMMARY,SUSITNA RIVER STATIONS oJ::> \.D Stl!l tlon Denell l:cntwe II Watanll Dev II Canvon Gold Creek SunshIne susltna Maclaren Chulitna T81keetna Skwentnll Oct M8)(2,165 ...A~'"6,458 7.518 8,212 18,555 58,640 734 9,314 4,438 7,254-',"f' MeM 1,165 3,149 4,513 5,312 5;757 13,906 .3 I,102 4i8 5,040 2,720 A 'l.?Q...,..,-, Min 528 1,638 2 403 2,867 3 124 18,593 15,940 249 2,898 1,450 1 929 Nov Mal(878 2,487 3,525 3,955 4,192 9,400 31,590 370 3,277 1,786 4,195 Mean 500 1,460 2,052 2,383 2,568 6,104 13,361 182 2,083 1,209 1,867 Min 192 780 1,021 1,146 I 215 3,978 6 606 95 1,236 765 678 Dec Mal(575 1,658 2,259 2,905 3,264 6,137 15,081 246 2,143 1,239 2,871 Mean 315 951 1,405 1,652 1,793 4,249 8,426 117 1,487 846 1,295 Min 146 543 709 810 866 2 650 4,279 49 891 515 624 Jan Mal(651 1,694 1,780 2,212 2,452 4,739 12,669 162 1,673 1,001 2,829 Mean 248 850 " 157 1,352 1,463 3,550 7,971 99 1,288 682 1,068 Min 85 437 619 687 724 2,218 5,032 44 974 459 600 Feb Mal(422 1,200 1,560 1,836 2,028 4,057 11,532 140 1,414 805 1,821 Mean 206 706 979 1,147 1,243 3,009 7,117 81 1,092 568 911 MIn 64 426 602 682 723 2,082 4,993 42 820 401 490 Mar Max 290 1,273 1,560 1,779 1,900 3,898 9,193 121 1,300 743 1,352 Meon 192 659 898 1,042 1,123 2,683 6,397 74 979 491 826 Min 42 408 569 664 713 2,013 4,910 36 738 379 522 Apr Max 415 1,702 1,965 2,405 2,650 5,109 12,030 145 1,600 1,038 2,138 Mean 231 835 1,113 1,282 1,377 3,257 7,242 86 1,194 573 1,088 Min 43 465 609 697 745 2 205 5,531 50 700 371 607 May Mal(4,259 13,751 15,973 19,777 21,890 50,302 94,143 2,131 20,025 8,840 .22,370 Mean 2,306 7,473 10,398 12,230 13,277 27,955 61,376 832 9,519 4,150 8,555 Min 629 1,915 2.857 3,428 3,745 8,645 29 809 208 2,355 1,694 1 635 June MllX 12,210 34,630 42,842 47,816 50,580 110,073 176.219 4,297 40.330 19,045 40.356 Mean 7.532 17.567 22,913 25.938 27,658 63,810 123,830 2.888 22.892 11,416 18.462 Min 4 647 9 909 13,233 14,710 15.500 39 311 67,838 1.751 15,587 5 207 10,650 JUly MllX 12.110 22,790 28,767 32.388 34,450 85,600 181.400 4,649 35.570 15,410 28,620 Moan 9.688 16,873 20,778 23.101 24,383 64,538 134,130 3,241 27.044 11.118 16,997 Min 6 756 12,220 14,844 15,651 16,100 45,267 102,121 2 441 20 820 7,080 11 ,670 j 1 J )J 1 )~.J 1 J I )1 1 j ) M18/29 1 TABLE 3.3 FILLED STREAMFLOW SUMMARY,SUSITNA RIVER STATIONS -Continued Lno StatIon Denali Cantwell Watana Dev II Canyon Gold Creek Sunshine Susltna Maclaren Chulitna Talkeetna Skwentna Yrs.of Record Aug Max •..,.",,'In .....'11 .....:n 31,435 35,270 38,538 64,940 159,600 4,122 33,670 16,033 20,590.-',UIU "",/UU Mean 6,431 14,614 18,431 20,709 21,996 56,642 112,651 2,644 22,732 10,459 13,335 Min 3,919 6 597 7.772 8.484 8.879 24.656 62 368 974 11.300 3.767 7.471 Sep Max 6,955 12,910 17 ,206 19,799 21,240 53,703 104,218 2,439 23,260 10,610 13,371 Mean 3,334 7,969 10,670 12,276 13,175 32,169 66,790 1,167 11,956 6,084 8,371 Min 1.194 3,376 4.260 4 796 5.093 14,268 34.085 470 6.424 2,070 3.783 Ann Max 3,651 7,962 9,833 10,947 11.565 28,226 63.159 1,276 12.114 5,276 10,024 Mean 2.885 6,184 7,986 9,084 9,703 23,611 46,873 998 9,045 4,226 6,622 Min 2.127 4.159 4.712 5.352 5.596 14.355 31,426 693 .6.078 2.233 4,939 Notes:1.Based on 32 years of record. 2.Gold Creek data are not filled since 32 years of record are available. 3.Sunshine dIscharge for WY1980 and Oct-Apr WY1961 were computed from Gold Creek,Talkeetna,and Chulitna discharges for the same period. Acres (1983) I r- J Table 4.1 Boat draft by exit location,1984.a ,b ----------,---------------------------------------------- J ~Shallow Medium Deep Exit :~onth/-------------------- Location Season Boats %Boats %Boats %Total )-----..-_._._------------------------------------------- Susitna :~ay 203 54 146 39 29 7 378 Landing Jun 426 48 372 42 90 10 888 ,~Jul 224 53 147 35 53 12 424 I Aug 189 56 117 35 30 9 336 Sep 201 46 207 47 33 7 441 Overall 1,243 50 989 40 235 10 2,467 I -. Kings 676 50 549 41 128 9 1,353 Other fish 566 51 439 40 105 9 1,110 1 ~. Talkeetna Jul 98 89 4752 1 1 188 Aug 88 60 56 39 1 1 145 I Sep 55 87 8 13 0 0 63 Overall 241 61 153 39 2 1 396 ....Other fish 241 61 154 38 3 1 398 I"""Willow Jul 159 72 62 28 0 0 221]Creek Aug 181 82 38 17 3 1 222 Sep 107 86 15 12 2 2 124 ,.....Overall 447 79 115 20 5 1 567 )Other fish 418 80 102 19 5 1 525 ----------------------------------------------------------- I""'"a under 4.1"Medium:4.1-8.011 over 8.011 J Shallow:Deep: b The numbers presented are estimates. ~ I Howe (1985) J il -I ,.-. J I ~A I 51 i-- __.............IIIIIiIIIIllIM .....~.......~.........--..-._ ~"J 1 1 "1 )1 1 1 1 ))} aTable4.2 Boat class by exit location.1984. --------------------------------------------------------------------------------------------- Air Inboard Outboard Outboard Boat Canoe Jet Jet Prop Other Exit Month/------------------------------------------- Location Season Boats %Boats %Boats %Boats %Boats %Boats %Total --------------------------------------------------------------------------------------------- Susitna May 4 1 4 1 153 38 216 53 27 7 0 0 404 Landing Jun 8 1 6 1 333 36 500 53 78 8 9 1 934 Jul 7 2 2 1 205 47 191 44 27 6 0 0 432 Aug 7 2 0 0 150 42 172 49 25 7 0 0 354 Sep 22 4 2 1 167 33 253 51 56 11 1 0 501 Overall 48 2 14 1 1.008 38 1.332 51 213 B 10 0 2.625 Kings 15 1 10 1 532 37 761 53 107 7 9 1 1.434 Other fish 32 3 4 0 476 39 572 47 105 9 1 2 1.190 Talkeetna Jul 0 0 0 0 135 72 52 27 1 1 0 0 188 U1 Aug 0 0 0 0 104 72 39 27 1 1 0 0 144(\J Sep 0 0 0 0 45 70 19 30 0 0 0 0 64 Overall 0 0 0 0 284 72 110 28 2 1 0 0 396 Other fish 0 0 0 0 284 71 110 28 3 1 0 0 397 Willow Jul 131 60 1 1 22 10 64 29 0 0 0 0 218 Creek Aug 131 58 0 0 26 12 66 29 3 1 0 0 226 Sep 100 81 0 0 0 0 21 17 2 2 0 0 123 Overall 362 64 1 0 48 8 151 27 5 1 0 0 567 Other fish 350 62 0 0 48 9 149 26 5 1 0 2 552 --------------------------------------------------------------------------------------------a The numbers presented are estimates. Howe (1985) -------_._--------------------------------------~-_._--- Table 6.1 First destinations for boaters exiting ataWillowCrE~ek,1984. Boats %Boats %Boats %Boats % 53 567 100 13 2.3 1 0.2 191 33.7 1 0.2 5 0.9 24 4.2 1 0.2 4 0.7 1 0.2 3 0.5 301 53.1 22 3.9 Overall 100 Sep 4 3.5 1 0.8 55 44.2 1 0.8 4 3.4 19 15.2 1 0.8 o 0 o 0 1 0.8 27 21.7 11 8.6 100 124 3.6 o 24.8 o 0.5 2.3 o 1.8 005 0.9 61.3 4.5 Aug 0.5 8 o 0 36.7 55 o 0 o 1 o 5 o 0 o 4 o 1 o 2 62.4 136 005 10 Jul 221 100 222Total First: Destination Howe (1985) a The numbers presented are estimates. Alexander Slough 1 Caswell Creek 0 Deshka River 81 Flathorn 0 Kroto Slough 0 L.Willow Creek 0 Portage Creek 0 Sheep Creek 0 Susitna L~Lnding 0 Susitna Station 0 Willow CrE~ek 138 Yentna River 1 I- I, I I- I- I- Ii t- Ii J~ Ir- I- I J I~ j: t- tr aTable6.2 FirS1:destinations for boaters exiting at Susitna Landing,1984. ---------------.