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HomeMy WebLinkAboutAPA512Susitna Hydroelectric Project Supplemental Report FERC L(~tter of 4/12/83 ¥.....". --~---~--------~- ') Item k ··w'+ Page C and on the River r:S;te C o;ects or. r'9ace h 'roe an ~vents :over d ~ff t ~.+•..k ec s ~'~e ectric Power ~j dn Ice ver on the ;"'10gy) Summary of 1979/80 A(:'l\"ial R~ce,'¥;:n5sa~· DY'l)grCiffi Summary of ',979/80 Frc;eze~· Critical Discharge (0)a~d Power 0 ~(P) at Dunvegan ~1aximum Potential Daily Wate,"L~vel Ranqes in Peace River Effects of Site C and DunvegAn ~,I~oelectric Power P~ojects en the DJte of First I 'n TQwn of Peace River (Normal Discharge' ~-""'~'~,.:;:'c: j't ~';'t.__.;>......."'"..,,,,"'..,..,,......,.--., .)? ._J,,. r f ! I I I I Location Plan Comparison of Observed and Computed Discharge Hydrographs Range of Hourly Discharges at the Town of Peace River with Dunvegan Power Peaking (1000 MW) Maximum Water Levels During Freeze-Up and Break-Up Maximum Water and Ice Levels ;n the Town of Peace River Typical Ice Processes Observed on the Peace River Degree-Days of Freezing,Fort St.John (A) f) Peace River Plan and Profile Peace River Hydrometri c Data for the 1979 -1980 Ice FOrmation Period Typ;ca 1 ~Jeekly Load Pattern for the Alberta Interconnected PO\'Jer System in 1990 Hourly Flows for a Typi ca 1 ~Jeekly Load Patter'n in 2005 Ice Cover Development on the Peace River Peace River Water Temperature Data Peace River Plan and Prof'ile in the Vicinity of the Town of Peace River LIST OF FIGURES AND PLATES A B Al Pl ate, Figure 5 4 3 1 2 C D E F G r )I' ." I \I"".,. '"f,.J , ~J: .,t .J, .J,, I\i,f' I" I j\J I \1 1 ." £•• ilf"< iIf ((I i ( •\1 1 Ii, I I ) 1 July 30,1980 P5645.00 Board Mr J Yu Energy Resources Conservation 603 -6th Avenue SW Calgary,Alberta T2P OT4 Dear Mr Yu Dunvegan Power Project Peace Rivftr Ice Study It is with pleasure that we present the above report to the Energy Resources Conservation Board. Yours sincerely ..~.../J~) ,:.•~4;;.::-.ec...-i-l:.~ R Bruce Elson,P Eng vie found this study to be par'ticularly interesting and challenging. The results of the study have indicated that for all intents and pw"po$es the Dunvegan Project wi 11 be able to operate at any time at its full 1000 MW capacity.However,for a one to two week pel";od in some years,the plant will be limited to a maximum of 920 MW whil~~ the ice cover forms and strengthens at the town of Peace River.It is not anticipated that any'major impacts related to ice will be realized along the river below the project other than the loss of the ice bridge at the Shaftesbury Ferry site. He would like to take this opportunity to thank you and Mr J Cockroft for the valuable cooperation given Acres during.the course of the study and in particular during the preparation of this final report. If we can be of any further assistance,please do not hesitate tocontactus. Toronto.Sllrlll1gton.Calgary,Halifax.Niagara Falls.Vancouver,Winnipeg A~RES CONSULTING SERVICES liMITED Suite 450 ..6712 Fisher St SE.Cal~laty,Canada T2H 2A7 TeJephone403 ..253-9161 Telex 03-825582 RBE:BS Encs ,I .1 .r, f. 'f I'.t' 'f 'J 'J. ,f: " 'I' 'r ,~: ':, ·14 .~ 1 o:} t ".~(I ' ......':,? ! I :] 12 15 15 17 17 18 19 Page 3 3 4 4 5 7 7 9 1 23 23 24 25 2.7 29 32 33 36 38 39 44 45 45 PEACE RIVER ICE REGIME 4.1 Operating Policy for tle Dunvegan Project 4.2 Winter Monthly Inflows to Dunvegan 4.3 Future Power and Energy Demands 4.4 Dunvegan Di scharge Patterns 4.5 Flows at the Town of Peace River IMPACT OF THE OPERATIONS OF WILLISTON LAKE ON THE PEACE RIVER ICE REGIME DUNVEGAN PLANT OPERATIONS AND HYDROLOGIC REGIME 1.1 Scope of Study 1.2 Hydroelectric Development of the Peace River 1.2.1 Existing Developments 1.2.2 Proposed Developments FIELD RECONNAISSANCE PROGRAM :.2.1 Genera 1 2.2 Ice Observations 5.1 Development of an Ice Cover 5.1.1 Leading Edge Stability 5.1.2 Internal Stability 5.2 Winter Water Levels and Crjtical Discharges 5.3 Critical Power Peak at Dunvegan 5.4 Mid-Winter Power Peaks 5.5 Daily Water Level Fluctuations 5.6 Effect of ~!ater Level Fluctuations on Ice CoVers 5.7 Date of First Ice 5.8 Ice Front Location and Rate of Advance 5.9 Upstream Effects of the Dunvegan Development 5.10 Winter Road Crossings 5.11 Spring Break-up Regime TABLE OF CONTENTS ACKNOWLEDGEMENT GLOSSARY OF ABBREVIATIONS LI5T 0 r-TAB LES LIST OF FI GURESAND PLATES SUt~MARY 1 INTRODUCTION 2 3 4 5 ,.. ,II I· ~.. 'J r 'J t·,tr , 'f J, f, ·r L , j r ..' L l!\,." !, 47 47 47 51 52 Page t····iiW Methodology Model Description Model Calibration Model Parameters THERMAL REGIME -METHOD OF ANALYSIS A.1 A.2 A.3 A.4 TABLE OF CONTENTS - 2 APPENDIX A BIBLIOGRAPHY PLATES I., ('•.~...< " , :1 If r ,I.'.".I' ",. ; If: ( 1 t " 'J~ t Ji '1 J Jj ,JI J) J.'~,.}' J, '1 J" ACKNOWLEDGEMENT Acres wishes to acknowledge the cooperation and assistance of the staff of the Energy Resources Conservation Board; Al berta'Envi ronment,vJater Survey of Canada,the Alberta Research Council,and the British Columbia Hydro and Power Authority in the execution of this study. .~... .;,,'-- r I ,.,....;..I·\'."~ I ~F".,f,J (. ,If '-J I tJ " if'f ','; \ (. IFi,: I' i f: .,- .I,r f .J ,L f; \f I {(J l~ , J.,...(f . I. I • metres kilometres cubic metres per second elevation square kilometres .megawatts millions of kilowatt-hours o GLOSSARY OF ABBREVIATIONS el m km km2 MW GW.h / ! t1 ir I 1.(-...I •\, .( {f ( (r .~ ~r r Lr I .....~~l , '" ,,: t • \f /' \.[:' />' . t 1 (. 'f . l:, ,.,'.., ~\ ~~.., ,.J f :; .fI-'r'"¥"'r o SUMMARY -In the case of a II normal II Winter flow year,the plant will be able to operate at 100 percerr capacity except for a very short period of 5 to 15 days during formation of the ice cover at the town of Peace River.During this per;od,it may be necessary to limit plant operation to 96 percent of full capacity to allow the ice cover to develop and stabilize at the town.Once the ice cover has progressed upstream of the town (above the Smoky River confluence) and consc)];dati on and freezi ng of the cover has taken pl ace,the fUll capacity of the plant can again be safely used . -In lIdrier"years,or years of relatively iow mean winter flows, the plant will be able to operate all winter at 100 percent plant Capacity without any restrictions. - 1 This study was done to detennine whether unrestricted operation of a 1000 MvJ Dunvegan hydroelectric development in the winter period would cause ice-induced flooding p}"oblems downstream,particularly at the town of Peace River. The.results of the analyses indicate that there will be little or no need to restrict the operation of the Dunvegan development as summarized below: To conservatively assess this matter,a "worst ll case for plant operations has been used throughout the study.Thi s case assumes that on 1y 100 MvJ or 10 percent of the installed capacity would be operated continuously (base loaded)to provide riparian river flows with the remaining 90 percent meeting daily peaking demands.This mode of operation provides the largest daily variation in winter flows and,consequently,the greatest potential for flooding problems due to ice. '.....,.·~~r.r.I••I'.•l.I~.'..,.."•............".,. "i'!'"q ,. r r r r f r r r J J r !'-..-~ f h •Mare than lOO~MW could be operated at Dunvegan at aTl times except during the 5 to 15 day critical period. •To eliminate the restriction on the last 4 to 8 percent of capacity for 5 to 15 days,Some remedial measures such as minor dyke height. ening through the town of Peace River would be re.quired. - 2 -In "wet"years,which OCcur l,;s than 20 Percent of the time,it may be neces s ary to 1i mi t the p1ant ope rati on to 92 perCen t of fu 11 capacity for 5 to 15 days for the same reasons as explained above. -0 [) In the study reach from Dunvegan to 20 km downstream of the town of Peace River,the only other problem would be the Probable elimination of the use of an ice bridge at the Shaftesbury ferry crossing. The stUdy has also found that the iCe COVer can be expected to OCcur later in the year and more slowly than at present.Under nOrmal climatic and hydrologic conditions,the river downstream of the Dunvegan project can be expected to be completely ice-covered before winterls end.High mean river flows and warm air temperatures Would result in open water all Winter for some.distance downstream of Dunvegan,although the river in the vicinity of the town of Peace River can be eXPected to be ice covered.QUite unusual combinations of high mean winter flows and warm temperatures would result in Open water at the town of Peace River all Winter. If_J" IfII r f· f• f' r r r r r ; 11;,'. J, .f.. .~r. I I I t j 1. ( 1 -INTRODUCTION - 3 Concerns also exist that any potential ice problems could lead to the curtailment of plant operationsa Consequently the Energy Resources Conservation Board commissioned Acres Consulting Services in November, 1979,to carry out this study to evaluate the impact of the proposed low dam development at Dunvegan on the ice regime of the Peace River. 1•I -~e of Stuc4l. Concern has been exprtssed about the impact of a hydl"oel ectric deve 1op- ment at Dunvegan on trle ice re.gime of the Peace Ri ver.In the January, 1977,report entitled IlFeasibility Study,Dunvegan Hydro Power Site U , the Alberta Hydro Conmittee concll:ided that ice observation and evalua ... tion programs should be continued since insufficient data had been gathered to confidently predict the impact of plant operations on the ice regime.In the past~spring ice jams have caused flooding in portions of the town of Peace River located approximately 105 km down- stream of the proposed damsit~, The specific objectives of this studY,as set out by the Energy Resources Conservation Board,were"to: Review all available reports,information,and data pertinert to the study. -Conduct a field program Over the 1979-80 winter neriod desinred to..'...... prov;de i nformati on and data with wh'j ch to carry out necessar / analys1s and as~essments. -Perfonn analyses of the thermal and hydraulic regimes of the Peace River,taking into consideration the effects of Williston Reservoir, Peace Canyon (formerly Site 1),Site C$and Dunvegan. -Using the analyses"determine the effect of various modes of operation of a Dunvegan power ~lant on the Peace River ice cover under a range of winter weather conditions and identify those conditions,if any, Which would aggravate existing ice problems or create new problems. J(II, ',,':t. f' 'f r m" ~ I J J I, J .~ '.f, '~.J , j I j Fit At present,the only completed hydroelectric development on the Peace River consists of the W.A.C.Benne:t Dam and the G.M.Shrum Generating Station some 29 km upstream of Hudson Hope,British Columbia.This plant began operations in 1968 and will Ultimately have a total install ed capaci ty of 2730 Nl4.The reservoi r fonned by the W.A.C.Bennett Dam,called Williston Lake,contains approXimately 42 billion cubic metres of live storage which provides for SUbstantial multiyear r'Jgulation of the Peace River. 1.2.1 -Existing Developments Figure 1 outlines the course of the Peacs River from its orlgln in north-central British Columbia to the Peace-Athabasca delta. Plate A shows the locations of the existing and potential hydro- electric sites considered in this study •. - 4 The Peace Canyon Development,located about 22 km downstream of the W.A.C.Bennett Dam,is currently under construction and will provide an additional installed capacity of iDa MW.The reservoir at this site has been impounded and first energy has been pro- duced. -If the studies ind~lcate ice pr'oblems will be created by unrestricted operation ofa power plant,determine the amount and duration of curtailments of power plant operation necessary to eliminate such problems. -As an alternative to power plant curtailment,if any,identify and determine approximate costs of the most practical means of eliminating such problems. 1.2 -Hydroelectric Development of the Peace River ,~.,,,jj 1 1 F f J f ...J, I -. Additional hydroelectric sites exist on the Peace River in British Columbia below the Peace Canyon Development.However, for the purposes of this study,only the site identified as Site C by the British Columbia Hydro and Power Authority has been incorporated in this work.Site C is about 84 km below Peace Canyon as shown on Plate A. 5 '1' 1 .2.2 -12:sposed Deve 10Ements The proposed Dunvegan Development is located about 127 km down- str~am of the provincial boundary and 105 km upstream of the town of Peace River.The feasibility studies completed in 1976 proposed that"the low dam power developmt3nt would consist of 8 units having a totalled installed capacity of 1000 MW at a full supply level of 381 m.The reservoir formed by the dam would extend as far as ,,:he provi nci a1 boundary and have a total storage volume of 16 billion cubic metres.With reservoir drawdowns of 5 mto 10 fit,the live storage Volume would be in the order of about 0.40 to 0.75 billion cubic metres respectively.This corresponds to about 3 to 6 days of storage for a long term average outflow of 1469 m3js.and no reservo;r i nfl ow. f ••••••••Ir,. J lJ.'.•flJ f 1 "I. .[ \...~ I, LAKE FIGURE I • •EDMONTON •FORT MCMURRAY Z <J:~ 1.JJ:r: U ~ALBERTA ~ <! CJ) CALGARY• LOCATION,PLAN PROPOSED DUNVEGAN DEVELOPMENl: N.W.T~ ...lL lr FORT NELSON • BRITISH COLUMBIA 200 0 200 KILOMETRES . ,I ,- , If-f I! 1.£ f.! iii- Aeri a1 observati ons were made from the begi nning of frazi 1 ice produc .. tion and shore ice growth to the formation of a stable ice cover throughout most of the Alberta portion of the study reach.A total of four reconnaissance flights were undertaken,the details of which are summarized in Table 2.1.It should be noted that the ice front did' not advance significantly beyond the location observed on February 7, 1980.No reconnaissance flights were made durinq spring break-up 1arge 1y because it was one of the mi ldest events in recent years. A reconnaissance program was undertaken during the winter of 1979-1980 to augment existing information on ice conditions in the Peace River. The study reach extended from a point about 20 km .ownstream of the town of Peace River to the W.A.C.Bennett Dam in British Columbia. 