----------------------------------------------------------------- May Jun Jul Aug Sep Overall First ---------------------------- ------- Destination Boats %Boats %Boats %Boats %Boats %Boats % ....IliiliIW MliIilIIirI IIMIW ..IMW ~IIIIIMIII ~~.............IIIIiIIIiIIIA ~......,~ '1 --1 --._j '~1 1 )J I ]~-]}1 i D Table 6 b3 First destinations for boats by exit location for boats engaged in sport fishing, 1984.a , --------------------~=---~----------------------------------------------------------- Susitna Landing Talkeetna Willow Creek ---------------------------------------------------- Month!First Main Secondary Main Secondary Ma:f,n Secondary Season Destination --------------- -------------------------------- Boats %Boats "I Boats %'Rnnf"c %Boats %Boats %'0 _...............- ------------------------------------------------------------------------------------- May Deshka River 290 91 6 27 Yentns'River 13 4 16 73 Alexander Slough 9 3 0 0 Others 7 2 0 0 Jun Deshka River 628 81 41 51 Yentna River 78 10 31 39 Alexander Slough 18 2 1 1 Willow Creek 115 6 3 4 l.h Others 9 1 4 5 11I Jul Deshka River 178 71 33 41 0 0 0 0 53 30 15 60 Yentna River 28 11 40 50 0 0 0 0 0 0 0 0 Alexander Slough 4 2 5 6 0 0 0 0 1 1 0 0 Willow Creek 33 13 0 0 0 0 0 0 120 69 10 40 Talkeetna River 0 0 0 0 33 100 28 90 0 0 0 0 Others 9 4 2 3 0 0 3 10 0 0 0 0 Aug Deshka River 95 44 21 31 0 0 0 0 41 26 4 21 Yentna River 19 9 40 60 0 0 0 0 2 1 0 0 Alexander Slough 4 2 1 1 0 0 0 0 1 1 0 0 Sheep Creek 36 17 3 4 0 0 0 0 4 3 0 0 Willow Creek 53 25 2 3 0 0 0 0 108 68 15 79 Talkeetna River 0 0 0 0 83 80 0 0 0 0 0 0 Birch Creek 0 0 0 0 13 13 0 0 0 0 0 0 Others 7 3 0 0 8 8 1 100 4 3 0 0 -..,--]--,-·1 .-]~--)--....~........IIIIilIW IIIlIIIIi ..MIMI Mit )-'1 "--1 ) Table 6.3 (Continued) ------------------------------------------------------------------------------------- Susitna Landing Talkeetna Willow Creek Main Secondary Main SecondaryMonth/ Season First Destination Boats %Boats %Boats %Boats % Main Secondary Boats %Boat % Sep Deshka River Yentna River Talkeetna River Willow Creek Others 4 57 7 o 0 19 000 1 14 1 2 29 14 17 46 o 2 34 o o 18 o 1 o 0 o 0 95 0 o 0 5 1 o o o o 100 1 1 o 6 o 13 13 o 75 o 10 50 o 0 o 0 2 10 8 40 U1 0'1 King Deshka River 949 Yentna River 102 Alexander Slough 27 Willow Creek 60 Others 16 Other Deshka River 245 Fish Yentna River 36 Alexander Slough 8 Sheep Creek 40 Talkeetna River 0 Birch Creek 0 L.Willow Creek 4 Willow Creek 72 Others 8 82 50 9 52 2 3 5 3 1 3 59 58 9 94 2 5 10 7 o 0 o 0 1 1 17 3 2 10 45 47 3 3 3 33 0 53 0 3 0 4 0 o 134 o 13 1 0 2 0 6 10 o 0 o 0 o 0 o 0 85 28 8 0 o 0 o 0 6 5 o 83 o 3 o 2 o 4 85 0 o 0 o 3 o 234 15 1 25 1 1 1 o o 1 71 o 29 46 o 0 o 0 o 0 o 0 o 0 7 11 26 41 1 2 a The numbers presented are estimates.Missing data are indicated by --. b 'Main'indicates sport fishing was the main activity,'Yes'indicates secondary involvement in sport fishing. Howe (1985) Table 6.4 First destinations for boaters exitin§ at the Talkeetna boat launch or airstrip,1984. ----------,---------------------------------------------- Birch Creek 6 3.0 18 12.3 2 3.3 26 6.6 Chase 0 0 6 4.0 10 16.8 16 4.1 Chulitna River 7 3.7 0 0 4 6.9 11 2.8 Curry 1 0.7 0 0 1 1.7 2 0.5 Devil Canyon 1 0.7 0 0 0 0 1 0.3 Gold Creek 33 17.4 10 6.9 4 7.1 47 12.0 Indian Ri;ver 0 0 1 0.9 0 0 1 0.3 Hi 232 AK RR 16 8.6 0 0 4 7.1 20 5.1 Portage Creek 0 0 1 0.9 5 8.7 6 1.5 Sunshine 1 0.7 3 2.0 2 3.5 6 1.5 Talkeetna River 122 64.4 99 69.2 24 39.7 245 62.7 Trapper Creek 0 0 3 1.9 0 0 3 0.8 Whiskers Creek 1 0.7 3 L9 3 5.2 7 1.8 Total 188 100 144 100 59 100 391 100 ---------,--------------------------------------------- a The numbers presented are estimates. Howe (1985) 57 Boats %Boats %Boats %Boats % OverallSepAugSuI First Destination I ""'" I - 1.- J J ~ I ,~ J !""'" I ~ I ,~ I j ~ )-, I ,- I J ~ 1 I -I ) j~ j- j l i j Jl.-Ii f t- j r.) -j, ~ j ..... j ~ j """I Table 7.JL Percent of boats by activity and month for boatsl exiting at Willow Creek,1984.a --------------------------------------------- Responseb Activity Category .July Aug Sept Overall ---------_.------------------------------------.--- Sport Fishing Main 78 71 6 60 No 10 20 77 29 Yes 12 9 16 12 Trapping Main 0 0 0 0 No 100 100 100 100 Yes 0 0 0 0 Hunting Main 0 1 22 6 No 100 99 33 82 Yes 0 0 58 13 Commercil'l1 Main 0 0 0 0 Fishillg No 100 100 100 100 Yes 0 0 0 0 Commerci.al Main 0 0 1 0 Supply No 100 100 99 100 Yes 0 0 0 a Private Main 3 9 3 6 Supply No 95 90 94 95 Yes 2 a 3 2 Transportation Main 8 9 13 10 No 82 83 84 83 Yes 9 8 3 8 Camping Main 0 1 0 1 No 72 80 35 67 Yes 28 19 65 32 Sight Seeing Main 3 2 3 3 No 88 91 93 90 Yes 8 7 4 7 Mining Main 0 0 0 0 No 100 100 100 100 Yes 0 0 0 0 Susitna Study Main 0 1 0 0 No 100 99 100 100 Yes 0 0 0 0 Other Activity Main 7 3 3 5 No 92 95 95 94 Yes 1 2 2 2 --------.--------------------------------------------- a Tbe numbers presented are estimates. bRespondents indicated whether an activity was the main ac:tivity (Main),a secondary activity engaged in (Yes),or an activity they did not participate in (No)• Howe (1985) 58 -----------------_._----------------------------- 59 Howe (1985) Table 7.2 Number of boats by activity and monthaforboatsexitingatWillowCreek,1984. 8 342 96 165 20 67 o 1 125 572 o 0 29 32 26 471 75 75 o 1 125 572 o 0 1 2 124 570 o 1 4 32 118 533 4 9 16 56 104 473 4 43 o 3 44 386 80 184 4 16 115 516 5 40 o 0 125 573 o 0 o 2 125 571 o 0 4 26 119 540 2 9 174 160 23 46 27 20 1 0 223 224 o 0 1 2 223 222 o 0 1 0 223 224 o 0 1 0 223 223 o 1 7 21 213 202 4 1 19 21 184 185 21 18 1 2 161 181 62 42 7 5 198 203 19 16 o 0 224 224 o 0 o 2 224 222 o 0 15 7 206 215 3 4 bResponse Category July Aug Sept Overall a The numbE~rs presented are estimates. b Respondents indicated whether an activity was the main activity (Main),a secondary activity engaged :In (Yes),or an activity they did not participate in (No). Mining Commercial Suppl)7 Activity Commercial Fishing Trapping Camping Private Supply Hunting Sport Fishing Main No Yes Main No Yes Main No Yes Main No Yes Main No Yes Main No Yes Transportntion Main No Yes Main No Yes Sight SeeJlng Main No Yes Main No Yes Susitna Study Main No Yes Other Act:lvity Main No Yes I 1 I- I I I I~ I I~ I~ I~ I I I I ""'"I J,-I I ji J,- Table 7.3 Percent of boats by activity and month.aSusitnaLcmding.1984.. j ------.