2 -FIELD RECONNAISSANCE PROGRAM - 7 2.1 -General Ground observations between the town of Peace River and the Shaftesbury ferry crossing were also made du.ring the field tr"ips as well as on April 21,1980,approximately two days after break-up at the town of Peac=River. In addition to the field trips,various local residents and Water Survey of Canada personnel in the Peace Ri ver area \vere contacted duri ng the ice fon~ation 'period in order to monitor the location of the ice front between reconnaissance flights. Discussions were also held with British Columbia Hydro and Power Authority (BCHPAI personnel to e;<change observation information as the BCHPA have been observing i.ce conditions in the Peace River since the winter of 1973~1974. ril..~ '".~4:.•...-'"..~... ~...••..0 1 ~'\•"':\~JI _.•~,.a"f,,A~......III :;:..."".~••;,.~G-'"~~~,---:,...I::,".,e.'\e"......I • ~t=.:~,~4.~.~~~.,~. Extent of Reconnaissance--- .~ 20 km downstream of the tOWII of Peace River to the W.A.C.Bennett Dam 20 km downstream of the town of Peace River to the British Columbia/Alberta border 20 km downstream of the town of Peace River to the British Columbia/Alberta border 20 km downstream of the town of Peace River to the British Columbia/Alberta border ~}ilgi"4!-¥'.'4'\~ TABLE 2.] t¥:!'k.!e;x~ River Conditions Open water With some border ice growth and slush ice Ice front located 44km upstream of the town of Peace Ri ver Ice front located 162 km upstream of the town of Peace River Ice front located 217 km upstream of the town of Peace River ~"It!k.!!!I''l SUMMARY OF 1979/80 AERIAL R.ECONNAISSANCE PROGRAM ~f"'jlmm'l!'ll November 30,1979 Survey Date- December 28,1979 January 15,1980 february 7,1980 .~."'~~.Il!l¥!!'~!5!!l~A§!i ...~ " !f,>~1 I co o " ,;,:., ~ 1/ f) l I I, "'...'-'-~----'"--.'._':-..-~~~ -·tj ::J I I I j I ! !, I r j 1 I ! i j tt J ! i jIlliwiG""ri.··• --~- 2~2 -Ice Observations - 9 The events observed during the development of the ice cover on the Peace River in the winter of 1979-i980 are summarized in Table 2.2 and on Plate B. The consolidated portion of the cover further downstream in the town of Petice River did not collapse despite a corresponding increase in stage of about 1.25 metres. The most significant of the observed events,are outlined below: (a)Ice cover fOt111ation in this reach of the Peace River can be described as a juxtaposition process in which incoming frazil slush and ice pans accumUlate against the leading edge of the advancing ice front.Some thickening of the ice cover was observed immediately above the Highway 2 bridge crossing in the town of Peace River. (b)Telescoping or "shoving"of the unconsolidated upstream portion of the cover above the Shaftesbury ferry cross in9 (1ocated 27 kilometres above the town of Peace River)took place following an abrupt three-fold increase in discharge at the W.A~C.Bennett Dam on December 29 and 30,1979.It is estimated that the 1 metre thick cover fonned initia11y at the Shaftesbury ferry ;ncreased to about 2.4 metres duri nQ thi s period. (c)The "effective lt channel bank along the river was generally formed by ice accumulations on the sloping banks.Shearing took place in these accumulations during the course of cover develop ... ment,resulting in a vertical plane between the grounded bank accumUlations and the floating central portion of the cover. After initial cover formation,some smoothing of the underside of the ice occurred,as evidenced by the decrease in recorded water levels at ~4ater Survey of Canada stati on 07HAQOl at the 1:o\,/n of Peace River.The ice coyer$confined Within the vertical ice banks,followed the water level change without breaking up. r F r f F F, r [ I Ii I- II t ,~ ~ .,, ~" N.' \ ( I ! ! -10 (d)The average ratE of advance of the ice cover decreased markedly as the ice front progressed upstream.Whereas reductions were due in part to air temperature and discharge increases,the re- duction in ice generation area upstream of th0 advancing front appeared to be more significant,as evidenced by the reduced rate of advance from January 3 to 15,in spite of very low air temperatures. (e)Significant attenuation of peak outflows from the G.M.Shrum Plant was observed at the town of Peace River. f F f ·f F r f r [ [ ~ t t ~• ~ .I J ~ i I I I I I 1I I I j lF t I I 1 " 1 1 I ! I I I! 1 I1 I f Difference between Peace River and Hudson Hope discharges decreases as channel storage is depleted Average rate of ice front advance is 11 km/day.Decreasing ratio due in part to ~/armer tempera tures , but also to reducing ice generation area upstream of advancing ice front Peace River discharges decreasing more sloWly than Hudson Hope due to channel storage between stations -11 Twenty-six kilometr.es of unconsol i- dated ice front thickened due to three-fold increase in discharge. Consolidated cover in Peace River remained intact with stage increase of about 1.25 metr.es due to dis- charge increase. Stage rise at Peace River is due to backwater effect of advancing ice front.Discharge measurements at Peace River are no longer reliable Inflow between Hudson Hope and Peace River averages about 90 m3/s Comments Total stage.increase of about 1.0 over open water level experienced. Average rate of ice front advance from La Crete =23 km/day Average rate of ice f~ont advance is 8.5 Km/day.Largelange of daily ~!schargeS from 800 m Is to 1~7Q m /s at Wil~iston reflected it.stage changes of -0.25 m at Peace Ri ter; i.e.attenuation of short durati~, changes is appreciable due to channel storage effects.Lag time also appears to be increased. Average rate of ice front advance is 11 km/day.This rate is no doubt sustained by prevailing low temperatures. Average rate of ice front advance is 1.7 km/day.Reduction is due to both warmer temperatures and much reduced iCe generation area upstream of ice front.An approximate in ... verse re 1ati cnshi p between di s.- charge and air temperature is noted during January and February (due probably to power demands increasing with decreasing air temperatures). r1ean Daily Air iem- perature at Peace River °c (std.dev.) -16.4 (12.0) -9.2 (6.4) -23.4 -3.9 (4.4) -9.9 (3.1) -11.7 -3.3 (5.9) -6.5 -12.1 (2.5) -28.7 (8.1) -26.1 (7.5) -10.:-1 (8.6) Mean Oaily* Discharge at Hudson Hope 725 ::60% 1048 ::56% 453 400 35% 1191 :12% 823 1?76 +23%,..-87% 1464 36% 1111 +35%-60% "----,, SU~~RY OF 1979-1980 FRErZEMUP EVENTS Mean Daily Discharge at PeRce River 3 +m Is (-t) 1479 ::8% -** 901::72% Event First ice on river at Peace River reported by Water Survey of Canada Pe.riod or Date NoV 19 -Pre-ice condition with Dec 4 relatively constant discharges Dec 5 -Ice front at La Crete 1370 ::16% Dec 11 Ferl"y crossing; 300 km downstre~m of Peace River; Discharge frOm Williston Lake decreasing Dec 12 Dec 24 Complete freeze-over at Peace River OCcurs Jan 3 -Ice front advances to Jan 9 Dunvegan (km 100)as discharges conti nue to increase and air tem- peratures decrease markedly Dec 21 -Stage at Peace River Dec 23 ri ses about 0.9 m; discharge continues to decrease Dec 25 -Ice front advances to Dec 28 km 44 upstream of Peace River.DisCharge is nearly constant during period Dec 29 Williston discharges increaje abruptly to 1200 m Is on Dec 30 Dec 30 -Ice front retreats to Jan 2 km 32 upstream of Pe'.1ce River.Cover shove from leading edge to Shaftesbury Ferry (km 18),thickening from about 1 m to 2.4 /I'~km 18 Dec 3 -Ice front advances to Dec 21 downstream of Peace River;discharges con- tinue to be decreased from Williston TABLE 2.2 Jan 10..Ice front advances to Jan 15 km 175.Discharge in- creases slightly but varies little.Low tem?eraturescontinue, but with warming trend Jan 16 -Ice front advances to Feb 7 km215.Mean daily discharge decreases slightly,bllt varia- bility increases. Tempe;--atures rise and fall appreciably;n period. *Hudson Hope disCharges lagged two days to account in some measure for travel time between Hudson Hope and Peace River. **Discharge measurements at Peace River after this date unreliableduetoiceeffects. f Fi' " \' r ,f o .'«'eib .....• At present~the flow in the Peace River is influenced greatly by the operations of the G.M.Shrum Generating Station at Williston Lake. Hourly flow releases have varied by as much as 1000 m3/s in order to meet the needs for el ectri C pO\AJer in Bri ti sh Co 1umbi a on any given dayo To assess the influence regulation of flows has had on the develop- ment of an ice cover in the Peace River,a comparison of freeze-up data before and after the construction of Williston Lake was made as presented in Table 3.1.Clearly,the marked increase in daily dis- charges dur'j ng the month of freeze-up due to flow regul ati on has had a great influence on the timing and duration of freeze-up in the Peace River.In view of the 'similarity of the air tempel~atures,the diff- erences in c1imat-ic regimes -between the t\'JO periods can be ruled out as a major causative factor for the observed differences. Further evi dence of the capabi 1i ty of vIi 11 i stan Lake to control the winter flows in the Peac~River is seen by the comparison of daily discharge on the date of complete freeze-up at the town of Peace River. Since the construction of Williston Lake,the mean discharge has in- creased from 464 to 1275 m3/s. It is evident that regulation has on average extended the open water season at the town of Peace River appreciably and has reduced the average duration of freeze-up.This is largely due to the freeze.-up period being delayed from November to December.December,as shown by the temperature data in Table 3.1 51 is significantly colder on average than November~and thus the volume of ice required to produce a complete cover on the river can be produced in less time. Of further interest is the greater variability in the dates of first ice and freeze-u!-'resulting from the increase in variability of the di scharge with regul ati on by the G.M.Shl"lum Generating Stati on.The -12r3 -H'1PACT OF THE OPERATIONS OF VlILLISTON f •LAKE ON THE PEACE RIVER ICE REGn~E 'j f f 1 f r r r .f ,-'t' .f f -~~.•.......... .'."',<-':,.........,-, /;,,J ,_.''''''''...'._,' '''"'''''''''''~.~_'_..~~--/ I t ""e'"..... "' It is also interesting to note that the variability of the unregulated Smoky River flows has decreased over the comparison period. -13 date ~f first ice in this case is the date on which ice conditions~ frazi 1 and sl ush ice,were i ni ti a 11 y reported by t'Jater Survey of Canada. Flow regulation has also had a significant effect on the timing and extent of ice conditions in the Fort St.John and Taylor area in British Columbia.Historical records show that since 1968,the mean date of first ice at Taylor has been delayed by about 50 days,from November 24 to January ll;The variability of the date of first ice has also increased from about 8.5 to 15~7 days.It should be noted that with the exception of the winter of 1978-1979,ice effects have not been reported by Hater Survey of Canada for the Taylor gauge since 1974. Prior to the winter of 1968-1969,complete freeze-over in the Fort St" John and Tay1or'area often occurred before freeze-over in the town of Peace River.Under natural flow conditions the date of ice cover formation at Fort St.J)hn and Taylor was therefore largely dependent on whether or not an ice bridging point had developed at some location upstream of the town of Peace River.A reduction in the volume of ice available in the river due to thermal effects and considerably higher discharges during the winter months has since eliminated any significant ice bridging formations upstream of the town of Peace River.At present,initial lodgement of the ice is believed to occur between Ca.rcajou and Fort Vermilion,some .340 to 440 km below the town of Peace River. J; r J i, I'J: t,-".., f f 1 ,i If f' f!:~ f I,.1. I.~.£- l~ I .~~,."---,:-.~-~~} ...... .p:. ~ Mean Nov-Dec Air Temperature at fort Peace St.John River -B.SoC -lS.SoC 20 yrs. i/ '~...~""l1.~~ Mean Daily Discharge on Date of Complete Freeze-Over ...~~~ Mean -[JNOV.-6.50 C Air Dec.-13.3 0 C Temperature n 29 yrs. ~-1 Peace River Smoky River* Mean Discharge During Month of freeze ...Up "'~~~ TABLE 3.$ EFFECT OF REGULATiON ON FREEZE-UP -----t~'<!;)t't-··., Date of first Date of Duration of Ice at Town of Complete Freeze-Up Peace River**Freeze-Over Period ~~..~ ( ~-,;;, Period n =number of years obser-ved m ::::mean value for n years s ::std.deviation *Smoky River flows presented to provide indication of differences in natural (unregulated)hydrology between the pre-and pas t-\~i 11 is tOh Reservoi r periods. **The date of first ice is defined as the date on which ice conditions were initially reported by Hater Survey of Canada personnel. R~ L '\I "< r .- f' f f r I r ~ .. ,r", f f , J .. .J -15 4 -DUNVEGAN ,PLANT OPERATIONS AND HYDROLOGIC REGIME 4'"-QPerating Policy for the Dunvegan Pro>;ect The daily 'winter flow regime at the town of Peace River will be determined principally by power operations at the Dunvegan Hydro- electric Project some 105 km upstream and,to a lesser extent, by inflows from the Smoky River.For the purposes of this study it was assumed that the Dunvegan Project would be used to the fullest extent possible for meeting peak daily power demands in the Alberta interconnected power system.That is,large daily fluctuations of power flow from a minimum riparian flow to the max'imum installed capac;ty can be expected to occur on a daily basis as Dunvegan follows the daily system load pattern.One generating unit at the power plant operating at 2/3 to 3/4 of full gate discharge was assumed as the minimum practicable operating discharge,resulting in a riparian flow of 300 m3/s (iDe ..approxo 100 MH). The daily flow pattern at Dunvegan will occur at the town of Peace River and points further downstream it although some modifications to the timing and magnitude of the peak discharges can be expected. The amount of modification will be dependent upon the effects of channel storage and friction in the intervening channel and,to a great extent,upon the daily operating capacity factor at Dunvegan. The daily capacity factor in this case is defined as the ratio of the mean daily discharge to the full capacity discharge at the plant. With the foregoing operating policy for Dunvegan,and the thorough regulation of the Peace River winter flows provided by the Williston Lake storage reservoir,the operating capacity factor in the winter for the Dunvegan Project over moderate to long time periods will be determined almost exclusively by power releases from the G.M.Shrum Development upstream.Slightly higher operating capacity factors could be sustained by draWing water from storage.However,drawing the reservoir down to gain any appreciable increase in regulated flow would resul t in . a large percentage 1ass of gene\~ating head at -.'1% _(Ctt 1 i I I I I \ I 1 I ,. I () -16 the plant with a corresponding reduction in power peaking capability. This is contrary to the assumed role for the Dunvegan Project.Thus, it has been presumed herein that the Dunvegan reservoir WQuld be used with only minor weekly variations in level to balance differences in both daily load demands and daily inflows throughout the week. Th~existing and proposed upstream power developments at Peace Canyon and Site C,respectively,will not influence the capacity factor as their operating policies would be similar to that assumed for Dunvegan .for the same reasons.Inflows to Dunvegan are unlikely to coincide with the desired flow release pattern from Dunvegan because of both the travel time of flows between plants and the fact that the upstream plants will be following the British Columbia power system load pattern. However,this is not problematical,as a storage volume of about 80 million cubic metres per metre of drawdown in the Dunvegan reservoir will provide ample capacity for dai'iy re-regulation of upstream power releases to suit the Alberta power system requirements.This daily drawdown will not significantly affect the available generating head at Dunvegan. Based on the foregoing assumptions for the operation of the Dunvegan Project,the range of possible flow patterns that might reasonably be expected in the town of Peace River was estimated as outlined in the following sections. 1 i 1 j I, I I Ir \. j Equivalent Dunvegan Energy GH.h 456 418 416 Extreme Wet Year Equivalent Dunvega.n Mean Energy Discharge GW.h m3/s 274 1854 271 1700 279 1694 Norma}Year Mean Discharge m3/s 1115 1105 1111 ,~_. Equivalent Dunvegan Energy GW.h 118 83 80 Dry Year L~INTER MONTHLY INFLm~S TO DUNVEGAN Extreme Mean Discharge m3ls 439 338 328 ~·1onth -17 December January February Winter month inflows to Dunvegan were determined from the 1976 re- port on the feas i bi 1i ty of the Dunvegan Proj ect by r~onenco (Tab 1e :)-25).The range of monthly power flow patterns provided in that report were derived by river basin runoFf/regulation studies of Williston t.ake for various scenarios of power generation development for the British Columbia System and based on 40 years of hydrologic data.For the purpose of this study,the results of the simulations are summarized as follows: 4.2 -Winter Monthly Inflows to Dunvegan The extreme conditions shown above are based on hydrologic events that could occur about once in 40 years combined with the most severe of nine British Columbia development scenarios studied by the BCHPA. These numbers are subject to revision in view of develo!=,ments since the BCHPA analysis;however,the data provides a reasonable basis for defining the mean and low and high extremes for the possible winter inflows to the Dunvegan Development. 4.3 -Future Power and Energy Demands A forecast of the energy demand for the Alberta interconnected power system was obtained from the September,1978 ERCB Report entitled, UEnerg'y Requirements in Alberta 1977 ...2006".These are summarized in the follOWing table.The annual load factors shOwn were obtained from i'he June 1978 El ectri c Util"!ty Plann;ng Counci 1 report anti t1ed "A 1berta El ectri cal Energy Requirements,Total Energy and Total Demand Forecast, r f r .flr I r 'f',"•l' J .f -18 1978-2007".These load factors were used to calculate the annual peak day power demands shown in the :table. FORECAST OF POvlER AND ENERGY DEMANDS FOR ALBERTA INTERCONNECTED POWER SYSTEM f Year Annual Peak Annual Load Factor Annual EnergyDayPower f r~w %G\v.h. 1985 5550 66.2 32180 !'1990 7450 67.5 44040r1995946068.6 568,,\,) 2000 11855 69.6 72270 ;.f 2005 14480 70.4 89290 <' 4.4 -Dunvegan Di~charge Patterns To obtain a repr·esentative sample of the wide variety of power flow patterns that might reasonably be expected in the future!l a variety of combinations of hydrologic conditions discussed in the foregoing sections was considered with the energy requirements for the years 1990 and 2005.For each of the selected combinations,the energy available from the Dunvegan Project was "stacked"in the system for a typical weekly load pattern such that the total installed capacity of 1000 MW (2940 m3/s)or as much of it as possible,was utilized in the system each day.The typical weeklyioad pattern, in conjunction with the range of hydrologies,provided a variety of daily operating capacity factors for the plant.In each case,100 MH was assumed to be base loaded in the system to provide the riparian 3 ...................flow of 300 m Is.Also,the weekly energy was balanced to match the available inflow in dry,normal,and wet years so that large changes in operating head would not occur,as previously discussed.Typical results of the stacking analysis are illustrated on Plate C for the 1990 power demand.This indic;ltes that in low flow years,the full capacity of the plant may not 'Je used for peaking operations ona .".".t tit ..19 if!f Hourly flow patterns at the town of Peace River were derived from the Dunvegan patterns by means of the Muskingum hydrologic flow routing techn i que,whi ch accounts for the effects of channe 1 storage and friction.Limited river cross-section data did not permit the use of mor'e detailed hydraulic flow routing techniques.Plate 0 shows the r~sulting flow pattern at the town of P(~ace River for the pre.vious1y noted Dunvegan hourly power flow pattern for open water conditions. Hourly power discharge patterns from Dunvegan for the example weekly load pattern were derived from the foregoing power generating patterns. Typical examples are illustrated on Plate D for the load year 2005 • 4.5 ..Flows at the Town of Peace River regul ar basi s.In 1ater years,as the load grows,.the full capJ.ci ty can be used even in these years as shown on Plate D for the yaar 2005. To carry out the flow routing,a channel storage coefficient of 0.4 was adopted from an ana lysis of recorded flood hydrographs at Dunvegan and the town of Peace River for open water conditons.The travel time for flow between the points as a function of discharge was adopted from an earlier analysis by Andres (l978).It was found that this method and associated assumptions were suitab~e for open water conditions as demonstrated by the resul ts shown in Figure .2. In this analysis,it was found that the recorded conditions could be . simulated satisfactorily with a range of values for the storage coeffic- i ent (from about 0.3 to 0.4).The uppe.r value was selected for the power flow routing computations in order to provide a modestly conserv- ative estimate of the attenuation of hourly flows from Dunvegan at the town of Peace Ri ver. f r r .' r 2500{1 .' r 2000 F -u I 1JJ.,,.en f ~::1500- w C.!) •r a: cd: :t: U en 1000-,; F 0.. 3000 2500 2000 S2en () :I: l> ;:0 1500 G) rrt 0 "-c::: ~c.n iTtrooo('"')- o 500 II109876 DAYS 5 FIGURE 2 COMPARISON.OF 0.BSERVED AND.l.noro! COMPUTED DISCHARGE HYDROGRAPHS."DOIO -~ - .~ ~ ~--I~, ~ 43 OBSERVED,RECORDED FLOWS AT PEACE RIVER (STATION 07HAOOI) LESS THE SMOKY RIVER DISCHARGE AT WATr NO (STATION 07GJOOI). 2 1 1VMAY22-JUNE 2 1978 "....._....... 1/~ c.-l../V ~.....~----r=/~~V.- L ...........-..... V ~=-..........~....-- l/-'"~APRIL 27 -MAY 4,1977 -------- I;j V-Ip.-1~/-..-::~~JUNE 27 -JULY 5,1969.;;: I:'~~Il/'...............--- t---""l/I IAUGUST19-25,1975V~~I~.......-----:----:::::- ----COMPUTED,RECORDED FLOWS AT THE DUNVEGAN BRIDGE (STATION 07F0003)ROUTED TO THE SMOKY RIVER CONFLUENCE (STORAGE COEFFICIENT =0'4 ). o 3000 500 " r As the presence of an ice cover incl"eases the time of travel in the river,the load flow'patterns derived for Dunvegan were routed a second time with a modified lag-time/discharge relationship.As no hydrographic data is available from Dunvegan for the winter months,the modification was made with theoretical justification using approximate summer and winter lag-times observed for flows between Hudson Hope and the town of Peace Ri\{er.The adopted adjustment factor was 1.6.Typical effects of an ice cover are illustrated on Plate 0 for a normal year.The results of this additional routing analysis were later used to es·r.:imate mid-winter water level fluctuations. -21 The results of the power f~ow routings from Dunvegan to the town of Peace River have been summarized in Figure 3 for both open water and ice cover conditions.These diagrams show the maximum hourly discharge that would occur at the town of Peace River for the maximum likely range of operating capacity factors at Dunvegan (i.e.0.18 to 0.58).It is evident that with Dunvegan operating at higher capacity factors,peak discharges at the town of Pea,ce River will,for all practical purposes, be equal to the peak power releases.Attenuation of peak discharges is seen to increase appreciably for factors below 0.35.The estimated capacity factor for normal winter hydrology is about 0.38. It should be noted that if a higher riparian flow were assumed,the effect would be to increase the attenuation for operation at a given capacity factor. r r r , r r r .. f I, f, ·r ·r J.. ~~,"'1:"'r~........-..,~~ D ..o I ;.fJ \ .'C> ::-,~ n,j " i j r" 1 t ~.'.,,.~"",,,,:~~'!t-li_'~.JT·"_..::~ j." ~;;. 1, 1 .;) " 1 .1 I :::;:;.. NOTEq 2.MAXIMUM BOU~LY DISCHARGES AT THE TOWN OF PEACE RIVER DEPEND ON THE FLOW Ri::LEASE P'"';,TTERN AT DUNVEGAN. I.MAXIMUM HOURLY DISCHARGE RELATIONSnlPS ARE ONLY APPLICABLE FOR AN ASSUMED MINIMUM POWER FLOW OF 300 M3/SEC. 04000 2000 3000 1000 .~ u900 JHaDo~700 :I ~ 6..,",{\w (!J 500 a:: <l::r:u400rn is 300 1-1 200 ..•·-l--l- 100 .-4 .t5 ·6 -7 '8'9"0·3 I I I I,III1I I '2 •CALCULATED BY MUSKINGUM ROUTING OF POWER FLDWS FOR TYPICAL WEEKLY WAD PATTERN. CHANNEL 5TORilIGE FACTO~=0-4 I- IL-~ -I I .t~t--_.J.-+.-I I I I I I 1--~._,.•,--,-_,,_L..J .LJ..1 t1 ",2,·3·4 ·5 ·6 -7 ,8 .g ',0 200 I I I I '00 4000 ,I I .,r--------. f--.•'~"--INSTALlEDCAPPCITY (1\)00 MW)I--t +~+- 2940 ",;,I.SEC~,=__.__ 3000 J.=--;,.==-t==F--t/~C''.'.n;;-;FTIe,.FttF"F-r? 2000 ~-it~:5M;-~mMf~:r:tl ~tt~~:~"'-+~1'''''''''''//+-r--la<.TERM AW.FlDW •/I'n~II 1469 M~f5EC."'../__-f-i--r----~'-f-h fTrl -,..--" taoo !----+-.AVG.DEC.TO FE •FlOW~ 900 -.•"-----r--3 I 1 1 J OO\)----~i:-~'-IIIG M 15EC.fc,~r-1-I I I J 700 --,-~r-~r"--r-..f/', _ 600 ._-_.4 ~~-'EEEE 300 •-,--r::::.-::-;-r--Il~'::''';':::E --:1-.._-..- '+-- --[\f\~;N_"~i;-TO FEa:-;:LO~;-r--I"-t-t--tl-ml-tr-~- 328M3/SEC. w C)cr<:I: t.r CI)a - d \LI U) ;;- ~ III DAILY CAPACITY FACTOR DA!LY CAPACITY FACTOR OPEN WATER CONDiTIONS (NO ICE EFFECT) I-----------------~------, L' -,"'".--',':',"- ICE COVERED CONDITIONS----------- (ICE COVER TO THE VICIN!TY OF THE DUNVEGAN TA!LRACE) FIGURE 3 RANGE OF fUJRLY DiSCHARGES AT THE TOWN OF U-Il'! PEACE RIVER,WITH DUNVEGAN f'OWER PEAKING 1I000MW).M ~ tl ~: 1; t < t L 1 I f1\i} j L liJ··'·······~I'•••'•...