--.-----------------.----------.--------.-----.-- bResponse J-Activity Category May June July Aug Sept Overall --------.._-------------------------------------------- Sport Fishing Main 80 83 58 61 1 60 No 15 8 23 21 90 29j~Yes 5 9 19 19 8 11 Trapping Main 0 0 0 0 0 0 No 99 100 100 100 100 100 j Yes 1 0 0 0 0 0 Hunting Main 4 1 0 0 3 2 No 96 99 100 99 16 83 j~Yes 1 0 0 1 81 16 Commercial Main 0 a 0 0 0 0 Fishing No 100 100 100 100 100 100 Yes a a a a a a j Commercial Main 1 1 3 1 1 1 Supply No 99 99 97 99 98 98 Yes a 1 a a 1 a-Private Main 2 11 19 23 10 12jSupplyNo988576748383 Yes 0 5 5 3 7 4 Transport,ation Main 10 10 11 9 8 10jiNo897882839084 Yes 1 12 7 7 2 6 Camping Main a 1 1 1 a 1J,No 66 62 66 72 38 60 Yes 34 37 33 26 62 39 Sight Seeing Main 2 1 2 3 1 2.....No 94 90 95 93 97 93IYes493 4 2 5 Mining Main 0 a a a a a I"""No 100 99 100 99 100 100I'Yes 0 1 a 1 a a Susitna Study Main a a 2 1 1 1 No 100 99 98 98 98 99I:Yes a 1 a a a a Other Activity Main 5 2 3 3 3 3 No 93 90 97 96 96 94-Yes 1 8 a 1 1 3tJ -------------------------------------------------------~~e numbers presented are estimates. I bRespondents indicated whether an activity was the main activity (Main),a secondary activity engaged in (Yes), ~or an activity they did not participate in (No). j Howe (l985) J ~ ,j: 60 Table 7.4 Number of boats by activity and month,SusitnaaLanding,1984. Activity bResponse Category May June July Aug Sept Overall Mining Hunting Camping Trapping 1,585 765 293 2 2,628 4 39 2,183 417 3 2,353 o 27 2,322 10 293 1,970 100 228 1,998 152 17 1,589 1,030 44 2,458 132 o 2,352 6 24 2,328 7 72 2,470 92 215 7 73 455 67 41 o 0 354 504 o 0 1 16 351 83 2 412 o 0 354 503 o 0 2 5 351 496 1 3 83 50 261 418 10 35 33 39 295 454 26 12 5 0 256 193 93 312 12 5 329 488 13 11 o 0 352 504 2 0 5 6 348 496 1 2 10 14 340 485 4 6 252 102 81 2 428 o 2 426 o 2 428 o 13 416 1 81 327 22 46 354 30 4 285 141 10 407 12 o 430 o 10 420 o 11 417 o 783 74 83 o 936 o 5 930 o o 659 o 4 651 5 70 563 33 68 530 80 6 584 346 9 846 81 o 656 4 3 654 4 15 845 76 328 61 21 o 406 4 15 393 3 1 409 o 3 408 o 9 401 o 42 365 4 2 271 138 8 388 15 o 410 o o 410 o 22 383 6 Commercial Supply Commercial Fishing Sport Fishing Main No Yes Main No Yes Main No Yes Main No Yes Main No Yes Main No Yes Transportation Main No Yes Main No Yes Sight Seeing Main No Yes Main No Yes Susitna Study Main No Yes Other Activity Main No Yes Private Supply ~, - - ---------,-------------------------------------------------.., ~he numb,ers presented are estimates. bRespondents indicated whether an activity was the main activity (Main),a secondary activity engaged in (Yes), or an activity they did not participate in (No). Howe (1985) 61 62 Howe (1985) Table 7.5 Percent of boats by activity and month for boats exiting at the Talkeetna boat launch ora!!::!!!!2.!._.!2~~~_ aThe numbers presented are estimates. bRespondents indicated whether an activity was the main activity (Main),a secondary activity engaged in (Yes),or an activity they did not participate in (No). 39 53 8 o 100 O· o 95 5 o 100 a o 100 o 4 95 2 15 76 9 o 100 o 7 81 12 o 100 o 14 86 1 o 98 2 30 69 2 o 100 a a 69 31 o 100 a o 100 o 2 95 3 14 86 o a 100 o 17 78 5 o 100 o 10 90 a o 100 o 72 28 1 o 100 o 1 99 o o 100 o o 100 o o 98 2 13 86 1 o 100 o 1 79 21 o 99 1 14 86 o o 100 o 17 66 16 o 100 o a 100 a a 100 a a 100 o 7 93 1 16 65 19 1 99 o 8 84 8 o 100 a 15 84 2 o 96 4 . bResponse· Category July Aug Sept Overall Commercial Supply Activity Comme1:'cial Fishing Camping Mining Hunting Sport Fishing Main No Yes Main No Yes Main No Yes Main No Yes Main No Yes Main No Yes Transport,ation Main No Yes Main No Yes Sight Seeing Main No Yes Main No Yes Susitna Study Main No Yes Other Activity Main No Yes Trapping Private Supply 1- I~ I~ If J- I! j j I l~ -I; -. I -I ""'"I !""'" I ~ I J' ~ ti~ t 63 Howe (1985) Table 7.6 Number of boats by activity and month for boats exiting at the Talkeetna boat launch or airstrip.1984.a b Respondtmts indicated whether an activity was the main activity (Main).a secondary activity engaged in (Yes),or an activity they did not participate in (No). 19 156 44 209 1 33 o 0 64 399 o 0 o 1 44 377 20 20 o 0 64 399 o 0 o 0 64 399 o 0 1 14 60 377 2 6 9 59 54 301 o 37 o 1 64 397 o 0 11 27 50 324 3 48 o 0 64 397 o 1 6 54 57 340 o 3 o 0 61 388 o 8 104 40 1 o 146 o 1 144 o o 146 o o 146 o o 143 3 19 125 1 o 146 o 1 115 30 o 144 1 20 126 o o 146 o 33 125 31 o 189 o o 189 o o 189 o o 189 o 13 174 1 31 122 36 1 187 o 15 159 15 o 189 o 28 157 3 o 181 8 bResponse Category July Aug Sept Overall Commercia.l Supply a The numbers presented are estimates. Camping Mining Commercia.! Fishin.g Activity Sport Fishing Main No Yes Main No Yes Main No Yes Main No Yes Main No Yes Main No Yes Transportation Main No Yes Main No Yes Sight Seeing Main No Yes Main No Yes Susitna Study Main No Yes Other Activity Main No Yes Hunting Trapping Private Supply , ,- f I: 1- 1~ I~ 1 j~ j~ jF- jr j r.·., .I .",- jt tr ~ jl 'it I~ jf ,~ I f \-; r-'tl .................MIll .......~.......~~lIIiIIIiIiI ~~..'~~c"'J r"'~l "~T""J "T"')~~'~)c""l '~'J •....,}'~J "-1 "~')1 "')"J --1 ] .8,hTable7.7 Number of people for residence groups by exit location,1984. Residence Groups IiIiIiliIiII lilIIii8l 1 Interview Location Month 1 2 3 4 5 7 8 9 10 11 12 99 Susitna Landing Talkeetna May Jun Jul Aug Sep Overall Jul Aug Sep Overall 149 261 226 560 157 370 116 311 146 388 794 1,890 2 35 7 37 5 42 14 114 3 8 5 1 o 17 o o o o 2 8 7 6 8 31 10 8 6 24 o 1 1 o o 2 1 2 o 3 o 1 o o o 1 o o o o o o o o 1 1 o o o o 15 6 3 8 o 32 1 o 2 3 o o o 2 3 5 o o 2 2 16 26 14 14 5 75 5 4 1 10 o 1 o 1 o 2 o o o o 12 5 3 3 4 27 3 o 2 5 ()l It>Willow Creek Jul Aug Sep Overall 74 220 48 231 23 150 145 601 o 2 1 3 7 4 o 11 o o o o o o o o o o o o 3 o 1 4 o 45 o 22 o 3 o 70 o o o o o 9 2 11 a The numbers presented are sample values. b Groups 1 Montana Creek to Palmer/Wasilla 3 Seward,Cooper Landing to Homer 5 Cantwell to Nenana 7 Delta Junction,Tok,Valdez,Kodiak 9 Fairbanks 11 USA,non-Alaska Howe (1985) 2 Chugiak to Girdwood 4 Peter's Creek,Talkeetna.Trapper Creek 6 Glennallen and Paxson B Juneau,Ketchikan 10 Missing 12 Non-USA 99 Others _. I~ 1-aTable7.8:Number of anticipated visits by exit location,1984. Under 2 2-5 6-10 11-20 Over 20 Exit Location Month People %People %People %People %People % Susitna Landing May 69 Jun 117 Jul 31 Aug 51 Sep 58 Overall 326 16 66 14 218 6 88 11 105 11 104 12 581 18 36 19 30 23 27 48 190 130 71 109 548 11 148 23 297 24 299 16 229 20 278 20 1,251 35 36 55 50 51 46 93 22 a a a a a a a a a a Talkeetna,Jul Aug Sep Overall 11 22 23 43 17 31 51 32 1 10 24 35 2 23 80 29 5 2 2 9 10 4 4 6 32 19 11 62 65 35 20 39 a 0 a a a 0 o 0 Howe (1985) a l'The numbers presented are samp e values.Boaters were asked to estimate the number of visits during 1984. j Jr Ji I It if ~r.,".t Willow Creek Jul 17 Aug 26 Sep 10 Overall 53 6 31 8 62 6 24 7 117 12 25 16 15 55 58 15 128 19 19 9 16 56 78 35 169 19 134 46 25 85 28 20 90 52 22 309 40 II Ir Ir 65 -,':'-'-'-~, 1 ~-j t ))1 _..j 1 'J )}1 }))J 1 aTable8.1 Boats with navigational problems by exit location,1984. ------------------------------------------------------------------------------------------ Debris Bars Rocks Velocity -------------------------------------------------------------- Boats %Boats %Boats %Boats % Exit Month/Total With With Total With With Total With With Total With With Location Season Boats Prob Prob Boats Prob Prob Boats Prob Prob Boats Prob Prob ------------------------------------------------------------------------------------------ Susitna May 406 63 16 406 17 4 407 8 2 407 47 12 Jun 898 149 17 898 83 9 898 103 11 890 16 2 Jul 427 16 4 429 40 9 427 19 4 427 3 1 Aug 352 19 5 348 44 13 348 11 3 347 0 0 Sep 499 12 2 502 96 19 500 54 11 496 4 1 Overall 2,582 259 10 2,583 280 11 2,580 195 8 2,567 70 3 Kings 1,400 214 15 1,401 105 7 1,401 114 8 1,393 63 5 Other fish 1,181 44 4 1.181 114 15 1,178 80 7 1,172 6 1 0"1 Talkeetna Jul 188 1 1 188 13 7 189 27 14 188 13 7 0"1 Aug 146 0 0 146 0 0 146 0 0 146 0 0 Sep 64 1 2 64 2 3 64 2 3 64 1 2 Overall 398 2 1 398 15 4 399 29 7 398 14 4 Other fish 397 2 1 397 15 4 398 29 7 397 14 4 Willow Jul 224 4 2 223 7 3 223 6 3 224 1 1 Aug 224 28 12 222 63 28 219 51 23 217 0 0 Sep 122 7 6 122 20 16 124 17 14 122 2 2 Overall 570 39 7 567 90 16 566 74 13 563 3 1 Other fish 555 39 7 552 89 16 551 72 13 548 3 1 ---------------------------------------------------------~--------------------------------a Since a single boat may have had several differentThenumberspresented~re estimates. navigational problems during a tript the sum of boats with problems over all problem groups may not represent the number of unique boats with problems. Howe (1985) R21/10 76 TABLE 9.1 FLOW CONSTRAINTS FOR ENVIRONMENTAL FLOW REQUIREMENT CASE EVI ~ Water Gold Creek Flow (ds)Water Gold Creek Flow (cfs) Week Minimum Maximum Week Minimum Maximum 14 2,000 16,000 40 9,000*35,000-15 2 J OOO 16,000 41 9,000*35,000 16 2,000 16,000 42 9,000*35,000 17 2,000 16 J OOO 43 9.000*35,000 18 2,000 16,000 44 9,000*35,000 19 2,000 16,000 45 9,000*35,000 20 2,000 16,000 46 9,000*35,000 ..-21 2,000 16,000 47 9,000*35,000 22 2,000 16,000 48 9,000*35,000 23 2,000 16,000 49 8,000 35,000 24 2,000 16,000 50 7,000 35,000 25 2,000 16,000 51 6,000 35,000 26 2,000 16,000 52 6,000 35,000 27 2,000 16,000 1 6,000 18,000..-28 2,000 16,000 2 6,000 17,000 29 2,000 16,000 3 5,000 16,000 30 2,000 16,000 4 4,000 16,000 31 2,000 16,000 5 3,000 16,000 32 4,000 16,000 6 3 J OOO 16,000 33 6,000 16,000 7 3,000 16,000 34 6,000 16,000 8 3,000 16,000.- 35 6,000 16,000 9 3,000 16,000 36 9,000*35,000 10 2,000 16,000 37 9,000*35,000 11 2,000 16,000-38 9,000*35,000 12 2,000 16,000 39 9,000*35,000 13 2,000 16,000 ~*Minimum summer flows are 9,000 cfs except 1.0 dry years when the minimum will be 8,000 cfs.A dry year is defined by the one-in-ten year low flo\l,.-(1985)H~E - 67 .-, R21/10a )J J )I 1 J )1 J »))1 .~ TABLE 9.2 FLOW DURATION DATA AT GOLD CREEK FOR NATURAL,WATANA ONLY, AND WATANAjDEVIL CANYON,OPEN-WATER SEASON Week 32 (May 6 -May 12)Week 33 (May 13 -May 19)Week 34 (May 20 -May 26) Natura I 1996 2020 Natura I 1996 .2020 Natura I 1996 2020 Pe rcent Conditions Load Load Conditions Load Load Conditions Load Load 0 20,400 12,100 12,500 22,000 12,700 12,700 33,900 15,200 14,500 25 11,500 8,220 9,250 18,400 9,580 10,300 23,000 11,800 11,400 50 6,330 7,070 7,650 13,900 8,620 9,080 18,600 10,500 10,100 75 4,340 6,600 6,740 10,800 7,970 7,930 13,500 8,640 8,160 90 2,190 5,760 5,850 4,120 6,830 6,570 6,920 7,310 6,640 100 1,040 4,630 4,680 1,400 5,990 5,990 3,100 6,600 6,160 Week 35 (May 27 -June 2)Week 36 (June 3 -June 9)Week 37 (June 10 -June 16) Natural 1996 2020 Natural 1996 2020 Natura I 1996 2020 Percent Conditions Load Load Conditions Load Load Conditions Load Load 0 44,300 19,500 16,900 75,100 17,100 14,700 58,800 16,800 13,800 25 29,600 13,000 11,800 30,300 12,700 11,100 34,800 13,200 11,600 50 22,100 12,100 10,900 25,900 11,400 10,300 27,200 11,800 10,300 Q)75 18,500 9,840 9,850 19,800 9,930 8,950 20,600 9,920 9,260 co 90 14,400 8,320 7,410 16,000 8,730 8,550 16,600 8,950 8,510 100 8,700 7,440 6,600 12,800 8,340 7,990 14,900 8,160 7,990 Week 38 (June 17 -June 23)Week 39 (June 24 -June 30)Week 40 (July 1 -July 7) Natural 1996 2020 Natural 1996 2020 Natura I 1996 2020 Pe rcent Conditions Load Load Conditions Load Load Condjtions Load Load 0 50,300 15,600 13,800 39,600 14,000 12,600 34,200 12,100 11,000 25 35,800 12,900 11,500 30,200 12,200 10,900 27,200 10,800 9,720 50 27,000 11,800 10,300 26,000 11,500 10,400 23,400 9,990 9,130 75 21,200 9,570 8,810 22,000 9,570 8,830 20,600 9,080 9,050 90 16,000 8,640 8,260 17,500 8,560 8,320 18,700 8,920 9,000 100 13,500 7,990 7,990 16,200 7,990 7,990 13,900 7,990 7,990 1 1 R21/10a 2 ,J 1 ~)}J a J 1 )))} TABLE 9.2 FlOW DURATION DATA AT GOLD CREEK FOR NATURAL,WATANA ONLY, AND WATANAjDEVIL CANYON,OPEN-WATER SEASON (Continued) Week 41 (july 8 -July 14)Week 42 (July 15 -July 21)week 42 (July 22 -July 28) Natura I 1996 2020 Natura I 1996 2020 Natura I 1996 2020 pe rcent Conditions Load Load Conditions Load Load Conditions Load Load 0 42,100 14,800 12,100 41,200 14,500 13,300 36,700 13,500 12,600 25 26,800 11,000 9,710 27,800 10,900 9,880 27,000 10,700 9,400 50 23,200 9.870 9,020 24,000 9,590 9,020 22,000 9,750 8,950 75 20,600 8,990 8,500 20,300 8,960 8,800 19,600 8,850 8,600 90 18,200 8,300 8,190 17,700 8,260 8,670 17,500 8,250 8,400 100 17,000 7,990 7,990 15,200 7,990 7,990 15,100 7,990 7,990 Week 44 (July 29 -August 4)Week 45 (August 5 -August 11)Week 42 (July 22 -July 28) Natura I 1996 2020 Natural 1996 2020 Natural 1996 2020 Pe rcent Conditions Load Load Conditions Load Load Conditions Load Load 0 38,700 26,100 12,300 44,800 23,000 11,800 54,900 41,500 26,000 25 28,100 11,900 10,000 25,400 11 ,100 9,870 23,400 11,100 9,990 50 24,400 10,300 9,120 22,400 10,200 9,080 20,400 9,860 9,090 0"1 75 21,700 9,090 8,580 19,900 9,030 8,710 18,612 9,090 8,720w9019,100 8,620 8,260 18,300 8,480 8,510 15,700 8,740 8,520 100 13,400 7,990 7,990 14,300 7,990 7,990 7,390 7,990 7,990 Week 47 (August 19 -August 25)Week 48 (August 20 -September 1)Week 49 (September 2 -September 8) Natural 1996 2020 Natural 1996 2020 Natura I 1996 2020 Pe rcent Conditions Load Load Conditions Load Load Conditions Load Load 0 44,200 37,100 37,100 43,200 25,000 25,000 30,100 29,100 29,100 25 22,500 10,800 10,100 22,400 13,500 10,100 18,800 13,500 13,300 50 19,900 9,790 9,320 17,000 10,200 9,360 14,300 10,900 9,970 75 16,300 9,090 8,920 13,500 9,040 8,740 11,500 8,810 8,410 90 14,100 8,690 8,680 9,620 8,520 8,500 8,900 8,260 8,160 100 6,000 7,990 7,990 5,590 7,990 7,990 6,300 7,990 7,990 ] R21/10a 3 1 J -})1 "1 1 j .