• I Ii'"ci .11''1,("~._,,r . " ·1.11 -23 icI l '%¥it (\ 5 -PEACE RIVER ICE REGIME 5.1 -Develo~ment of_an Ice Cover As deposi ti on occurs,it restri cts the channel flow sect;on,ther'eby increasing the water depth at the leading edge until the velocities are low enou9h to permit slush accumulation and continued advancement of the 1eadi.ngedge.The maxi mum wi nter water 1evel s in the Peace f{i ver fora given discharge are observed to be determined by thi s process of cover development. The developrrent of an ice cover on the Peace River is typical of mode'ra'cely steep and wide rivers.When the river water surface has. cooled to the freezing point,fraziland slush ice form,being accumu- lated in a downstream direction until a moving blanket of ice pans and slush filling the river has been obtained.This blanket lodges at some constricted point in the channel to begin forming a solid,stationary ice cover (thi s point is currently near Fort Vermil ion).The upstream or 1earling edge of the ice cover advances in an upstream d'irecti on as more ice is supplied to it from the inflowing blanket.Ho~,ever, typically the front soon reaches a section where the velocity of flow at the leading edge is too great for the slush to remain there,and it is instea.d carried under the established solid cover to be deposited on its underside at the first location where the velocity pE~rm;ts. Subsequent to its initial fo·rmation,the internal stresses in the cover may become too great for it to remain in pI ace as the front continues to advance further upstream.ConsequentlY,the cover com- presses,or telescopes~to increase to a thickness which can resist the developing stresses.Any further increases ;n thickness that occur are then due to either the depositions preViously described or c;i gn;f;cant increases in di scharge..Once the cOver has cansol i dated in this manner and gained strength by further freezing,rather large 5.1 -Development of an Ice Cover -23 5-PEACE RIVER ICE REGIME --' -- As deposition occurs,it restricts the channel flow section,thereby increasing the Water depth at the leading edge until the velocities are low enou~h to permit slush accumulation and continued advancement o.f the leading edge.The maximum winter water levels in the Peace Ri ver for a gi ven ai scha.rge a re observed to be determined by thi s process of cover development. The deve 1opnent of an ice cover on the Peace Ri ver is typi ca 1 of moderately steep and wide rivers.When the river water surface has cooled to the freezing point~frazil and slush ice form,being accumu co lated in a downstream direction until a moving blanket of ice pans and slush filling the river has been obtained.This blanket lodges at some constricted point in the channel to begin forming a solid,stationary ice cover (this point ;s currently near Fort Vermilion).The upstream or leading edge of the ice cover advances in an upstream direction as more ice is supplied to it from the inflowing blanket.However, typically the front soon reaches a section where the velocity of flow at the 1eadingedge is too great for the sl ush to remain there,and it is instead carried under the established solid cover to be deposited on its underside at the first location where the velocity permits. Subsequent to its initial formation,the internal stresses in the cover may become too great for it to remain in place as the front continues to advance further upstream.ConsequentlY,the cover com- presses,or telescopes,to increase to a thicknes5 which can resist the developing stresses.Any further increases ;n thickness that occur are then due to either the depositions previously described Or si gni fi cant increases in di scharge ~Once the cover has con~Dl ida ted in this manner and gained strength by further freezing,ratner large .."=.~.,·1.1iUl'lllttIl1f.'.'..'Il._.IU\MWl~,..,..~..,,"..""'---...'.(; fr~ \ .tr Ie j II I f I I f I I I j II Il~' I II L,I,.~ if discharge increases are required to disrupt ito Subsequent to its formation and consolidation,the under surface of the ice cover becomes smoother due to the flow under it,and the water level decreases slightly for a given discharge.This process has been reported by a number of investigators.(see Michel,1971).Typically,the dis- charge capacity of the ice covered channel for a given water level might increase by 25 percent. VFr=/9H"=O~1541 l-e -24 5.1.1 .,.Leading Edge Stability - The observed hydraulic characteristics of the Peace River channel and experience with increased mean Winter flows due to regulation by Wil1·iston Lake suggest that the prevailing processes will not be altered by further increases in the instantaneous flow at the time of cover formation. This suggestion has been born out by subsequent analysis.However,with the increased instantaneous or short duration discharges,due to power peaking operations at Dunvegan,the process will occur at increased watp.r levels~with resulting increased ice cover thicknesses. As noted above,the maximum water levels in the town of Peace River. occur as a conC\equence of the requi rement for \'/ater depths which wi 11 yield astable leading edge as it passes through the town.The minimum required depth for stability is de·;ined by a dimensionless ratio cailed the critical Fraude number which is defined as follows: where V :::velocity at leading edge H =depth of flow at leading edge 9 =gravitational constant and e ~porositY:-T ice blanket,normally between 0 and 0.73 . This relationstip has been derived from theoretical considerations which have been amply supported by laboratoryexpe~iments and obser- vations in other rivers and channels.If the Froude number at a given ....... I I .~ "(, .J ! ., I I I~It t I .~..., •t-......• r \,~ ~( ~i .~- Ana lysi s of the "internal stabfl i ty of the i ce co~(er at the town of Peace River was under~aken to: --25 river section is less than the value indicated by the foregoing equation, the ice front can progress.If it is not,then the water depth will increase as described until the Froude number is equal to the indicated critical value.With porosity normally varying between 0 and 0.73, the normal range of c ...·itica1 Froude numbers is 0.154 to 0.08. 5.1.2 -Internal Stability Based on observations made during the field reconnaissance program and on subsequent analysis using available river cross-section data, the critical section for leading edge stability .was determined to be near the bri dge crossing sect;on some 800 m upstream of the Water StJrvey of Canada gauge.Hence,the use of the channel width at that section in the analysis rather than the gauge location section width. Froude numbers at the Water Survey of Canada gauge (NO.07HAOOl)in the town of Peace River have been det\::rmined under winter conditions for a period of 22 years,as shown in Figure 4.Data obtained at time of spring break-up is included,as the same staging phenomena prevails at that time as well.Clearly,the range of critical Froude numbers typical of experience else.where envelopes the Peace River data with the exception of four break-up points.These points lie closer to the open water rating curve for the gauging station,probably because of the volume of ice at break-up in these years being too small to achieve the necessary staging.There is,however,no way of confirming this.In any case~it is not of concern for the purpose of this study as the upper boundary condi ticn of the data corresponding to a Froude number of 0.08 is the more critical envelope.This must be conservatively adopted for assessing the critical ice condition dis- charge value for the 'town of Peace River. Cl' ·f ·J ·J ~, I, \f -.-.. I ~{r {\r ( ((, r IJ IJ ( t , ( {f , "f {~"i (' 'f '"(r n ell' C) .........'ioIj"........_.........- ~'_'t~ ,~'.~>....... -~ 7 (OIB)2/3 ~-.....-,.,, .~ ~~ ~ 6 ~ ADVANCING ICE FRONT __ ............-.~""'......... .'!!.~ -,... o --~., 5 .c FRE.EZE UP DATAJ.19511 a.958TO 0-BREAI<UP DATA.1978/1979 ENVELOPE CURVE- ----.. -~ 4 .--......., o -~ --.. .~ 3 o ...-- ~ ._-,.....,--"""""". ~..' 2 ~~~~~."~--()~x,y ..-1 ~..RIVERBED'.Q .':J"I I FROUDE No.::-y....=JL I . JgH -e'i H 3/2 WL=WATER LEVEL B=RIVER WIDTH .~451 M g=9·8 M /SEC/SEC H=(Wl'-310·0)=C (QI B)2/3 Fr =(1/0 3/2 )v'g:0'080 ........,~.-.'_",.-.. n~ "'~iii'~'- ~ ~ 1- o•~~ II '- ENVELOPE CURVE ••I CRITICAL FROUDE No.=O'08 {E =O·73} "-~~ u o L I I 'J I I I II I I J '--l.....-L-.1., _I I I I I _.1.I _ o 1000 4000 5000 6000 7000 8000 9000 (Q) --.-, . I I I /I I Qttt\"';) :"\" \<Q "Ol~ '-: ~'?x FRPU~E NO •.•.•CH54 J'I-E 1..I~O (E=O)~'"~I •r \ 318 316 317 313 310 314 312 315 31J ~ ~ enw fr f- lU :E I0::--=WO >0~«O::;x: w ......0°<C. W 0 0.. 2 ZZ_0 ..JI- W·ce( >1-WcI) ..J . 0:::0Woo 1-.:,,;~;> ~- ':2: :::> ~ X« ~ ~-.,.".-,..~;",~ Q ,tr&~au -r----:~_MOJ'«....~;r C;._~.~_'''''"':<..-, "s:::0» f11Xrn--NS:",es:I c~-0.]> »--fzlTt 0::0 (Dr :::0 fTl.",<»1T1 A r ,(J) Co :Dc ;0 Z G> r:c:1 IJ'6ft'C .•••••~Q •DISCHARGE IN M 3 /SEC.I t ,I I j J I" MC)h) -27 From the water surface and iCE:cover profiles calculated for discharges of 500 m3/s to 3500 m3/s,it is possible to construct water level/dis- charge relationships at various points through the Town,both downstream and upstream of the Water Survey of Canada gaugeQ Figure 5 shows these relationships for the cross-section adjacent t the West Peace River dyke and the Heart River confluence.Included in Figure 5 is a corres- ponding envelope curve for the mean ice surface elevation. *This information was obtained from discussions with representatives of the town of Peace River. 5.2 -.Hinter Water-'Levels and Critical Discharg.es Typical results obtained from the analysis are illustrated for a discharge of 2500 m3/s on Plate F. The latter information was requ'ired to determine water levels within the existing flood protection dykes along both banks of the river. The West Peace River dyke is approximately 2.2 km long and is currently constructed to a level of about 320.5 m as shown on Plate F"Itis understood that the 4.5 km long dyke,along the east bank will be raised this year to a crest elevation of 320.3 m at the mouth of the Heart R".-k"1 vera -confirm'that the governing ice process would nat change with increases in peak di scharge that mi ght be rea'}i zed with the Dunvegan Project. -obtain water surface/ice cover gradients for the river reach through the town of Peace River. The analysis was carried out by means of a mathematical model which simulates the thermal generation,upstream progression,packing and thickening of frazil ice at formation as well as the accumulation and jamming of ice.The associated backwater effects along the ice- covered and open water reaches of the river are calculated in the mathematical model using the standard step method.Application of the model to a wide range of hydraulic conditions has proven its capabil- ity to simulate fragmented ice coVer behaviour. --_.----.,.."..,,---'._-------------------------- { tf l r 1 [ f If ,f: I r l f ~~ r 'f""", t 'f {\f' f If"<I . ", f lr,( '~. ,rr o ..'CHi.t::i: r 7 FIGURE 5 (Ii -~ 6 MAXIMUM WINTER WATER SURFACE ELEVATION 2KM. UPSTREAM OF HIGHWAY No.2 BRIDGE CROSSING. (ICE COVERED CONDITION) MAXIMUM WINTER WATER SURFACE ELEVATION AT WATER SURVEY OF CANADA GAUGE No.07HAOO I (ICE COVERED CONDITION) OPEN WATER LEVEL Ar WATER SURVEY OF CANADA GAUGE No.Q7HAOOI. DISCHARGE (M3/SEC X 1000 ) MAXIMUM WATER AND feE LE\IELS IN THE TO'NN OF PEACE RIVER' I ~2700 M3 /SEC. ----....---.:.....,-I~---I 345 CRITICAL DYKE CREST ELEVATION 3~ 1M FREEBOAR~. MAXIMUM ICE SURFACE ELEVATION 2KM.UP$'T'REAM OF HIGHWAY No.2 BRIDGE CROSSING. 'I DEFiNITION.SKETCH 324 320 322 1 318 316 310 t I 0 I 2 312 314 zo t- § LaJ ..J LlJ - Q Z« a: lJJ....~ r •<·:r ,( • t f<-~<'-!' I If r' I,lr i r ,[r If { l r If r t f , I ;f •:l t 1 J f ., , D m3js 2700 Critical Winter Discharge --•< Increment of Qyke .Hei Qht m o f .i: ir J,_...........- CRITr'CAL WINTER DISCHARGE IN THE TOWN OF PEACE RIVER Critical Dyke Crest Elevation m 320.3 (existing) 320.5 0.2 2800 321.0 0.7 3000 321.5 1.2 3235 322.0 1.7 3455 -29 5..3 -Critical Power Peak at Dunvegan At this location,the critical dyke crest elevation will be 320.3 m upon completion of the flood dyke along the east bank. By combining the foregoing critical discharges INith the results of the power flow routing in Figure 3 in Section 4.5,the maximum peak power ---~-------~-~-~------------~~----------~---~-~~-~-- A criterion of a minimum of 1/0 m of freeboard between the mean ice surface and the critical dyke crest elevation has been adopted. This will provide a minimum freeboard allowance on the water surface of 1.5 m.The critical winter discharge for the town of Peace River on the basi s of these cri teri a is seen fr'om Fi·gure 5 to be abot:: 2700 m3/so If the dyke crest elevations were to be increased while maintaining the same freeboard criterion,the magnitude of the critical discharge would also increase as shown in the following table. The cost of raising the dykes or of other means of flood protection WOt(J d bl?part ofa subsequent phase of the work if required and as such has not been estimated for this report. JI iF f'.ff..iif (If Ir fy If f, [; [. [I tf (f .if \, [ I~ I 1 0 - -I I t''_"".......'_ discharges that can be released at Dunvegan without risking flooding in the town of Peace River at the critical time of ice cover formation there,have been derived.The results of this analysis are summarized in Table 5.1. -30 As outlined in Section 5.1,the critical discharge at the town of Peace River is governed by the requirement for leading edge stability of the ice front as it passes through the Town.Upstream of the ice front, the river will be partially Govered by a thin drifting blanket of slush and pan ice accumulations.These accumulations will decrease in sur- face area density in an upstream direction.The overall effect of this loose ice blanket on peak power flow attenuation between Dunvegan and the town of Peace River cannot be precisely determined. Very large installed capacities could be safely used if the Dunvegan power plant was to be operated at low capacity factors"However,with the prey';ously descri bed Ilnormal"hydrol ogy ~the operati ng capaci ty factor would be in the range of 0.35 to 0.40 for an installed capacity of 1000 MW with 100 MW base loaded.In the Ilwet"hydrology years,values in the range of 0•.40 to 0.50 will occur.Consequently,a capacity factor as high as 0.50 has been assumed in defining the critical peak power release at Dunvegan.This does not preclude higher installed capacities at Dunvegan which could be used to good advantage for peaking in normal or drier years.The optimum installed capacity for the project is a matter of project and power system economics,being dependent upon the fl ow f~-equency and is beyond the scope of this study. Consequently,it has been assumed for the purposes of this study that attenuation of peak power discharges between the leading edge of the ice cover and Dunvegan wili be similar to that of an open water condition. Fi gure 3 i ndi cates that there is 1esS attenuati on of peak fl ows '~or the , open water case than for the case of complete ice cover.The cri-dcal discharges and power peaks for the Dunvegan development have been assessed on the basis of this assumption and the ice front located at the ~ritical river section in the town of Peace River~ (" \",.j ,,' \ j ( i J ~, (,I",.", . J t ftf r{f If If '.[r lr I I{, (I \, ~~I1i(1!l~ J~) I j j I I I ! I I J~ l'~ i I ! I j I J!I , r'~~~ I I 1 :\~\1\' I \jIIIII~ ! 1 I 1 "',~"~':) ~ w --' l,~ _..•..··"·>-4 ~..._,...-~~., .......-.--~ i ! I I i I [ ! i f' I II -=....,.1I'~i .••••.•·_···i •._~~--------------------........~_._----_.'-'. ~"'-'~~.q _.....,....>_.... i "-"!!"'1 _.-~~--". DUNVEGAN OPERATING CAPACITY FACTORS 0.2 0.3 0.4 0.50.6 Q PQ Vq----rrQ PQ p m3/s MW.m3zs !lli.m3/s MW m31S!1!i m3/s MW 5290 1800 3050 1040 2785 950 2700 920 2700 920 5490 1870 3170 1080 2890 985 2800 950 2800 950 5880 2000 3390 1155 3095 1055 3000 10203000 1020 6340 210n 3660 124,5 3340 1135 32351100 3235 1100, 6770 2300 3910 1330 3565 121~3455 1175 3455 1175 .....~....-.-..•""-....~--..--_., TABLE 5.1 CRITICAL DISCHARGE BH AND POWER PEAK (PLAT DUNVEGAN ~~~~~~~-~~~ 2700 Critical Discharge at , The Town of Peace River 3InIs 2800 3000 3235 3455 .~~-'~ Critical Dyke Crest Elevation 320.3 (existing) m 320.5 321.0 321.5 322.0 Note: 1.Based on a minimum of 1.0 m of freeboard above mean ice cover surface. 2.Based on assumption of most severe possible ice conditions in the town of Peace River. 3.Permissible peak power limits are based on preliminary analyses with limited r'iver section data and are subject to refinement when more detailed river surveys have been comp·Jeted. 4.Existing dyke crest elevation taken as 320.3 m at the Heart R'iver confluence (east bank) on the basis of discussions with the Town Engineer for the town of Peace River. 5.Based on 100MW base loaded and 900Mt~available for peaking operations. ~'~.- I Li--, I•~... ,.....:~......""",;,f.'- I ,I .,32 _...__t<:.f As noted in the earlier brief description of ice cover development on the Peace River,a decrease or "se t-back!l in water levels fOT a given discharge occurs with smoothing of the underside of the cover once internal equilibrium has been achieved.This results in a corresponding increase in the dyke freeboard and gives rise to a possible ice formation operating strategy which would limit power peakiflg capability to the previously ta.bulated minimums for a relatively brief period some years. Increases in peak power discharges coul d be perm.itted after the decrease in water levels has occurred.The application of the strategy is described below. With open water conditions from Dunvegan to downstream of the town of Peace River,there is no limit,for all practical purposes,to the peak power that can be used at Dunvegan.However,as the ice front approaches the Town from downstream,increasing w~ter level stages are rea.lized in the Town as previously noted.Peak power releases could then be reduced to the critical values appropriate to the prevailing hydrology.These reduced power releases would be maintained until the ice front had advanced upstream of the Smoky River confluence,consolidation and freez- ing of the cover he.d taken place and lI set-back ll of the water level had occurred.It has been observed that this smoothing of the ice under- surface and corresponding decrease in water level (fora given discharge) occurs within about a on~week period. It is evident from Table 5.1 that a minimum winter power peaking capability of 920 MW ot'"92 percent of the installed capacity is feasible in llwet"hydrology years with capacity factors in the order of about 0.50.For "normal"hydrology years with a corresponding capacity factor of 0.38,the critical power peak at Dunvegan would be about 960 MW. It should be noted that this assessment is based on-the somewhat conser- vative criteria perviously discussed such as the 100 MW base load assump- tions,the peak power flows occurring when the ice front is at the Town, the leading edge stability being controlled by the upper boundary cond- ition corresponding to a Froude number ofO.OB,a river channel storage coefficient assumed to be 0.4 and the attenuation of peak flows corres- ponding to open water conditions. 5.4 ...Mi d..·t~i "ter Power Peaks r... " !r: r if i ! ·f"'I; • J · J · J fl ·r' 1,F I If"., IIf Ir fif"l ' r I I f..·. I r If I I 1 r I I f !I !I . ·r o -33 On the bas'is of the thermal calculations and assessment of the effects of Site C and Dunvegan reservoirs on the rate of cover development as described later,it is estimated that the reduced peaking policy would be required for 5 to 15 days.(The shorter duration corresponds to cold climate/low mean flow combinations at the time of ice front advance through the Town;the longer duration to warm climate/high mean flow combinations.)Peak power releases couid then safely be.increased appreciably,with the limiting peak discharge being determined by the minimum desirable dyke freeboard and the amount of Il se t-back".This phenomenon occurred during the reconnaissance program as described in Section 2.Typically,the Ils et-back ll phenomenon will permit an increase in flow for given level of about 25 percent. As in the case for the ice formation period,the mid-winter power peaks could be substantially larger for small values of operating capac.ity factor at Dunvegan,due to the increased attenuation of peak flows between Dunvegan and the town of Peace River. On the basis of a minimum freeboard of 1.5 m on tha water surface and an increase of 25 percent in discharge for a given stage at the upstream end of Town,the mid-winter power peaks were determined for capacity factors in excess 'of 50 percent.;These are sunmarized in Table 5.2. 5.5 -Daily Water Level Fluctuations The water level fluctuations to be expected in the town of Peace River due to daily power peaking operations at Dunvegan have been estimated. The maximum range of levels would occur for the higher operating capacity factors for which little attenuation of peak discharges is realized, but for which the daily minimum power flow also occurs at the Town. Table 5.3 summarizes the maximum daily ranges that might be expected for mid-winter conditions with both an ice cover in place between Dunvegan and the town of Peace River including the Il se t-back ll allowance,andror open water conditions. (! t . r I I I L II' I j I ! I 1 \; I I, l~ I I j F-~;: 1 \ 1 I r I, ,...Z] •T . G I I I I 1 Corresponding Power Peak MH -34 1120 1190 1295 1410 1495 o 3300 Critical Discharge m3 /s 3490 3800 4150 4400 TABLE 5.2 MID-WINTER DISCHARGE AND POWER PEAK AT DUNVEGAN* m 320.3 (ex;st-Ing) Critical Dyke Crest Elevation 320.5 321,,0 321.5 322.0 *for capacity factors in excess of 50% rr r", ,i r~ 'IlI'f<. ;f If ,l \f {" :,- I :r :, , :r 1 f I . :J, :, . .f J .f .l' .11 l[, \ r ! I Mi(!- tvi lIter Wi';h liS!~t­ ua,:k" of ice COler Tim:of Yea,r----Ice Formation. Period 3.9 3.7 2.3 m 2.2 m 3.7 3.62.1 m 1.9 2.0 m 0.2 0,4 0.6 Open Ice Open Ice Open Ice Water.Covered Water Covered Water Covered 1•1 1.2 m -35 bunvegan Operating Capacity Factor TABLE 5.3 MAXIMUM POTENTIAL DAILY WATER LEVEL RANGES IN PEACE RIVER co 320.5 1190 1 .2 2.1 2.3 3.9 2.4 4.1 321 .0 1295 1.3 2.2 2 ..4 4.1 2.6 4.4 321.5 1410 1.4 2.4 2.6 4.4 2..7 lit:..,..1,,1 322.0 1495 1.5 2.6 2.7 4.6 2.8 4.8 Notes: 3.Water lev~1 fluctuations for ice covered conditions are based on preliminary analyses and are subject to further refinement when more detctiled hydraulic data becomes available. Critical Dyke Power Elevation Peak m MW 1.Range at Water Survey of Canada gauge No.07HA001,800 m down- stream of Highway 2 Bridge in the town of Peace River. .3 2.Minimum power ~low from Dunveganassumeq to be 300 m./S ..(100 MW base 1 Hlded) 320.3 1000 (existing) 320.3 1120 (existing) :r If lr r. 'r I i:r if Iir ~r ( ~r •':r :f 1,~r I d .t t J .J' II.rJ -'ff ~!7 With decreases in flow sUbsequent to cover formation,the floating, central portions of the cover follows the falling water level.If freezing at the shear line3has taken place,the central portion will simply sag until the strength of the bond betweetl the floating and grounded portions is exceeded by the increasing weight of cover support- ed by it.Since theshea~line is a V~t'~y significant plane of weakness at the point of greatest str'ess in the·cover,the cover will always refracture close to this point. If the decrease 'in water level is sufficient,t'ie extremities of the floating cover will come to rest on the channel bed,with sagging again occurring with continuing decreases in level.Ultimately,the cover could assume a position as illustrated in Figure·C;for a low flow stage. Fracturing as shown will occur depend:Jng upon the local channel con- figuration and the initial cover rigidity,to pennit the cover to conform to the channel bed. The thtee stages of typical ice cover development described in Section 5.1 are il1ur ,,,"ated schematically in Fi.gure 6.Of particular note in the second stage of development is the grounding of ice on the shoreline and the subsequent development of shear lines more or less parallel to the riverbanks.This process is the key to the response of ice covers ;'0 most reaches of the Peace River to large variations in water level. 5•.6 -Effect of\~ater Level Fluctuations on Ice Covers -36 o -- .,...,"•.-'J As the discharge and stage increase from a low value,the sections of central cover will simply float oack into place,or develop a "hingeH mechanism,depending~pon the rigidity of the cover.Unless the COver is maintained in the low pcsition for prolonged periods of time,it would be expected to maintain its flexibility and would not need to form the hinge mechanism.In fact,observation of the Peace River has shown that incrJ~ases in the position (tf the cover to ele- vations in excess of the initial formation leve~are possible,as illustrated for a high flCr~J stage in Figure 6.As long as the central cover is :"estrained laterally by the vertical shear walls of the grounded ice,the hydrodynamic stresses in the cover can be transferred \f I . ! ~r 1 i', I ~ J i Ir f J f'- \~I I, fi \' .";",'"',.,·~··t t l \ f ItIt....JI- I -~".'=-J"'.'O:",'-------.-.--.-...' -,:~.•< _Iq~."l'.f')'.o'c...""'"1iI._ - -36 5.6-Effect of Hater Level~t:'l uctuati ons on Ice ,Covers With decreases in flow subsequent to cover formation,the floating, central portions of the cover follows the falling water level 0 If freezing at the shear lines has taken place,the central portion will simply sag until the strength of the bond between the floating and grounded portions is exceeded by the increasing weight of cover support- ed by it.Since the shear line is a very significant plane of weakness at the point of greatest stress in the cover,the cover will always refracture close to this point. - The three stages of typical ice cover development described in Section 5.1 are illustrated schematically in Figure 6.Of particular note in the second stage of development is the grounding of ice on the shoreline and the sUbsequent development of shear lines more or less parallel to the riverbanks.This p~"ocess is the key to the response of ice covers in most reaches of the Peace River to large variations in water level. If the decrease in water level is sUfficient,the extremities of the floating cover will come to rest On the channel bed,with sagging again occurring with continuing decreases in level.U"ltimately,the cover could assume a position as illustrated in Figure·S for a low flow stage. Fracturing as shown will occur depending upon the local channel con- figuration and the initial cover rigidity,to permit the cover to conform to the channel bed. As the qischarge and stage increase from a low value,the sections of central cove.r will simply float back into place,or develop a Uhinge ll mechanism,depend'ing upon the rigidity of the cover.Unless the cover is maintained in the 10w position for prolonged periods of time,it would be expected to maintain its flexib·ility and would not need to form the hinge mechanism.In fact,observation of the Peace River has shown that increases in the position of the cover to ele·!- vations in excess of the initial formation level are pOSSible,as illustrated for a high flow stage in Figure 6.As long as the central cover is restrained later'ally by the vertical sheiir wa.lls of the grounded ice,the hydrodynamic stresses in the cover can be transferred C"'\)t·,(~;"",.'<v;,z;<f~, ".:,~_.._w_.";~~~.l"''''''.·.bl:ll:m'-__''.;''Q...r_.. \J [, .1 f .f F 'f".,.j' "', ,[1'f r "r',,:" 1 . If 1lr If '" ~~ ;;: ~: ~~. l'i' Ii ... r; i:· i '. IT ·am I FIGURE 6 [iJ .-....-------...................._-c TYPICAL ICE PROCESSES OBSERVED ON THE PEACE RIVER. C\ _! lEPJING EDGE STABILITY DETERMINES Co.VER THICKNESS INITIALLY AS ICE FRONT ADVANCES THROUGH SECTiON. COVER THICKNESS iNCREASES SUBSEQLENT TO PASSAGE OF ICE FRONT AS STRESSES INCREASE IN COVER AT SECTION DUE TO BODY AND DRAG FORCES ACT!NG ON COVER UPSTREAM Of SECTION.COVER MAY Al~D THiCKEN BY DEPOSiTiON IF ADDITIONAL ENERGY LOl)S REQUIRED TO CREATE SUFFICIENT STAGE FOR STABLE IrE fRONT AT SOME UPSTREAM SECTION SHEAR LiNtS FORM AS COVER TELESCOPES TO INTERNAL EQUILIBRIUM THICKNESS. FLOW UNDER COVER OR SLUSHiFRAZll DEPOSITS SMOOTH IJNDER SURFACE OF ICE COVER,WITH CONSEQUENT DROP IN STAGE FORA GIVEN FLOW. LARGE DECREASES IN FLOW RESULT iN SAGGING AND FRACTURJNG OF COVER.HINGE MECHANISM MAY FORM. DEPEN[JING ON HOW RIGIDLY COVER HAS FROZEN BEFORE' LARGE DROP IN WATER LEVEL,COVER WILL flOAT BACK UP WITH FLOW INCREASE,EITHER WITH HINGE MECHANISM OR AS SHOWN FOR H1GH FLDW STAGE,. DEPENDING ON RIGIDITY OF COVER, LARGE INCR EASES IN FLOW WI LL FLOAT COVER.COVER WILL NOT FAll PROVIDED ITS IN1TIAl iNTERNAL EOUlllBRJUM THICKNESS WAS DETERMINED AT HIG~FLOW AND fLOW DOES NOT REACH ~TAGE WHiCH fLUATS COVER OUT Of CONFINES OF GROUNDED ICE SHEAR WALLS,-- FRACTURES (HINGES)DEVELOP DURING FALLING STAGE. STAGE I f'E\!ELL-f"MEN'f..- LOW FLOW STAGE STAGE 2 DEVEI..OPMENT HIGH FLOW STAGE STAGE 3 DEVELOPMENT I EFFEcnVECHANNEl WIDTH, 4(BEtWEEN sHEAR'"WALLS: 11 cCc~",~"~~",~ "'-~:-..