~ J -1 .J, j "-lo TABLE 9.2 FLOW DURATION DATA AT GOLD CREEK FOR NATURAL,WATANA ONLY, AND WATANA/DEVIL CANYON,OPEN-WATER SEASON (Continued) Week 50 (September 9 -September 15)Week 51 (September 16 -22)Week 52 (September 23 -30) Natura I 1996 2020 Natura I 1996 2020 Natural 1996 2020 Pe rcent Conditions Load Load Conditions Load Load Conditions Load Load 0 29,000 24,500 24,500 26,600 21.900 21,900 25,100 21.900 19,800 25 16,800 14,500 14,100 15,100 12,400 12,000 15,000 11,400 10,400 50 14,000 11,000 10,300 12.200 10,800 10,200 11,500 9,420 9,550 75 10,000 9,080 7,360 8,960 8,730 8,020 7,660 8,620 8,360 90 8,630 7,360 7,140 6,920 7,010 6,230 6,180 6,610 6,250 100 5,510 6,990 6,990 4,720 5,990 5,990 4,530 5,990 5,990 ]I R21!lOa 4 ]»J 'J ,1 -])])» TABLE 9.3 FLOW DURATION DATA AT SUNSHINE FOR NATURAL,WATANA ONLY, AND WATANA!DEVIL CANYON,OPEN-WATER SEASON Week 32 (May 6 -May 12)Week 33 (May 13 -May 19)Week 34 (May 20 -May 26) Natura I 1996 2020 Natura I 1996 2020 Natura I 1996 2020 Percent Conditions Load Load Conditions Load Load Conditions Load Load 0 40,800 31,800 33,100 45,500 43,800 44,600 71,200 54,800 54,500 25 21,400 18,900 19,000 33,000 26,300 27,000 46,700 32,500 30,700 50 13,000 14,200 15,400 29,300 22,600 22,500 36,100 28,000 27,900 75 9,460 11,200 11,300 20,900 17,300 17,400 29,900 25,400 25,000 90 6,330 10,000 10,100 10,200 14,100 13,900 17,300 17,500 17,800 100 3,930 9,010 9,070 5,260 11,100 9,860 10,800 16,100 14,100 Week 35 (May 27 -June 2)Week 36 (June 3 -June 9)week 37 (June 10 -June 16) Natura I 1996 2020 Natura I 1996 2020 Natura I 1996 2020 Percent Conditions Load Load Conditions Load Load Conditions Load Load 0 77,800 53,000 50,500 160,000 99,800 96,300 121,000 82,400 79,800 25 61,100 45,500 43,700 68,000 49,500 48,200 76,400 56,900 54,700 -..J 50 48,800 38,200 37 ,400 54,500 38,700 37,000 61,500 47,200 45,700 I-'75 38,100 30,200 29,100 45,700 35,200 32,200 51,500 39,100 38,600 90 29,200 24,800 23,000 37,500 30,600 29,900 41,000 33,300 32,500 100 23,900 20,700 20,600 28,300 23,800 23,500 37,500 31,200 29,600 Week 38 (June 17 -June 23)Week 39 (June 24 -June 30)Week 40 (JUly 1 -July 7) Natura I 1996 2020 Natura I 1996 2020 Natura I 1996 2020 Pe rcent Conditions Load Load Conditions Load Load Conditions Load Load 0 109,000 77,600 75,500 106,000 77,600 76,200 79,200 57,900 56,700 25 74,100 52,800 51,000 71,100 52,900 51,900 66,000 50,200 49,100 50 63,600 46,400 45,600 63,800 49,200 48,200 60,900 46,500 45,800 75 52,100 40,400 39,800 57,300 44,100 44,000 55,900 44,400 43,200 90 43,100 35,600 35,100 49,200 40,400 39,900 50,200 40,600 40,600 100 39,300 34,600 34,200 46,700 39,200 38,800 45,400 37,500 36,600 J R21/101 5 1 B )1 ]J 1 s ))i J 1 J TABLE 9.3 FLOW DURATION DATA AT SUNSHINE FOR NATURAL,WATANA ONLY, AND WATANA/DEVIL CANYON,OPEN-WATER SEASON (Continued) Week 41 (july 8 -July 14)Week 42 (July 15 -July 21)week 43 (july 22 -July 28) Natura I 1996 2020 Natural 1996 2020 Natura I 1996 2020 percent Conditions Load Load Conditions Load Load Conditions Load Load 0 116,000 88,500 85,600 97,300 78,400 77,100 90,600 68,600 67,100 25 72,900 55,500 54,200 73,800 56,200 55,100 71,600 55,200 53,800 50 60,900 49,000 49,100 64,400 49,600 49,800 62,900 49,400 49,200 75 56,100 44,200 43,200 57,700 45,400 44,600 53,800 44,000 42,400 90 52,300 42,000 41,300 48,600 39,100 39,100 48,800 38,700 38,500 100 45,800 37,800 37,800 42,000 35,800 35,800 41,000 33,800 33,800 Week 44 (july 29 -August 4)Week 45 (August 5 -August 11)Week 46 (August 12 -August 18) Natura I 1996 2020 Natura I 1996 2020 Natural 1996 2020 Pe rcent Conditions Load Load Conditions Load Load Conditions Load Load 0 94,300 73,000 75,600 111,000 78,500 75,600 134,000 121,000 96,000 25 73,000 56,400 51,700 65,700 53,900 51,700 63,600 52,200 52,600 -..J 50 61,400 47,700 48,200 59,300 46,800 45,700 52,900 44,800 43,900 l\.l 75 58,200 44,200 44,100 53,200 43,000 42,500 47,100.38,700 38,500 90 50,400 40,700 39,600 49,700 37,900 37,600 42,000 35,100 34,100 100 38,200 32,800 32,800 38,700 32,500 32,500 20,100 20,700 20,700 Week 47 (August 19 -August 25)Week 48 (August 26 -September 1)Week 49 (September 2 -September 8) Natura I 1996 2020 Natural 1996 2020 Natura I 1996 2020 Pe rcen.t.Conditions Load Load Conditions Load .Load Conditions Load Load 0 111,000 84,000 82,900 87,700 63,100 61,000 60,100 60,100 60,100 25 58,900 49,000 48,600 52,100 41,500 40,000 45,600 40,800 39,000 50 51,100 43,200 42,000 43,200 35,900 35,800 35,800 33,000 32,500 75 43,500 36,100 35,900 35,900 32,600 31,900 31,500 28,800 28,300 90 38,400 31,300 29,200 30,100 28,700 28,300 25,500 23,800 22,700 100 16,400 18,300 18,300 16,300 18,700 18,700 18,100 19,800 19,800 -1 R21j101 6 1 ,J J 1 1 j 1 1 --S j J J ) -.Jw TABLE 9.3 FLOW DURATION DATA AT SUNSHINE FOR NATURAL,WATANA ONLY, AND WATANAjDEVIL CANYON,OPEN-WATER SEASON (Continued) Week 50 (September 9 -September 15)Week 51 (September 16 -22)Week 52 (September 23 -30) Natura I 1996 2020 Natura I 1996 2020 Natura I 1996 2020 Pe rcent Conditions Load Load Conditions Load Load Conditions Load Load 0 56,600 52,400 52,400 76,200 60,800 58,000 79,100 69,200 67,100 25 42,600 39,500 36,400 35,200 33,700 31,800 35,800 31,300 27,800 50 33,900 31,400 30,900 29,100 27,300 26,700 26,700 23,800 23,700 75 27,600 25,900 25,800 23,100 22,600 22,300 23,000 21,000 19,700 90 22,400 .22,000 21,900 19,200 19,500 18,200 15,800 15,000 15,300 100 15,400 16,900 16,900 13,000 14,200 14,200 12,500 12,100 11,800 I 11 R21j10a 7 1 1 J J J )1 1 ---J )J )J 1 j TABLE 9.4 FLOW DURATION DATA AT SUSITNA STATION FOR NATURAL,WATANA ONLY, AND WATANAjDEVIL CANYON,OPEN-WATER SEASON Week 32 (May 6 -May 12)Week 33 (May 13 -May 19)Week 34 (May 20 -May 26) Natura I 1996 2020 Natura I 1996 2020 Natura I 1996 2020 Pe rcent Conditions Load Load Conditions Load Load Conditions Load Load 0 98,200 94,600 94,700 93,000 ·86,900 85,600 98,600 86,500 84,600 25 61,900 58,600 60,100 73,400 62,300 65,900 81,700 70,000 69,800 50 42,600 32,500 