-'~-'-'''''-----''~---''~~'''~- THIN CuVER By JUXTAPOSITION OF FRAZll SLUSH AND ICE'PANS AT ICE FRONT •c ".~=~__~_~'n C ....'~~."" ==========-==---------------------..-~-oJ ~OUNDE:D ICE I lGROUNDED ~E ""GROUND.Er.Ie': '..,FLOATING ICE.COVER \....~,~'~.;<::~J '::.,f-,:;:....,...~.ON ~~I j.,•••~...- ".•;,.0:...,~,.' I "-w ","=.=_''''1 •:-'..•r <)~'.q .p •t l)o., (j to 'the shor'e across the shear lines.If this contact is lost,the internal stresses cumulating in the cover in the downstream ,direction can disrupt its equilibrium. -38 5.7 -Date of First Ice Using the thermal regime mathematical model and therange·s of input parameters described in Appendix A,calculations were undertaken to In the event that the eov~r develops at a'low'flow and is later· subjected to a large flow,it could be expected to fail because of the loss of shoreline contact,or because it is too thin and weak intel"nal1y to resist the large stresses resulting from the large flows. This is,of course,what happens at spring break-Up as ice covers thin and weaken due to wanning at the same time as spring melt increases run-off.However,this is not critical ifit happens in mid-winter due to variations in power peaking patterns,provided that the critical discharge as previously defined is not exceeded.All that would be expectedi s a dynamic restructuring of the ice cover toa greatef" thickness at a higher elevat~on as occurs at spring break-Up.As noted in Section 5.1 on leading edge stability,both formation and break-Up data conform in determirring maximum water levels.As long as the critical discharge is not exceeded,water levels will be acceptable. From the foregoing insight evolves an operating strategy fal"the proposed Dunvegan Project at the time of cover formation which will preclude dynamic mid-Winter cover disruptions.The strategy is quite simply to operate the plant in the mode in which it is expected to operate throughout the winter,up to the limiting critical discharge (or peak power)value.Under these conditions,the maximum desirable water levels under ice conditions will not be exceeded,but the ice cover will be able to develop with gl'ounded ice,elevations and internal strengths appropriate to the planned winter peaking operations. Continued Ilexercisingll of the cover on a daily basis will maintain its flexibility. /1.•,3'· I\I r w { \, I ;J r;I t I * (J 1 ~ .f \ Jf ~~" f ,J' (. I:r r ~ ;, t IL I \ {~ 'f'"": \ I IT ! o tttnnn. Q • determine the length of open water reach down£treamof the Dunvegan site,with both Site C and Dunvegan reservoirs in place.These calculations provided the basis for estimating the effect of the two proposed reservoirs on the date at which ice can be first expected to appear in the river at various locations. -39 - In general,delays of from 1/2 to 3-1/2 weeks in appearance of first ice can be e;:pected,depending greatiy on the severity of eariy winter temperatures experienced.Similarly,the prevailing hydrology was fow.d to have considerable effect with higher flows delaying date of first ice by up to one month.Tables 5.4 and 5.5 summarize these effects for the reach of the river in the town of Peace River. The 1ocati on of the i'ce front as the ice cover cleve lops on the Peace River has been observed for the past 7 years,since the G.M.Shrum Plant began operating.The results of these observations are summar- ized on graph no.5 on Plate G..Evidently,the position of the front 0'C a given calender date depends markedly on the prevailing climate. The 1973/74 and 1976/77 w'inter saasons were the coldest and wannest of thf:record,respectively$:'and are seen to provide upper and lower bounds to the observed data.The more not'1Tlal cl imati c years are seen to be clustered in the middle area of the plot~ The three curves shown on graph no.5 on Plate G hav~been adopted to represent typical years in which the climate is extremely cold, normal,and warm.The three curves are felt to be representative of the prevailing situation.Although there has been some variability in the hydrology in the period of the record,it has been II nea r ll nonnal,and the curves are thus regarded as being appropriate to the normal hydrology of the river. 5.8 -Ice Front Location and Rate of Advance ~,~;f;;;';';~:"':';'~~:y·::~"'fil:>"'·~'-'.." ~• I f I {r \f"-:'... 1 1r I ~I \ { 10 {~ t I r\~' , t.f Early-December 3 to 3-1/2 weeks Early-Dece~mber Late-December Late-December Early to Mid- January* .-40 Normal Normal Mid-November to Early-December 2-1/2 to 3 weeks Late-November to Early-December foil;d tc Late- December Mid to Late- December Early to Mid- January Climate Cl imate- ~;Jr"'\ ~,~..... Late-November to Early-December Early to Mid- November Early-November Eal'~ly to Mi d- January Late-November to Early-December 2-1/2 to 3 weeks TABLE 5.5 EFFECT ·OF HYDROLOGY ON DATE OF FIRST ICE AT THE TOWN OF PEACE RIVER c' - Date of First Ice (Williston Lake,Peace Canyon,Site C and Dunvegan ReservoIrs in Operation) Date of First Ice Reservoir Combinations Cold TABLE 5.4 EFFECTS OF SITE C AND DUNVEGAN HYDROELECTRIC POWER PROJECTS ON THE DATE OF FIRST ICE IN TOWN OF PEACE RIVER (Normal Discharge) Williston Lake,Site 1 Site Cand Dunvegan Williston Lake and Site 1 Normal (1110 m3;s) High (1854 m3/s) Low (328 m3/s) Difference in timin9 Peace River Discharge *Computations indicated that for this case,ice would appear in the river for only a very short period. t • f J ~. I 1f;' I f I ~ I - IIf ( If'\", ,·rr\ 1 if ,- {f { ,\I i, :i·{ if ....~-_....._--:J-.....-.... .."J..... Examination of these results prOVide some ,'oJ '.•..I :'J-•"'lor _• •,Q'..\~•..1.T u - For the case where the proposed developments are in place,it was nec" essary to as~ume the ice front started at Fort Vennilion and to carry out the analysis from this point using an approximate step-by-step inte- gration p'rocedure.Histor'lc dates of freeze-up at Fort Vermilion were used to estimate the initial starting dates for the calculat;ems to determine the mOdified rates of advance of the ice front. -41 With completion of the Site C and Dunvegan projects,the observed pattern of cover advance will change considerably.Obviously,the front will no longer be able to advance past the Dunvegan Site.Also,the loss of ice generating area both upstream of Dunvegan and downstream due to the thermal effects of the storage may reduce the rate at which ice is supplied to the advancing ice front on any given day in any c1 imati c year.'In turn,the rate of advance of the ice front wi 11 be correspondingly reduced,with its position on any given date being very much altered.An assessment of these potential changes has been made as described briefly in the following paragraphs. The results of this aTlalys;sare presented on Plate G and summarized The 1ength of the open water or ice-free reach in the ri ve.f 011 any given day due to the thermal effects of upstream storages was detennined for each of the three typical climatic regimes by means of the math- ell1atical model described ;n Appendix A.This was done both for the existing situation with only the vJ.A~C.Bennett and Peace Canyon dams in place and also with both Site C and Dunvegan dams assumed to be in place.With this information,the length of ice generating reach was calculated from the known position of the ice front on corresponding days.This is of course readily done for the existing situations where the ice front location·has been defined from observations for the three typical climatic regimes as preViously discussed. :~T~bl-~c c ~-d'~7"'IQ t::::>,J.u all ;)•• ins;ght into a few of the.potent;a1 effects of the proposed power deve 1- opments.In general,ice cover development can be expected to occur iE'rt"~ _'!'!wAD .··.'i·'ur,·{ ~<·<:-·~~"ill:ji.1f_'!ili~rll~~,_'l..-~~:t~'f":'~·r,~':,:,•.,~,.."~,,,,~:-'..;;:>",c_':,( o ~f I ,r .. l ff TABLE 5.6 SUf'iiMARY OF ESTIMATED EFFECTS OF SITE C AND DUNVEGAN,HYDROELECTRIC POWER PROJECTS ON THE DEVELOPMENT OF AN ICE COVER ON THE PEACE RIVER ......--.._..'"""",~..,...•.~.,."-,"",,._., '~.".'"~.'~'··_1 .'-~'-1-J --... ~ -_......, ~~ .•.'~ .......",...-... Early-February (less than 1 km/day) Early-January (less than 1 km/day) Early to Mid-January (6 km/day) Mid to Late-December (14 km/day) late-January (4 km/day) -~-,....-...~-~...----.,..,'"'..-,,..-.......... (with Norma]Hydrology) Reservoir Combinations Mid-December (20 km/day) Williston Lake and Site 1 Will i stan lake,Site 1, Site C and Dunvegan Early to Mid-January (7 km/day) Mid to late-December (12 km/day) Mid-January (8 km/day) Late-December (llkm/day) ."~--' Normal Normal Warm Climate Cold Cold Point of Comparison 2.Time of-;ce front arrival at Dunvegan Bri dge (irate of advance). 1.Time of ice fro~t arri va 1 at the town of Peace River (rate of advance through town). I I I I " Warm Ice front does not reach Dunvegan Ice front does not reach Dunvegan r~.. 3.Furthest advance of ice front upstream of the town of Peace River (time of at~ri val)'. Co I.d Normal 310 km (Early-March) 235 km,near Alberta/B.C. border (late-February) 100 km;Dunvegan project (Early-January) lOll.km;Dunvegan Project (Early-February) +::- N ~30 km;10 km downstream of Dunvegan (Early to t1id-February) 65 km;35 km downstream of Dunvegan (Early-February ) Warm Note:1.Ice front rate of advance var'ies markedly with air temperature on specific dates ;indicated values should be regarded as a;,~roximate norms. 2.Cold and warm year types can be regarded as moderately rare events.,L1 .•...,",I .'..'.......~-( .~ 1 ,i ~J f:- I .-."-......-''\. -t::>o W .-...,'"'""""'.."--1 .".-...- ~~ ---"'-'~ -~ itf/&-""""_~ Mid to late~January (7 km/day) Early to mid~January (4 km/day) I ce front does not Ireach Dunvegan 55 km;45k.m downs tlream Dunvegan (Early to mid-February) Ice front does not reach Dunvegan 65 km;35 km downstream of Ounvegan (late-Febl"Uary) ._.---.......-_,,'..."A.~ Mid-January (8 km/day) Climate Cold with 260 km high dis":(Late-February) charge Warm with 200 km low dis-(Early to mid-February) charge Cold with late Oecember high dis-(8 km/day) charge Warm with low dis- charge Cold with Mid to late~Oecember high dis~(13km/day) charge Warm with Early~January 'low dis-(11 km/day) chat'ge TABLE 5.7 SU~1MARY OF ESTIMATED .EFFECTS OF SITE C AND DUNVEGAN HYDROELECTRIC POWER PROJECTS ON THE DEVELOPMENT OF AN ICE COVER ON THE PEACE RIVER (with Combinations of Extreme Temperature and Hydrology) Point of Comparison Reservoir 0ombinations~H"""il"..."l,-,i-s-to-n-."""L-a"'-k-e-a-n--:d"""'Si te 1 -Wi]1i ston Lak"'-e-,--"""S'"'="'it.,...·.e-·-:::1,.....,------- __._51 te C and Dunvegan 1.Time of ice front arrival at the town of Peace River (rate of advance thi"ough town). 2.Jime of ice front arrival at Dunvegan (rate of advance). 3.Furthest advance cf ice front upstream of the town of Peace River (time of arri val). Note:1 ~Ice front rate of advance varies markedly with c.dr temperature on specific dates;indicated va.lues should be regarded as approximate norms. 2.Combinaticlnsof climate and hydrology can be regarded as rare.The two combinations of tempe't'atur'e and hydro]ogy cons ider'ed were chosen Dn the bas i s of a trend towards an inverse relation between temperature and power demand.That is with lowering temperatures,power releases.from storage (Williston Lake)tend to increase.;i. L"'J :.':....<";·.--->1 :-.----.---·I~,!-,"~ I II .>........-..v.( -44 5.9 -Upstream Effects of the Dunvegan DevelopmenJ. later in the year and more slowly than currently occurs with the existing power installations at Portage ~~ountain and Peace Canyon in British Columbia.For normal climatic and hydrologic conditions, the ice front can be expected to reach Dunvegan shortly before winter's end,subsequent to Site C and Dunvegan power developments. Although moderately rare combinations of high mean river flows and warm ail""temperature fr~Y prevent the ice front from reaching Dunvegan in some years,it can be expected to advance to a point upstream of the town of Peace River in most years.Quite unusual combinations of high mean winter flows and warm temperatures may prevent the ice front from reaching even the town of Peace Rivc~. Under the extreme conditions,the ice 'front may progress far enough upstream to ccuse a backwater effect.r~aximum tailwater levels at Site C would have to be determined by a detailed analysis which is beyoiic the scope af this study.However it is anticipated that these The proposed Dunvegan Development is not expected to have a significant effect on winter tailwat~r levels at Site Co Thermal calculations i ndi cate that there w·nl be i nsuff;ci ent ice generated in this reach to a11 ow the thermal covel"formed in the Dunvegan \"ese:rvoi r to progress much beyond the Alberta/British Columbia border.Except for a combin- ation of e~.tremely cold climatic conditions and low flows in the river, (a relatively rare ~vent),most of the reach will remain o~~n all winter. It should be noted that the net reductions identified for the rate of advance of the ice front a.s a result of Site C and Dunvegan will be somewhat smaller if the Site C project is not undertaken due to its minimal thermal storage.Most of the reduction will be directly attributable to the Dunvegan Development by reason of its proximity to the town of Peace Ri ver o r I J~f,,. I (\f If (' I ~\r i ( \ I 1 [I .....pr. Although the Peace River itse1f tends to dissipate its ice CQV~t'" quietly,the Smoky River has been known to break up tn g \:ery sudden and forceful manner,particula\"ly dur'ing years in wriich there is a significant amount of runoff.When this heppens,a glut of ice is pushed into the Peace River channel.Spr7f1g f100ding has not occurred as lC;lg as br-eak-up in the Smoky Rfver has been relatively mild. The PQt~;ttial for sp\'3ing break-up flooding at the town of Peace River wi 11 b~'.dla ltered by the Dunvegan Development provi ded that power operati ons are modi fi ed as requi red from the time that break-lIp on the Smoky River is imminent until its ice has safely dissipated or beert ty'ans .. ported well downstream of the town of Peace River.Since dissipation normally occurs within a period of about one week and as break-up 5.11 -Spring Break-Up Reglme -45 Other than the town of Peace River,there does not appear to be any other areas within the study reach that will be significantly affected by changes in the ice regime as a result of Dunvegan power operations. However,it is expected that the present utilization .of winter ice roads to cross the river will not be possible in most years.There were several such crossi.ngs located in the vicinity of the town of. Peace River in 1979-1980;the most notable being the Shaftesbury ferry crossing. The town of Peace River has been occasionally subjected to flooding during spring break-Up.The primary cause of this flooding has been the accumulation of large masses of ice in the Peace River channel downstream of the Town. 5.10 -Winter Road Crossings levels would be no greater than those that would be experienced in the area without the Dunvegan Development in place. I I j \ {. \;V \, l'~~l f' {' If \i , ( l I \ , I't ), I, "(,f \ ~:..