34,400 59,000 55,000 55,400 73,500 62,600 62,500 75 19,100 21,400 21,800 52,100 45,600 46,400 63,500 56,500 54,900 90 14,800 16,200 15,700 34,700 37,500 36,200 51,900 51,700 52,800 100 10,200 11,100 12,400 30,100 24,700 26,000 44,500 33,600 34,300 Week 35 (May 27 -June 2)Week 36 (June 3 -June 9)Week 37 (June 10 -June 16) Natura I 1996 2020 Natura I 1996 2020 Natura I 1996 2020 Pe rcent Conditions Load Load Conditions Load Load Conditions Load Load 0 129,000 116,000 113,000 158,000 135,000 133,000 173,000 149,000 147,000 25 108,000 94,300 87,900 117,000 105,000 104,000 118,000 102,000 101,000 50 85,700 74,400 74,000 104,000 88,400 89,600 108,000 86,300 85,200 -..J 75 69,000 59,900 59,200 91,400 76,600 74,500 87,900 73,200 72,700 .p.90 59,400 52,200 49,600 75,200 60,700 62,700 72,200 64,000 61,700 100 46,000 29,700 28,400 63,900 49,500 47,400 63,400 42,800 40,600 Week 38 (June 17 -June 23)Week 39 (June 24 -June 30)Week 40 (July 1 -July 7) Natura I 1996 2020 Natura I 1996 2020 Natura I 1996 2020 Percent Conditions Load Load Conditions Load Load Conditions Load Load 0 172,000 147,000 146,000 182,000 154,000 153,000 162,000 146,000 146,000 25 129,000 108,000 106,000 134,000 116,000 117,000 134,000 120,000 119,000 50 112,000 95,200 94,900 123,000 108,000 109,000 119,000 106,000 105,000 75 101,000 89,000 87,700 114,000 103,000 102,000 106,000 93,700 92,500 90 84,200 71,700 71,500 104,000 91,500 91,300 98,600 90,300 88,400 100 75,900 61,600 60,300 96,300 79,600 78,500 92,600 82,300 81,500 J~)~J J 1 1 ]1 1 J J -}.~~J J ] R21j10a 8 TABLE 9.4 FLOW DURATION DATA AT SUSITNA STATION FOR NATURAL,WATANA ONLY, AND WATANAjDEVIL CANYON,OPEN-WATER SEASON (Continued) Week 41 (July 8 -July 14)Week 42 (july 15 -July 21)Week 43 (july 22 -July 28) Natura I 1996 2020 Natura I 1996 2020 Natura I 1996 2020 Pe reent Conditions Load Load Conditions Load Load Conditions Load Load 0 190,000 169,000 168,000 191,000 169,000 168,000 181,000 163,000 163,000 25 150,000 130,800 130,000 110,000 130,000 129,000 144,000 123,000 124,000 50 124,000 111,184 113,000 126,000 111,000 112,000 119,000 103,000 103,000 75 112,000 99,700 98,900 117,000 100,000 102,000 104,000 92,400 92,200 90 104,000 90,800 90,600 96,000 83,700 82,100 93,300 83,800 82,300 100 91,100 79,200 79,100 86,900 79,500 79,500 84,700 76,500 74,900 Week 44 (july 29 -August 4)Week 45 (August 5 -August 11)Week 46 (August 12 -August 18) Natura I 1996 2020 Natura I 1996 2020 Natura I 1996 2020 Pe reem Conditions Load Load Conditions Load Load Conditions Load Load 0 199,000 179,000 176,000 177,000 162,000 160,000 207,000 178,000 183,000 25 134,000 120,000 119,000 136,000 121,000 121,000 131,000 117,000 "7,000 -..J 50 122,000 104,000 104,000 120,000 109,000 107,000 111,000 96,700 97,600 l/1 75 109,000 96,000 94,400 109,000 97,500 97,300 100,000 90,700 90,100 90 99,700 85,200 85,100 101,000 90,500 89,500 82,200 78,700 77,700 100 91,000 82,300 82,300 96,800 87,100 87,100 75,300 66,200 64,900 Week 47 (August"19 -August 25)Week 48 (August 26 -September 1)Week 49 (September 2 -September 8) Natura I 1996 2020 Natura I 1996 2020 Natura I 1996 2020 Pe reent Conditions Load Load Conditions Load Load Conditions Load Load 0 135,000 134,000 134,000 116,000 116,000 116,000 101,000 97,600 97,600 25 110,000 106,000 106,000 "91,300 84,900 84,700 78,400 77,000 76,400 50 100,000 89,200 88,400 84,600 72,800 72,500 69,900 65,200 64,500 75 89,400 77,900 77,900 70,400 "66,600 65,200 59,600 56,000 53,600 90 80,900 75,100 75,100 65,900 60,800 58,400 46,800 46,800 44,200 100 55,300 57,300 57,300 53,600 56,000 55,800 42,300 42,600 42,600 -..l (j\ J J -1 1 1 J I J .-)j R21/10a 9 J J TABLE 9.4 FLOW DURATION DATA AT SUSITNA STATION FOR NATURAL,WATANA ONLY, AND WATANA/DEVIL CANYON,OPEN-WATER SEASON (Cont i nued ) Week 50 (September 9 -September 15)Week 51 (September 16 -22)Week 52 (September 23 -30) Natura I 1996 2020 Natura I 1996 2020 Natura I 1996 2020 Pe rcent Conditions Load Load Conditions Load Load Conditions Load Load 0 102,000 97,700 95,700 175,000 159,000 156,000 116,000 103,000 101,000 25 84,100 77,800 80,400 89,500 84,400 81,900 91,900 78,900 80,100 50 67,500 65,100 63,900 64,800 62,700 61,000 61,900 53,800 51,500 75 55,300 51,100 50,800 51,000 51,300 50,300 46,000 38,600 39,900 90 40,000 40,800 40,800 39,200 39,000 38,000 36,600 34,800 32,600 100 38,300 38,300 38,300 34,700 35,600 35,600 28,400 24,900 24,900 ,. - - - -! FIGURES RIVE ILE 103.2 SINGLE CHANNEL: -STABLE -NON-ERODIBLE BANKS;CONTROLLED BY VALLEY WALLS,BEDROCK OR RMOR LAYER CONSISTING OF GRAVEL /COBBLES. -CHANNEL MAY BE EITHER STRAIGHT OR MEANDERING.IN STRAIGHT CHANNELS, THALWEG OFTEN MEANDERS ACROSS CHANNEL .. -OCCASIONAL FRAGMENTARY ALLUVIAL DEPOSITS IN FLOODPLAIN. Single-Channel River Pattern Source:R&M (1982A) PREPARED BY; ~'~~~l-------- ~&M CONSULTANTS.INC.Figure 3.1 PREPARED FOR; [X]£OO~£0 ~[ID&~©@ SUSI TNA JOINT VENTURE RIVER MI LE 124.4 SPLIT CHANNEL: -M IN CHANNEL BEHAVES SIMILAR TO SINGLE CHANNEL AT LOW FLOW. -SIDE CHANNELS PROVIDE FLOOD RELIEF AT HIGH FLOWS (GREATER THAN 20,000 CFS). -ISLANDS WELL ESTABLISHED WITH VEGETATION. -GRAVEL/COBBLE BED MATERIAL. -EAN ANNUAL FLOOD CORRELATES WITH BANKFULL FLOW. - C NNELS ARE MODERATELY STABLE. Split-Channel River Pattern Source:R&M (1982A) PREPAREO--=-Il_Y"_ ~~i\v ~&M CONSULTANTS.INC.Figure 3.2 79 PREPARED FOR: 'USI TNA JOINT VENTl,Rc CHULITNA RIVER NEAR CONFLUENCE WITH SUSITNA RIVER BRAIDED CHANNEL: -FLOOOPlAlN IS VERY WIDE AND SHALLOW EVEN AT FLOOD FLOW. -MULTIPLE AND INTERLACING CHANNELS IN UNVEGETATED GRAVEL FLOODPLAIN -MOVE LARGE QUANTITIES OF BED MATERIAL DURING FLOWS GREATER THAN BANKFULL -RESULTS FROM COMBINATION OF HIGH RATES OF BEDLOAD TRANSPORT,LOW CHANNEL STABILITY,HIGH SEDIMENT SUPPLY I HIGH GRADIENTS AND LOW UPSTREAM FLOW REGULATION. Braided-Channel River Pattern Source:R&M (1982A) PREPARE D BY. ~R\I,r--------- Fl&M CONSULTANTS,INC. Figure 3.3 PREPARED FOR; [X]&~~&c ~[ID&@©@ SUSITNA JOINT VENTURE E TA ISLANDS MULTI-CHANNEL (DELTA ISLANDS): -VERY BROAD FLOODPLAIN WITH LITILE LATERAL CONTROL. -MULTIPLE CHANNELS CONSIST OF A MIX OF BRAIOti>,SIlt'T CHANNEL AND SINGLE CHANNELS WITHIN 'FLOODPLAIN. -RELATIVELY UNSTABLE,SUBJECT TO MAJOR LOCAL CHANGES DURING SINGLE FLOOD EVENTS. -LARGE AMOUNT OF FlNE SUSPENDED SEDIMENT HELPS STABILIZE 8ANI(S~ DENSE VEGETATION EFFECTIVE IN TRAPPING SEDIMENT. -BED MATERIAL CONSISTS OF GRAVEL/SAND WITH POCKETS OF SILT. Multi-Channel River Pattern Source:R&M (1982A) PREPARED BY; ==-~'c./71-------- Fl&M CONSULTANTS,INC• ....O'N.....01ll0"OQI."'......__••••"'••""",ve.a•• Figure 3.4 81 PREPARED FOR; Figure 3.5 split channelmorpholo~1 below west fork Susitna confluence. figure 3.6 Vee C~~yon. ?RE?"'RED BY. ;2~~T-------- &M CONSULTANTS.INC. Figures 3.5 and 3.6 82 SL:SITNA JOINT VUHLJ"E Figure 3.7 Susitna River near Watana Darnsite. Figure 3.8 Rapids at Devil Canyon. SLSITNA JOINT VENTURE Figures 3.7 and 3.8~&M CONSULTANTS,INC . ....0_••••<3<.-'00'•••.....,~__...•....v ••_. I"REPl\ED BY.~'~_________PREPARED FOR; 83 OJ •+:- Figure 3.9 Single channel morphology,Susi tna River,RM 150 to RM 144. Flow at Gold Creek ==18,000 cfs.August 24,1980 . Figure 3.10 10 Spli t-c:hanne 1 morphology,Sus i tna Ri ve r,RH 144 to RN 137 o cfs.AUGust 24.1980 Scale 1"""4000' PREPARED BY; ~~-=-=-=---------== R&M CONSULTANTS,INC. .,..01.....OA8 a.OLCOl."'"HVDPlOLOaUI-Ta .U!Q'~.-YDRO Figures 3.9 and 3.10 PRE PARED FOR; [j[J&~~&0 ~[ID&~©@ SUSITNA JOINT VENTURE m U1 Figure 3.11 Split-channel morphology,Susitna RLver,RM 137 to RM 131. Flow at Gold Creek =18,000 efs.August 24,1980 Figure 3.12 Side channels and sloughs along Susitna River,RM 126 to RM 119. low at Gold Creek =18,000 efs.August 24,1980 Seale I"=4000' PREPARED BY: ~.-=:...-_-----= R&M CONSULTANTS,INC. .NG1N••~.O.OL.COIU-Til HVDROI.OamTa Figures 3.11 and 3.12 PREPARED FOR: G{]&OO~&0 @[ID&®©@ SUSITNA JOINT \/ftHURE (J:) (J) Single channel morphology,Susitna River,RM 110 t.o RM 104. Flow at Gold Creed =18,000 cfs.August 24,1980. PREPARED BY: ~~-=-=-=----=----'----= R&M CONSULTANTS!INC. .NGINeItRIt aIDLOtiIST.HVOAOLDQIQTa .UA~.VDRIJ Figure 3.13 PRE PARED FOR; [M]&~~&D~®&§©@ SUSITNA ~OINT VENTURE Confluence of Susitna,Chulitna,and Talkeetna Rivers,RM 102 to ID195. Flow at Sunshine approximately 39,400 cfs.August 29,1980 Scale 1"=4000 I F'REPAREO;:,.....::8~Y_:_ ...,g~ R&M CONSULT NTS,INC.Figure 3.14 87 F'REPAREO FOR: SUSITNA JOINT VENTURE Braided river morphology downstream of Talkeetna RM 72 to RM 65. Flow at Sunshine approximately 39,400 cfs.August 24,1980 Scale 1"==4000 I PREPAREO BY: .....s.~,71--------- Fl&M CCNBUL.TANTS,INC.Figure 3.15 88 PREPARED FOR: SUSITNA JOINT VENTURE Delta Islands,RM 50 to RM 43. Flow at Sunshine approximately 39,400 cfs.August 24,1980 Scale 1"=4000' PREPAREO BY.~':""--------- ~&M CONSULTANTS,INC. Figure 3.16 PREPAREO FOR; [}{]&OO~&c ~[ID£~©@ SUSITNA JOINT VENTURE Deshka River Confluence Flow at Sunshine approximately 39,400 cfs. ,.,.~,:','/r...~."~".I,(...~\'.,'J•. •4.I '1a~'"I. August 24,1980 Scale 1"=4000' PREPARED BY:--6~~~--------- R&M CONSULTANTS,INC._____...,,__....,.v...._ Figure 3.17 90 PREPARED FOR: [):{]&OO~&QmOO&®©@ SUSITNA JOINT VENTURE Yentna River Confluence Flow at Sunshine approximately 39,400 cfs.August 24,1980 Scale 1"=4000' PREPARED BY: ~-;----------- R&M CONSULTANTS,INC. Figure 3.18 91 PREPARED FOR: SUSITNA JOINT VENTURE -- 101 101 10 1 101 10 1 1 1 1 1 -1 1 1 I~.._.1 I·~ 4 4 4 4 4 ~'~;;::-;f-+-++-+-j--'-j-+--1 I I I I I P-,JI'-.---i......P-\........c-4-I--1--+-+--+-l..............~104 104 104 10 4 ~~~t'--~.~!!r......~~~~!~-I _I -I -I -ISIS'S'SI SI i:~~~--I :i:--j:-i : .~.'."~10'1'-,...~-r-.10'1'-.~-II 10'1'-,r-.r-.r-II 10 1 'I--I---I--II 10'~~~~~~~.r-..~~§\~~\1 •1 1 1 1 _.1 •1 4 '....4 f-.4 4 •4 1- --+--1---f--t-+-'-P"'t-;;;::I-f--I '.,..•.........-I-~HI-j-f-f-+--+--+-+:..-t\ I •Z ..I .-;;;;;;I •Z I J.....U11I'Y "',f1 NUAI!Y'r-..I-....IuJ ICtI ""t'IL i·.....,.III~Y I' 10 1 0 10 ZO ~40 ~10 JO 10 to 100 10 1 0 10 210 so 40 10 10 JO 10 10 100 10 1 0 10 210 so 40 10 10 JO 10 10 100 10 1 0 10 zo so 40 110 10 JO 10 10 100 10 1 0 to zo ~40 ~10 10 10 10 100 ,.Of TIII(DtSClWlI£(QU,IU(/)OR DltUOlJ),.Of nll(Dt_muAU.II)011 DU:(lD£D ,.Of nll(DlSCIWIU muAU.II)011 DlCUJl(D ,.Of nll(DlSCHAIlG((QUALl£Il OR Dlt((OlJ),.Of TIll(DtJtlWlG((QUALL.{l)011 uiUiiC 10'10 1 10 1 10 1 10 1 :::.-:---:--I·-~·~- 4 __',4 4 ~r-....."""r-.__"~___"I---+-+--+---+-+-+-+-+-I---l I~,--I-.......r--..I,.'-_ ""I.,I--~__I-0;;;:;;1'--.I"1'---__I 10 4 --:>...---10 4 ....10 4 -J"""'~10 4 ~~-=-",4 ~~3~~~~i-.~~~~!~~:•.-::~:--_-~::-----""":::f-'.:-~'"_f--'-I-'-'U U U U .-- ..4 i':4 i 4 .......-4.,.........I r _...f----'-'~r I I ---.--§I ~-----.--.,--.....~.--I I ....,...:-:-:::~ II 10'I=:'-:-1=:II 10'II 10 1 II 10'I.I\.II 10'~~~~~i~"'§'~~-§~~~'~:,,~· . ..... 1 •••., 4 4 4 4 4- I HH-f----t--t--I-1I-1~ I -JUNE 1 .IULY I lUCIUS I If""'ER I --'--OCT i-J;II-++-/-~ '0 1 0 10 zo ~40 10 eo 7Il 10 10 100 10 1 0 10 10 10 40 10 10 10 10 10 100 10 1 0 10 zo 10 eo 10 10 10 10 10 too 10·0 '"10 10 40 10 60 10 10 10 100 '0 1 0 '0 10 10 40 IlO 60 TO 10 10 Xl ...Of TIME OtSCH~E EQUALLED Oft EXCEEDED ...Of TIlliE [MSCHAAGE EQUAl-UD OR [)(CEED(O '"OF TIME DISCHARGE EQUALLED OR EXCEEDED ..Of TIM(DtSCHARGE [QUALi..ED Olt [XCEED(O ""0'TIlliE DISCHARGE [QullLf.D OR [)Q;;EEO(O 10$to 5 10 5 ~~~~~~~!~~~~••• •,1 • __"4 4 ""''''d--1.-l-l--1-++--+----j1--l I I I -,'~NOTES,LEGEND, \.".~\,.FLOW DURATION CURVES BASED ON MEAN ---GOLD CREEK_'0'_- -10 4 104 DAILY FLOWS.----CANTWELL ~1 -==-i -:~OJ •...--'-'-'.=2.PERIODSOFRECORD'_.-DENALI~6 -':::'1"-~1 S '---DENALI,ilAY'951-SEPI966, •4 >,----,-4 _..NOV 1968 -SEP 19BI .:::::r-....I--:l.:.:..~-~\...........,!---'\'\"-.-'-.-CANTWELL'~:~:~:6:~~~\~~~ I -t'''t-rt ...~r--.",I 2 _'-...-----I'-.~•.....'......GOLDCREEK'AUG 1949-SEP19BIIO;~~-J-LI-;:=:'=::::::S.~1O:===l=i-.....10:=1 ~:~="'-::I~:-':"MONTHLY AND ANNUAL •:::=i::--~''''''''-,'"-,-'-----·:'i '-.-~~......--4 .---;-,;;,--.--.- "4"- -.~'>..-~FLOW DURATION CURVES- I I:..-~r~::--,'"-__.SUSITNA RIVER NEAR DENALI I i I [I .1--'-.----..e-,-''-.2 ..-"-.-'SUSITNA RIVER NEAR CANTWELLN~VEII8ER DECEII8ER'"ANNUA r'\.SUSITNA RIVER AT GOLD CREEK 10 2 0 10 20 300 40 ~o 60 10 eo 90 100 10 2 0 '0 0 30 40 ~60 JO 80 90 100 10 2 0 10 20 30 40 ~60 70 80 90 100 ...OF n ..£~SCh"'AGE EQUALL(1)OR EXCEED£D '"Of T1tftl DISCHARGE EQUALLED DR EXCEEDED '"OF TIlliE DlSCttARGE EQUAlLED OM EXCEEDED PREPARED BY:PRE PARED FOR: ~Figure 3.19 -[}{]&OO~&o~[ID&®©@~ R&M CONSULTANTS.INC• •NOINUR.O.OLoa,n.HVORoLoa,n••U·Ry.VOR'-SUSITNA JOINT VENTURE 1!":':":~~< i ....·~·---.-.- 1881 r-l,-, .I-z.;--;-.""':t= i I..,-.-, l~!-- ,.:~=t~I!..,-11-----+- !.- " I I .ii, A •'"•..'OG .,~.:..._ "'OO'_~'>(_"'_"IO.,.,·("I(O OICTO ••• i--I-r-= ."1 •':•.:'...~.~_;.OO':'UI:...: E'a"~-"'i"'.~.='-'.':;"j-_..--._._-_.--·i --~..~.--- . :~.J E'-~~~%=c.,.-'- .;·'-;-:···L:.-'!_~ llttt=;;~i-.-:_C •••".;, -SUS1TNA'8TATION' -+-8UN8HINE' ..---.....-,....I-~ NOTES: 1.:FLOW'DURATION'CURVES'BASED ON'MEAN'DAllY FLOWS. .t.PERIODS OF RECORD:' ~USITNA STATION:OCT.1874 -SEPT. SUNSHINE:JAN.1882'-'SEPT.188~: a.::lEGEND " I I .r',---... ..:...:r "':_~••':.u,:'• - ••~T.M••1IlI ,~ iOHI ...'