~-~-•.,-,,,.f ..,o'~• ,.tP'q I.•...•J. occurs \'Jell after the peri ad of wi nter peak power demands,any modi fi ca- tions would likely bea negligible detriment to development of the Dunvegan site. -46 To operate the development in this.manner would l'esultin a loss of heac!and consequently tne ability to meet powE~r system requirements. Nevertheless,flood contro1 benefits may justify the opel"ation of the plant in this mode..This would have to be dE~termined by a detailed analysis which is beyond the scope of this study. With a live reservoir storage of 0.75 billion cubic metres,the Dunvegan Development will in fact have the potential to reduce sprin~break-up .flooding potential.r~anipulation of the storage would be required, however,wi th the r'eservoi r bei ng gradually drawn down dur;ng the month of March to create a flood storage reserveo This reserve would have to be held until it became clear whether or'fl0t it would be.needed"A perfunctory analysis inrlicatss that spring flows would be able to re'fi 11 the storage in the event it WiS not needed for flood contro1. fI ,..., \fi, ( {f' f~ [, (, I , i. t f I J : f !I~; I I ":'....'-\...... o A.Z -Model DescriE!i9n A ~THERMAL REGIME - METHOD OF ANALYSIS ..47 Water released from lower levels in a storage reservoir during the winter months is warmer than the freezing point~and therefore has the effect of removing a reach of the river downstream of it ~om active frazil ice generation..The length of the reach required for the water to be cooled to the point where ice gener,ation can begin (approximately OOC);s essentially a function of three variables,namely,the dis- charge in the river,the temperature of the water released from the reservoir and climatic conditions (mainly air temperature and wind velocity).Therefore,in order to predict the ice regime of a river, it is necessary to determine the cooling rate of the water. Acres has within its library of computer programs,a mathematical model that performs daily heat transfer computations for any combination of reservoirs and/or river reaches.This model was used to evaluate the combined effects of reservoi r sturagf=at Site C and Dunvegan on the ice cover development wi th respect to the date 0)<:'first ice,the rate of advance of the ice front and its time of arrivi~1 at various points along the river.The effects of varying climatic and hydrologic conditions on ice cover development were u1so considered, A.1 -~Iethodo logy Computation of the cooling rate from an open water surface is based on the heat budget approach.The heat budget is expressed as the sum of the major components illustrated and described as follows: .".,... F'., r ( ( i { ( { I {., is the net heat transfer at the vtater surfaces is the solar radiation incident to the water surfar;e is the reflected solar radiation is the atmospheric radiation incident to the water surface is the reflected atmospheric radiation is the back radi at;on or the net energy 'i ast by the body of water through the exchange of long-wave radiation between the body of water and the atmos- phere is the evaporative heat exchange is the conductive heat exchange is the heat required to supply the latent heat of fusion of snow failing into the water or the h'~at gai n from r'ai nfall -_. is the heat gain from flow friction losses in a river reach - Hnet Hs Hsr Ha Har Hbr + + +Hnet =Hs -H +H - H .- Hb - H -He·-Hp.+Hfsraarr e where: 'vI -48 ( (r f 1.\r ,. I f ( (f , 1 {r: ( ( { ......~J •1 ".t.. .\ ~I '"f ,\ a -49 a :::0.8 a t:0.5 to 0.7 ~,MIi.'tt'..',., ;j t.=anY 1 a =a form of local heat transfer coefficient t.=thickness of solid ice1 Windy lakes with no snow average lake with snow J =ac..cumulated degree-days of freezing A value ofa =0.6 was adopted for this ani.\lysi.s. Each of the above components is determined using the empirical relation·· ships presented in Raphael (1962)and Michel (1971).Several other possible sources of heat such as the conduction of heat from within the earth and heat gain from groundwater inflows have been neglected because of their relatively small magnitude. where: The coefficient Ila";s obtained from experience to represent the time average va"lues of the various physical and thermal properties of the ice and water~as well as the highly variable and complex heat transfer between the ice and the atmosphere.Heat transfer at the ice/water interfqce is also considered in the selection of "au.Values of the coeffi ci ent,deri ved from fi e1a experie.nce are: Al though heat transfer f~'om the lower ice surface to the atmosphere actua11y occurs in two stages,the model assumes that the upper ice sur- face is at air temperature and therefore heat transfer occurs frorn conduction alone.Experience has Shown thi$approximation to be accept~ble4' Heat transfer computations for a reservoir also take into account the forma.t1on and growth of an ice cover once the reservoir temperature becomes uniform at about 4°C.The ice cover growth ;s represented by a simple relationship originally derived by St('f~n and simplified by others (see Michel,1971). ! \ {r c (f ( {f ,r ('· f• i \ { ( !· - qc =rate of heat transfer kc =conduction coefficient t.::'ice cover thickness 1 t f =freezing temperature of water Ts =upper ice surface temperature where: -50 .. Transfev'of heat by convection and radiation from the upper ice surface to the atmosphere is not considered in the model.Baines (1961)notes that this practice is equivalent to assuming an overcast sky condition and a strong wind,whereas the average winter cor.iition is one of moderate sunshine and light wind which tends tc produce thinner covers. Heat conducted to or from the lower ice surface.(ice-vt/ater interface) is described by the follow~ng equation: Afte\"performing daily heat transfer calcul ati ons,the model then determines the water temperature at the end of each river reach and also ictentifies the point at which frazil ice begins to form on the water s tlrface.The cri ter;on adopted to determine the length of thei ce gener'ating reach)i.e.,frazii ice begins to form at water temperatures less than about O.loC,was supported by observations made by the BCHPA during theiY~ongoing fie.ld investigat.ion program on the Peace River . The validity of this assumption is supported 'vy data collected on the Nelson River as reported by Newbury (1966).Newbury's analysis of the .data showed independence of ice growth from wind conditions and a trans- fer coefficient very near the generally accepted value for conduction through ice. f ( .~~. ( f ( _t,ry "'«if, A.3 -Model Calibration The computations'to determine the outflow temperature in a reservoir take into account the additi'onal heating or COOling effect caused by daily inflows.It;s assumed that the temperature would be uniform throughout.the entire body of watere This approximation is considered reasonable for the reservoirs below W·~·.<t iston Lake because they have relatively small storage volumes and thus relatively short turnover periods. -51 Calibration of the heat budget model was based on continuous daily water temperature and air temperature data obtained from the BCHPA for two periods -January 1977 to March 1977,and November 1977 to January 1978. Although BCHPA have been recording water temperatures in the Peace River since about 1973,the above periods constitute the most compre- hensive data available for the reach between the vi.A~Cc Bennett Dam and Site C.Water temperatures have not been recorded on a regUlar basis between Site C and the town of Peace River. The objective of the calibration was to reproduce the daily record at Site C using the Peace.Canyon data and the meteorological records at the Fort St,John Airport (with the exception of air temperature)as input to the model.The air temperature data used were thosecbserved adjacent to the river by the BCHPA. A comparison of the computed versus measured thennographs at Site C for the two periods is presented on Plate E.It can be seen from the re- latively close agreement achieved that the model is suitable for pre- dicting the cooling rate from an open water surface. ( ( f (. ,. \i f I i I \ { ( { (,, dye brit ., -52 Channel Hydraulic Data The typical climatic regimes,de$ignated as cold~normal,and warm,were selected from meteorologic records at the Fort St. John airport for the period 1969 to 1979,which covers the period of operation of the G.•M.Shrum Plant.The 1973-1974 alld 1976-1977 winter seasons were respectively the coldest and warmest of the record,and were therefore used for these two extremes. Thel972-1973 period was selected as a normal winter season.A comparison of the accumulated degree-days of freezing associated with each climatic regime is shown in Figure A.l. The ri ver channel between the N.A.C.,Bennett Dam and the town of Peace R,ver was subdivided for computation purposes into three hyqraulically distinct reaches.Relationships between mean depth versus discharge and mean velocity versus discharge were then derived for each reach using data available from the Water Survey of Canada.These are summarized in the fol1owing table. , "",.-- ''4'~,~..,'"",,,,'.......'",..•.~:...,•flo •••• .:,'~,"•'.• •0.•..'.'...'. A.4 ..,Model Parametf-rs The basi c input parameters that \vere used in the model to compare the effects of Site C and Dunvegan storage on tbe existing ice cover develop- ment are outlined as follows: (a)r~eteo.ro 109i c Data (b) ~,:p~~~",~~,. ". 1 \ ,"l l ( (, ( t ft ( (\ [t r,' 600 400 o 200 800 1000 2200 1200 1400 1600 2000 1800 1976-1977 FEBRUARY MARCH 5 1015 20 25 5 10 15 20 20 FEBRUARY MARCH 5 K>15 20 25 5 10 15 20 25 JANUARY 5 10 15 20 25 JANUARY I 5 10 15 2IJ 25 5·to 15 20 25 DECEMBER DECEMBER 5 10 15 20 25 5 10·15 20 25 NOVEMBER. NOVEMBER 510 Ie 20 25 a 400 800 600 200 2000 1800 1000 1200 CJ) :J CJ) ....J Wo- <.!l .~1600 N W Wa:1400 l.J.. l.La -2200 (~ ~ C3 I W W 0::: fBo o ttl ~ -J::> ~ '::;) o -0 \<.1: ,....."'-..-.-......._'-...,.....--.--'~~...-..~..,.-..--.",......,.......-"-----.,~-;~.,---......'--"'\ .,;e.,,,,,,~....-'~."_._. FIGURE AI DEGREE -DAYS OF FREEZING IIPDll! fORT ST.JOHN (A)•un L :-1 ............----------1 I ,I 96 km 2 97 km 2 9 km 2 Surface Area at FSL Mean Velocity t~ean Depth d =.1162 Q~44 V =.117 Q.35 d =~129 Q.44 V =.013 Q~55 d :-;.025 Q_S2 V =.188 Q.29 Total Storage Volume 1.6 x 10 9 m3 2.2 x 10 9 m3 0.2 x 10 9 m3 Corresponding Water Survey of Canada Gauge 07EFOOl Hudson Hope,B.C. RESERVOIR DATA SUMMARY E1 381 m El 462 m 51 503 m 07FD002 Taylor~B.C. 07FD003 Dunvegan~Alberta Full Supply Level (FSL) MEAN DEPTH/VELOCITY RELATIONSHIPS Characteristic Reach -54 W.A.C.Bennett Dam to Site C. Dunvt~gan to Peace Ri ve,- Site C to Dunvegan' where V =mean velocity in metres per second d :<=mean depth in metres Q =d;scharg~in cubic metres per second Plant Dunvegan Peace Canyon (c)Reservoir Data For the purpose of this analysis each plant was assumed to be operating at full supply level.The reservoir ·:torage volumes and surface areas associated with these levels are summarized as follows: Site C r fI c l [ [. [ [ f' f [ [ _..