· ,,'-! "! .,. ,r -I-, ",!'I I I r-.::..:••::....:-':_~...':.Ul~ 'I .,I -r..~~.,:...:..._':_~...~Tm:...- AueueT !-EE3::.~ i·..,. I! ' ......;.:,~1:=·-- ..:..,:..':_:':~'UI.' a.a.M .. 1 "i l --.- :... II P -'"I·. ;~ ":1=== -:.1=' ..:.1=f f--t--l= ,'.!!:'1 •1 ~1 •!.......-_._~. Nav ......,. "i':~- ~A ...U .."Y 1il;~li!lliilil....-..-........-fl ;:....I-~;!"j~~.:..:,::-:..-....-.:_~: .~.....---.-- ~-- :.~~ .--\......L -:::f-ir:r-;;;:~ ~,Lj,'I~.".~"'-'; ..~,:;.;;:;=~~.~~ ~-:..-=:;t:...:.-. ~:~I ~~~~ :i'il3i :~;:lJ;ic.:Lntrt ..£~...,..''''" '.'I I iH!!i,I''i~i ~ w PREPARED BY: ~-:-"=-"-='-""'-=====---='_.=...=== R&M CONSULTANTS.INC. .NOIN••R.a.OLDD.IITa HYDAOLDrJleT..UA~.YDA" Figure 3.20 Monthly and annual flow duration curves Susitna River at Susitna Station Susitna River at Sunshine PREPARED FOR: -[}{]&[ffi~£c [§[ID£®©@ SUSITNA JOINT VENTURE INBOARD ENGINE JETBOAT INBOARD ENGINE JET UNIT DETAIL OUTBOARD ENGI NE JETBOAT PREPARED BY: ---1[~:;;;,;~~!1b======,========:=:====­ R&M CONSULTANTS,INC. JETBOATS FIGURE 4.1 94 PREPARED FDR: SUSITNAJOINT VENTURE AIRBOAT TRAVEL OVER GRAVEL BARS PRESENTS NO PROBLEM PLANING AIRBOAT (DRAFT IS.,APPROX.4 inches) PHOTOS COURTESY OF MAC'S AIRBOATS,ANCHORAGE PREPARED BY: -c:1li"f f;\'/l----':1~._d·~'~==========~ I=l&M CONSULTANTS,INC. AIRBOATS FIGURE 4.2 95 PREPARED FOR: SUSITNA JOIN r VFNTURE MAJOR DESTINATION PORTAGE CREEK INDIAN RIVER YENTNA RIVER COOK INLET ....:.. o"J FIGURE 5.1 PREPARED BY:~r;;---------- ~&M CONSULTANTS,INC.._--____. LOCATION MAP OF BOATING ACCESS POINTS AND MAJOR DESTINATIONS 96 PREPARED FOR: .[]:{]&OO~&'"~®&®©@ SUSITNA JOINT VENTUME Figure 5.2 Willow Creek boat landing. Figure 5.3 Susitna landing. PREPARED 8Y:~/T1-------- ~&M CONSULTANTS,INC. .............oa<n.:J"laT-......,,__D_~IM.I__••_ Figures 5.2 and 5.3 PREPARED FOR: [}{]&OO~&0 ~®&®©@ SUSITNA JOINT VENTURE Figure 5.4 Sunshine boat landing Figure 5.5 PREPARED BV, -.=~~'V"'1------- Fl&M CONSUL.TANTS,INC .............._OI.~•...,__Te _......,_. Talkeetna boat landing 98 PREPARED FOR: [x]&lm~&0 ~lID&~©@ SUSI rNA JOINT VENTURE Coho I I I I'.,.•I I .I I I "1984 I I I 1··'·I I 1983 I I.':F:I·.I I 1982 I I'':···1.I I 1981 I I I I I I I I I I I 1 I i I I I I i I I I I I I I I I I I I 4 10 16 22 28 I 1 9 1:'1 21 27 1 2 8 .4 20 26 JULY AUG.SEPT. 1984 21 --.-. 22lOI I I I I I I I I I I I I I -,I I I :'I II 11 2l 29 ...0 .6 AUG,I SEPT, 24 .---. 18 JULY 12 • 6 I 0.:~~j:pr:{':!!!t·:fi~IW!t;:n ;;it;;.mH:J$i4::t",:I I 1983 ________~~1 1982 :trAP"",';I I 1981 I I I I 24 lO JUNE I Chum 1.0 1.0 Pink I I I·I I I I 0-==1 I I 1983 I I f I I I I I·I I 1981. t"I I I I I I I I t I I I I I I I I I I I I I I I I I iii , i ,,-~1--1- lO ...8 12 t6 20 24 28 I :'I 9 Il 11 21 2:>29 l 6 'u JUNEI J UL Y I AUG.I SEPT. 1984 1982 PR E PA R~D=:-.;.::B:.:..:Y=-:;:..:.==~====== ~ R &M CONSULTANTS.INC. .""'GIN ••.,..OilOLOCII.eTe HYDRDLDCU.T.eUAveVOfl. Figure 6.1 Migrational timing of Salmon based on Fishwheel catch per unit effort Modified from ADF&G (1985B) PREPARED FOR: [}{]&OO~&0 ~[ID&®©@ SUSITNA JOINT VENTURE Sockeye (Red) I I E3 III"I I .984 I·Ir-,==__I I 198~~_I I 1·982I1981 I I I I i ..---,I I iii I I I-.---...--r",--1..;--=-,~----iii .---,i I I .--''-"1---.-j"I I I I I I 21 I ~,IJ IJ Z,Z~Z,Z 6 '0 JUNE I JUL Y .4 I. AUG. zz Z6 )()" SEPT I~., Chinook (King) H:~"000 00),I 1984 H 0"fOp ":"""""0 00 00""'I 1983 I I 00 •'1 d >,,1 I 1982 T T 7 ,I I 13 I I I , 19 25 I I T I 7 I -.------r 13 .----r 19 I ,I 25 31 ~I 6 ,, r 12 , I 18 r 24 JUNE JULY AUG. PREPARED BY;...--_.--~_...---_._-.-. ~ R&M CONSULTANTS,INC. aNOIN ••Fl.OI!OLoo.eT.HYDROLOD.eT_aUAV.VOA. Figure 6.1 (cont.)Migrational timing of salmon based on Fishwheel catch per unit effort Modified from ADF&G (19858) PREPARED FOR: (i{]&~~&0 ~[ID&®©@ SUSITNA JOINT VENTURE Figure 7.1 Alaska Engineering commission twin screw riverboat on middle Susitna River t 1919 Figure 7.2 U.S.River Steamboat,Omineca at Kroto Landing,1917. Photos courtesy of Alaska Railroad Collection. PREP~RED BY: ~''''1--------- ~&M CONSUL.TANTS,INC. Figure 7.1 and 7.2 101 PREP~REO FOR: ,\.-:-VF\JT:~r ~o IV Flow at Susitna Station =119,000 cfs.August 24,1980 Scale 1"=4000 I PREPARED BY: ~F====--"';-'-=---=--=-==----=--== R&M CONSULTANTS.INC. IINOIN.eRS a.OLODI8Ta HVDRDLco.BTa aWRy.VORe Figure 8.1 Head of Alexander Slough PREPARED FOR: GD&[R3~&Cl ~(ID&~©@ SUSITNA JOINT VENTURE Powerline Slough Flow at Susitna Station PREPARED BY: ...JS~~J&t17""-------- ~&M CONSULTANTS,INC. 119,000 cfs.August 24,1980 Scale 1"=4000' PREPARED FOR: Figure 8.2 SUSITNA JOINT VENTURE 103 Side channel at Susitna Landing Flow at Sunshine approximately 39,400 cfs.August 24,1980 Scale 1"=4000 I PREPARED BY; ~';""-------- R&M CONSULTANTS,INC.Figure 8.3 104 PREPARED FOR: SUSITNA JOINT VENTURE Upper end of Delta Islands Flow at Sunshine approximately 39,400 cfs.August 24,1980 Scale I"==4000' PREPARED BY. ~""'1-------- R&M CONSULTANTS,INC.Figure 8.4 105 PREPARED FOR: [):{]&OO~&c @:[ID&®©@ SUSITNA JOINT VENTURE Head of Kroto Slough Flow at Sunshine approximately 39,400 cfs.August 24,1980 Scale 1"=4000' PREPARED.,---..:..BY_:_ ~ R&M CONSULTANTS,INC.Figure 8.5 106 PREPARED FOR: SUSITNA JOINT VENTURE Confluence with Sheep Creek Flow at Sunshine approximately 39,400 cfs.August 24,1980 Scale 1"=4000' PREPARED BY: -6!~r./l--------- R&M CONSULTANTS,INC. Figure 8.6 107 PREPARED FOR: SUSITNA JOINT VENTURE Confluence with Birch Creek Slough Flow at Sunshine approximately 39,400 cfs.August 24,1980 Scale 1"=4000 I PREPARED BY: ~~--------- J:I&M CONSULTANTS,INC. Figure 8.7 108 PREPARED FOR: SUSITNA JOINT VENTURE Confluence of Susitna,Talkeetna,and Chulitna Rivers Flow at Sunshine approximately 39,400 cfs.August 24,1980 Scale 1"=4000' PREPARED BY:~':'"--------- R&M CONSULTANTS,INC. Figure 8.8 109 PREPARED FOR; [}{]&OO~&c~[ID&~©@ SUSITNA JOINT VENTURE Boulder strewn reach at RM 112 to RM 113 Flow at Gold Creek =7,400 cfs.October 4,1984 'Scale 1"=4000' PREPARE D~8_Y_;_ ~ R&M CONSULTANTS,INC. Figure 8.9 no PREPARED FOR; [X]&00 Z6&c @JID&®~@ SUSITNA JOINT VENTURE Main channel crossing floodplain at RM 128. Flow at Gold Creek =7,400 cfs.October 4,1984 PREPARED BY:~-:;---------- R&M CONSULTANTS,INC.____.............v ••_ Figure 8.10 Hl PREPARED FOR: [x]&OO~&Cl§OO&~©@ SUSITNA JOINT VENTURE SUSITNA HYDROGRAPHIC SURVEYS ~":J I I 10....-........ Q) Q)u.. ,E c L ~~'4 I ............igr/<b":J I -I~J:! :+J ctJ>Q) w PREPARED BY: ~'7'''''".=:===..;,"..;.;--==,--,====Fiqure 10.1 Channel cross-section,RM 128.2 R&M"CONSULTANTS,INC. eNGIN••".aeO\..OClI.Ta Mva'-OLDCI.aTa .ulllv.va...· PREPARED FOR: [M]&OO~&"c§[ID&®©(Q) SUSITNA JOINT VENTURE