--" -55 Water Tem~ratureData Hater temperatures measured in the G.N.Shrum tailrace in 1976- 1977 and 19TJ-l978 were used to develop a typical thermograph for outflows below the development.This location was the point for' all of the calculations undertaken with the heat budget model. Examination of available records shows that because of its great size and depth,temperatures below i~;ll;ston Lake do not vary significantly from year to year. Cd) - Andres~D~D.,1975;Ice Break-Up Observations and Mitigation at the Town of Peace River;Alberta Environment Technical Services Oivision~October,1975. Andres,D.O.,1978;Effects of the Dunvegan Dam an the Ice Regime of the Peace River at the Town of Peace River; Alberta Environment,Technical Services Division, July,1978. Baines,W.O.,1961;On the Transfer of Heat fr~m a River to an Ice Sheet;Trans.E.l.C.,Vol.5,No.1. British Columbia Hydro and Power Authority,1975;Peace River lee Observations 1974-75;Hydroelectric De~ign Di vi sian,Report No.768,October,1975. British Columbia Hydro and Power Authority,'1977;Peace River Ice Observations 1976-77;Hydroelectric Design Division,Report No.870,October,1977. British Columbia Hydro and Power Authority~1978;Peace River Ice Observations 1977-78;Hydroelectric Design Division,Report No.961,December,1a78~ British Columbia Hydro and Power Authority~1976;Peace River Sites C and E Feasibility Study;Hydroelectric Design Division,Report No.796,May,1976. Doyle,P.F.,1978;Observations of Fall 1977 Ice Packs on the Peace,Athabasca,and North Saskatchewan Rivers; Alberta Research Council~Edmonton,Alberta,February, 1978,interim repo~t. Doyle,P.F.,1979;1978 Freeze-Up Observat;lons on the Athabasca,North Saskatchewan,and Peace Rivers; Alberta Research Council,Edmonton,Alberta,January, 1979,interim report. Energy ResQurcesConservationBoard,1978~.Energy· Requi rements in A1 berta 1977-2006;Report 78-1, September,1978. Garner,L.,1979;Ice Break-Up Observations at the Town of Peace River;Alberta Environment,River Engineering Branch,unpublished report~ BIBLIOGRAPHY -II:II! ! t I.,,\, The Nelson River - A Study of Subarctic Ph.D.Thesis,Johns Hopkins University. Newberry,R.,1966; River Pl"ocesses; Nuttall,J.B.,1974;British Columbia Hydro Site One, Impact on Peace River Ice Conditions;Alberta Environment, April,1974. Raphael~J.M.,1962;Prediction of Temperature in Rivers and Reservoirs;Journal of the Power Division,Proceedings American Society of Civil Engineers,July,p.p.157 -181. Szabon~W.,1977;Ice Break~Up Observations a~d Mitigation at the Town of Peace River;Alberta'Environment,Technical Services Division,April,1977. The Alberta Hydro Committee,1977;Feasibility Study, Dunvegan Hydro Power'Site,Volu~e 1;Main Report;January, 1977. Thurber Consultants Ltd.,1976;Sites C &E Hydroelectric Development Proposals,Lower Peace River Environment~l Study,Volume 1,Development Proposals and Resour~e Inventories;September,1976. Gerard,R.,1975;Preliminary Observations of Spring Ice Jams in Alberta;Proc.Third IntI,Symposium on Ice Problems (IAHR),Hanover,N.H.9 August,p.p.261 -277. Joint Task Force,British Columbia Hydro and Power Authority, Alberta Environmen~Water Resources Service of British Columbia,1974;Observations and Report on River Ice Break-Up at the Town of Peace River,A1berta,during April,1974;October,1974. Ke11erhals,R.,C.R.Neill and D.I.Bray,1972; Hydraulic and Geomorphic Characteristics of Rivers in Alberta;Research Council of Alberta,River Engineering and Surface Hydrology Report 72-1,Edmonton,Alberta. Michel,B.,1971;Winter Regime of Rivers and Lakes;U.S. Corps of Engineers,Cold Regions Research and Engineering Laboratory,Hanover,NQ H.,April,1971. Monenco Consultants Ltd.,1976;Peace River Power Development,Dunvegan.Oamsite,Feasibility of Hydroelectric Development;Calgary,Alberta,June 1976. BIBLIOGRAPHY (Continued) ,. ,.·10 _~Jt ---I~., ~\ 'I~, i .," PLATE A "...;, ;1' 1"__ '--'" :,,, ,~..... 1980JUNE " ,t,,"'''p ~~,,\l " :.::o.'~"('.•.....\. :'.\t' RIVER AND PROFILE ~ PEACE PLAN 30 0;--'"......_.__•30 KILOMETRES_"'_:tr2 50 KILOMETRES E -s'"iT] ~ENERGY RESOU~CES CONSERV.l\TION BOARD •DUNVEGAN POWER DEVELOPMEr~T ICE ANALYSIS /?'A::?CJp;~p.cr:~.f:S-"-:::::.-._~'---AcRES SCALE A SCALE B ~~~w i::< 700 GOO :lOO PRDPOSEO DUNvEGAN DAM PLAN (SCALE A I _...~i ,,~,..,...- i ...l,t ..~ ALBERTAr Ii 1 .1,.~-.,.,"'~-I;" I""\.',.w:'"",,-\:- ""-\' ~. '::," .BRlTISH COLUMBIA f SITE C (PROPOSED) I 1 .PEACE CANYDII DEVF.lOf>t>'£NT (!)\IOER CONSTRUCTION) ,'.'f''''\:...;~ •\~<:J~\ B;~·_""'J.1Y~~,.,..',,:."....~~.~'.,->....''''',:~....:::.~l\.\l.J:.. 1"<;••••,-.'J'''~\\\,....~·~.h.;:l;}.,.•.--J,)'}<,,.'.1".-.',"'"--l~.·~l;··.."'~-\·~~t:,·'~"",.:i::~'\~ "\';:1-.'i.~';·,.r-" .0,','':"~~d\\'\.t',{:., 'I...'~:l.it';"',~~','TI~'},2j ;-''V: '••',"1 r·~'.-'/~..''t<t"......."'..:",~.•':"li~. "' ....u.,. '..::.......' N "-~;tJ.i,._'.,~.'-(.i_'.~".~~,~.'f'~t::::::"...J:><t~;:~~~LJ.to.;(;~.4.fi':,.u4'••:'~;::t ..'.'~.,'""~0 -....._ •f~'"_ ,,,.~-.,~.,....!;~'...e'~"'"~.1 ' "1\." ':..~''!".\''',.1"\-1 ...~.'{'l".I.,."!j ...."..,;"1 J!L ".'~\•'''~'1 ~(.....,.•.".~'......\"]'",-~-~.'.,...~.'1..".~n j'"r n,'uo't,'",.',,~!--'\,.-',.....~,.-. ,"':\i .~,'.,'lA"..,':"....\1'":-:,....'.::'-I'~,,.'\.%-f",,,~':'. ¥-.......:~::·t I ,:,',"~,..~,~-:-..7 !.J ••"".'-~~f ~••,u ..'.~"':;.~'~_.:f ~:j~'.:~::.~;-:'~:~. ..,...,-.¥,,~'....,.y ..',,:"',. ..."........,,",~,~,......-.;-,"'";.'~:-.....~!' ":."',.~;.,.~••'..1 #-,...,.""Cf ,~.;'\·.\t.....~-,jOlt "~... •~"t"'~.c.ni;h\",\.("1 ,'!~.~~.,...~"C"1 ..p~'"~'\s~,.a£,L '''iIl \.~.....~.....,"'"'......,.llC_..~N,:.·~,·"-~,...i','T~~..",l~;~......:.:;''f''.)'",'a-"'}'"•_.k ',~,•r,...·.,T'.~~---'_.r :1..~#".,,~..:..~"""~'::~;"";,'l~~ :........4:~..,"~id':~'j _~~..-~:".,,JIoOo.:"..,~_.-'t '\..~,~'",'......f .....::1 ,~~lf:"."·ttt..:·~~+~,;'.~t '-.'.....;zM;\.•.,;t~:I".,h~::~~~:-l- .....'.~,>4 ,.·f ...... '..\ .,. '"_'f!i -$I ~.•. " WILLISTON .J'\ LAKE -f. r'W.Ae IlENNETT DAM FSL ~i G ~PORTAGE:MOUNTAINOEVf:LOPME/>/T :::- ~'.. "«\P'"'", >--:," .,. -.....\.' 700 l ....-lr· ". GCll '.,."~~<'""',,' ~,'q....\~ 500 400 .... 13:=w ~ zo i=~ ttl -J W ~1 , ~~;..,~ .;;0;-do '~".~'T""",;,.~~I"'~'.~f ;,.. ~O,7~",... .,~'"''... .. "t:..••_):.", ..-- .~~ , "t",--/'~\::..f ~..~...~'"'~"::"" •~:(""l~•• ,.~..."':..".~~.o;~/"..'.:.._~',",.~~...-l- ~''':'\,:.,..:r~.'''-, A ',:T~;'..;~...j.:'~": -.~~,·~C~'.,~..",::~,:•.. ~,'"..",,(:~-;:.',...t .~:.;:...... ..,~,~'",~~.~~.t~~'''';''.':.. I~o,II ~:r~,t Ii'S.'_',~..:t.ii.,__,.•....."...:. j,04 ~i,,~,oJ,,.."t\.,.....,,"f·~,;;,./._,,-<:,"",'-••,. ~~:~""'~!Jr...':'-'.~~~--. -.....'1 ,",'", '...-',.,~r .;:"<..'~.\ ... ALASKA HIGHWAY (BRIDGEIATTAYLORI I I I 00'/"CLAYHURST fEARY ~._.HIGHWM No.2 SHAFTESBURY FERRYIBRIDGEATDUNVEGAN I-400 •~•l -!-'-''"--r..~-""'"'''-----~-..".""". »oJ L_'_._.,I'1_[-,1..,I PROFILE '''''''' IIIIi ,.eMTa !'!.=etI ..11 ."~."__,,".,,-__'.0,'_..__~................"_>r~"..,.....;_w __~","";-W""""""",·'" l FEBRUARY lO J5 20 25053'1I 1980JANUARY 10 J5 l!O 2531 DECEMBER1979NOVEMBER 11 f II -.-- r!I ,I ;! I IIH I , 1 1 ~T 1 i !f ; II N-1ITI ' Tdl I '·1 If .. II I I r TIl II II 'H "~,I .II ~ ih w_flO cru:>•...~ <I 0It:l-~~~a:-10...~ a'1t:<!i!--20>'ii:~W,~-~.-30Z~.~ -~~-~O ..,......-,.__~~.~_,.,.,._.,.,~..__..~."~_........,•__p~_.•_•••,:-,....-=-,~......,.e....·__'_''''~_''''...,....~'"'._".~,~........_.....-~~......~_~_~.....,,'~~,.~4.>_'~~'W""""""~"=~~~""~_~_"""__'~~""""".....,~~__•-".,.~--""~..---'--'-----~-~-7-'~-.---~--..~-'~--'--~~-~~,·----------'------~----'- <"i ~ ,, l j l J ~EI~ ) ... I i l-~',~""'lJi...r- ~ ~;.' I. PLATE B o..........._-."""'T" JUNE 1980 PEACE RIVER HYDROMETRIC DAT!~FOR THE 1979....1980 ICE FORMATION PERIOD 1!7/6~ -ACRES IIPom ]8NE;RGY RESO\J1CE;S CCNSERVAl10N BOARD IIDD£O OONVEGAN POWER DEVELOPMENT ICE ANALYSIS .bill!iQ ...OBSERVED LOCATION OF ICI::FRONT. NOTE RECOROED DISCHARGES AT PEACE RIVER ME PRELIMINARY DATA AND MAY NOT BE ACCURATE DURING THE ICE FORMATION PERIOD DUE TO ICE EI'FECTS, LHttlnH'++.J+l.J.+-J-+++-:~ Ilf !t I! ';TI8'++I,H++H+H-t++-H- III f~r:~HlI-l-H-H+H+H l'~ I ttl'+-;4+11-+H+HH-l-+ I " 5 '015202:129 FJ:BRUARY 3' 19BO JANUARYDECEMBER 1979 NOVE MilER 1GOO :!i:)!!!!p Ill!!!!iii!',!!!!!1 II Tp ~n ~~4lII11111l111Iil! I l I III i I j;!I il !I!1 11'I I I I·'r-RECORDED AT PEACE RIVER lTf1Tf11T1TlT11 1 I,'~i!.TMi,cl I 'I I"II I I WATER SURVEY Cl'CAt/ADA,STATION No,07tlAOOl )I''.J-l iJ ".f'....I'JI I!I f 1500 .1:V.i',I.i i ~i 1 .'l!!:1!I't lIt Ii .11 I I "VI II I 11 I f YNl.nlhr.q11 IT :},";'\L f •,Ii II I I ~,-H;i+H+141 -Hl/1+ 1HII+II-H+H 13oo'ivil}111:f'!.lllj'\;II It,',I :,I I'lffiH1111111-'+H+ti I ~!d I I!It lUll II I 'i I I ,III 1200 J''....','.'.'1\.'I.•..,.*1 II i 11II!i lllld!l':I I \I I'II .I,I ' 1100 !1 •,I ,.!.,I I \I!'t1\+1rl--t1l+H1t+-\+H-IH-t+1 :I :I n l!I ,;'I J '~I fAi;,I'11'I I ' , 1000:r;:;;:i:I ,lli,,:j ll,'f!~l';p Ill;~,';Pi!:!"\~:~r ~~-':4+IIJI:llllllm+4m'l1l0~••,,11;1 !iil,i l Ii il 1'....Ul11!11 !Ill ~a ~i-!+III I ;,I I f l!~~;.ff,!,~lh ";,,'!.;ii j'll',1::,;,'j';Il,I;Vi,j ,l!l l Ti,'IAI '\;I l '11:1),.III jT'l 11111~.T ""/',I ,,,'""I I I ,i,In"\It:I ' i ::!,;1 l '~~.H}P 111 q I ':1'\l-t l r.'I lj I hj uu I.I'\:!I I i I '.,~F+t,'j "I :w'11 I: :::;,'.;iL ;;Ii"i;t,j,"~;ln:l !lIn Ii I1nTIrrn;fn r 1PITT1T!\I!lTFntrntm1Tllif 1.llrt~·'~lI I!!rrm -~ex...s e~~~ti 7~ti ~:~~GI 7pQ ~GOO<: t.J ~ tQ-~~o ~~-""...-4008zfE3 -"300ti·~_.t::: '"~>200 EI- 'i=@i:.ql4..1009~ t. 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HOURLY LOAD WRArtON CURVE PLATE C DUNVEGAN IOOMW Z-'83MW 1980 TYPICAL WEEKLY LOAD PATTERN FOR THE ALBERTA INTERCONNECTED POWER SYSTEM IN 1990 LOW FLOW YEAR l~~_1 JUNE ACRES ~PD(ll1 tNERGY RESClJRCES CONSERVATiON BOARD fiUOld DUNVEGAN POWC"R DEVELa"MENT ICE ANALYSiS !:illlt I WEEKLY WAD PAnERN BAstD ON JANUARY 14 TO 20,1974 LOAD P.ATTERN . 2 HOURLY LOAD DURATION CURVE Q£jTAiNEO FROM 1978 ANNUAL STATISTICS REPORT E:lECTRIC UTILITY PLANNING COUNCIL,SYSTEM EVALUATION _~NO "t~IA!lILiTY COMMITTEE. MONDAY TUESDAY WE~Sf':.t ,~Y FRIDAY SATtJROAY SUNDAY I /I../I I 'j v III 1/1I / I(~I\1/011 !\.I~11~1\I '1"1\11\ I II)1\I r"I i I I III I I II NJI i I , I;Ii :J !I I .'. i 11I'!,'1 .1 III III r II !II i I i I J 'tll ,! II I I . f i I I 'II 'i'!~.J:1 1 .1 " ,, J II~f I , II I·!I :i :I I ![.v I.: NORMAL FLOW YfAR MONDAY TUESDAY WEJN:SOAY TI-U'lS!lAY .I1lDAY SATURDAY.SUNtY.Y TYPICAL WEEKLY LOAD PATTERN (1990) aooo 8000 8000 I !I I 1000 1-.I~~l I j I ,I i I I I II 7000 7000 jUI .~~I .,,6000 6000 .,,6000 ~ I;wl ~5000 ~ !:l DU/lVEG~N 900MW !;t ~:ooo 1'-\t ~ 1 I if 1\11 1\J ffi 500) ::<I :::<.f'• 0 I 0 :l ~ooo 1 j :i 4000. i I 4000 ili II I ::IE t '"<>~l I 0 ~3000 .I!I j 1 1 i 3000!j j I I I II 3000 !I !I i II!I I ~ooo .I ~ot 1!COO T I I II '!',II;I . ;:II f ;i 1 I 10liO 1-+- 1 t I'I 'I -I .I '000 1000 ItII!I !OUI'M:GAN 100 MW I I 0-0 0 DUNVEGAN 100 MW 1008060 PE.RCENTAGE OF TIME ~"~ HIGHfLCJN YEAR ., ,,,I l ~Q ~Q. I>\QNOC.Y Tl.I£SDAY 1/;~~ffi.nt.YSATlJRO,!l,~SUNDAY 100 .0 9:)z<l ::l:.... 0 a:80.... ~ ""70 ~ 15 6Q ~ ,5 50 ua: ~ 40 0 o I "1 I ,!I !'et 1000 2;:lt;O 1000 aOOlf I I I II I I I ( I ,I I iii I ,",I Iii I l!!:;0001 11 I IV HIll il I i UJ r:II.':-:\1 !f AI :I j 1 !<i3:-8:.000- ::IE. o :a:~ ~ _1 3000 (:::::::::::~:'. _I&!!!!!I..-i~ _____,~.__....___".~__....__..__~__._...._1:t.~~.",~.,·...c....__~__~__.-__~._~~__~•.-..,.--•.---••-.-_-.•.••,,-,,-,,~,~_c_.~,-_..._".."..........~_.-,.,.,..--_.-------"_..,,. !-II'.'!.FLOW YEAR {NEAll WEEKlY F'llWER RELEASE C1'l32a M3/~C.l NORMA'"FLOW YEAR (MEAN WEEKLY powEll RUEASt OF'94a fA 3 /SEC) LOW FLOW YEAR I MEAN WEEKLY POWER RELEASE OF 6~2 M 3 I SEC' ['..'~ ~~~_6&._ l~ ..W'v': PLATE 2000 o 1000 15000 14000 13000 ;f:• IZOOO 100.. 10000 sooo eooo 1000 /::OUNVEGAN 4':'11')0 /-Ff.A(£Ril;'R~/to. ,.-3000 TH THURSDAY F FAIDAY 5 SATURDAY LEGEND su Sl.tID>iY M ~O'J!JAY T TUESDAY W WEllIIESDAY HOURLY FLOWS FOR A TYPiCAL WEEKLY LOAD PATTERN IN 2005 LOW FLOW YEAR IIPD(D I~NeRGY RESOURCES CONSERVAnON BOARO HUn 0 DUNVEGAN PO'NER DEVELOPMENT ICE ANALYSIS t!QlI HOURt.Y ~OW PATTEIINS SI-I;l\'iN ARt ht'l'flESENTATIVE EXAMFlES 0'T~-RANGE OF HYDROLOGIC ANO OPERATING CONDITIONS COtISID"IitO IN THIS STUDY 1 r !~Ii;~:::r Iv I ,:\I II.'~'..r ~ i ! 'i •A I ~!!~Y ~\~..:lkf+.~:I" MONlJAY TUf~DAY i\'Em';S()AY THl1lSDAY FRIDAY SATUf<!IAY SUNDAY Jell'·185 209 I 210 313 'I~e I Z11 I !•I· I ..~OUNVEGAN 1"1 WOMW I ~~ !;I I ~~i I II.I".~IIII\.AI 1\1\1/ - MON DAY tUESDAY \',WIE$OAY TfUlSOAY FRIDAY SATUAOAY SUNDAY 4000 3000 o 2000 1000 DA1.Y CAPACITY FACTOR ~ .~:::.w<:>a:~u !!lc 4000 o o 3000 ~__~OPtN WATER rooo ___WITH ICE COVER lOOO 15000 15000 14000 140!l1'l 13000 '" 13000... 1;< IZOOO ~IZIlOOm :lO I 11000 "11000~ 10000 ffi INIOO ~ ~ooo ~ooo eooo eooo 7000 1~00 ... Z65 1,,1 SATURDAY SUNDAY NORMAL FLOW YEAR NORMAL FLOW YEAR '300 I :<51 T a3S I ~oo I 'lB. MONDAY TUESQAY WEOOESOAY TfUlSDAY FRiDAY -H-ItH-HHiir--il+tt--fi-H+4Jll.1M+>lLM-4+-A+Jj rooo Mti1mh+1H+HI-A-ffi+-H--4fL'~L.JI..lI+-W-l-.gJ)L.'J 1000 II II I I :I~NVE\'JI.'I I rII ,1/900 MW I lilil N.1 I:: I•t 1I { L \/,~'I ,'II"\I\.w f !til I It \!/. 1 i t:.CWAY TUESDAY WE!lNESOnY TI1\.RSOAy FRDAY SATURDAY SUI'DAY (~mEIOOMW AT DUN\J£GAN ASSUMEO TO BE BASE LOADED IN SYSTEM) 4000 0 1 t t j I!(t I I 1 I I!i !J I It lIt!I!I I , 2000 30Q') 3000 MOtlOA'f TUESDAY WEllI'ESDAY TtrnslJAY FRiflAY SATIJROAY SUNDAY \'::00 4000 1000 :zOOO t'Atl..y CA~AtITY FACT{lIl HOURLY FLOW PATTERNS FOR OPEN WATER CONDITIONS tiILl...~<t~ ~Iei~Oil: a~~, li3 1Il ~::<. ~ ~u .~ ·I£I\CE M'ER ~:;'\J 40=0 2(!CO 1000 TYPICAL WEEKLY LOAD ?J.~TTERN FOR THE ALBERTA INTECONNECTED POWER SYSTEM IN 2005 ...It.-.~ "'-'-"'-OUNVt:GAN (PEAce:RIVER ASSUW£O 10 BE ICE COVEm:O 10 THE VICINITY a"111EWNvEGAN TAlLRAce:) HIGH FLOW YEAR HIGH FLOW YEAR MorlQAY TUt;5llAY WEct£.SCi:t(TIWSOtlY FR'"...AY SAI1.JlillAY S\JNo.W 417 I 3BZ.l 513 .~"~4 I 5~I a16 I 34e Mct;llAY ltEStJi,\(\'t~TIUl:;O.\Y mDAY SATUR!lAYSUNoAY ~()'EN WI\TER 4000 aooo ___WllHk:E ~COVER 2000 1000 oo EFFECT OF AN ICE COVER (X\J HOURLY FLOW PATTERNS AT THE IQWN OF PEACE RIVER 30:1:' MONDAY TllE5Df.Y \\'Etf£$tl/(f THIJRSI).'Y FRit.t.Y SATIJROAY SUNDAY 4000 -4000 i I;J iii I t I 3ll~O j---,;,--;x;+~r+-"'l7"'l+7--m--;=;n+.::~;'+------i=rl 2ll:l0 H+IH#¥~:+t-H'n++'-lM+lTH±-fHc----iLI--++'!Ht-++ lOOO IOC:! G 0 tow tAl~T CAPACITy fACTO<! 15000.r-T"""""I~15000 15000 HooO I I 14000 1400<:1, III 1 il,30CO1300<:1 1II1 1\II I 1300<:1~I 'ill I I ~...OOWEGAN :\IZOOO .!;t.~I l'i i ;'900MW ~~IZOOO .1 t _~II I m IZOOO I I •:lO•!I0 0~.11000 1d I J I 1IUOO z 11000 w.I '11 !II j I g0IIc,15 10000 IVl II 10000 '"10000IlItII,I~II w2V-'I I ~~I I II .a.. '000 '000 ~ooolI·,j !I !j III \.t I'll'1 III!I I 500;)H-+I j'~ BJOOII•DOOOI:.1,I I I'!I'J 17(\007000IIjI 7000 .~ ~~<t:;: W j .~~ 5a: '!!!wn~ ~ '-'w U'l ~:::•w .~ 5 U'l E t~..?~::J JUNE Igao l D jL- -__-----===~===--.,--------....---.-..L------~____=I - 10 PEACE RIVER WATER TEMPERATURE DATA PLATE E 2 10 9 8 7 ~:; tTl6::0 ;;l :;;:: ill ::0 ~4 c :0 ", 3 -; £; 9 e o 7 '"~ tTl6:ll iil 5 ~ ~ ~4 c ill 3 ? £; 2 o IJ~lm J::NE:GY ~~~R~~~~~~~~~l1QN ..~ARD MARCH MARCH MAR 5 10 1520 25 MARCH FEBRUARY FEBRUARY FEBRUARY 5 IQ 152025 •FEBRUARY JANUARY JANUARY JANUARY J 510152025 JANUARY DEC~MBER RECORDED AND COMPUTED WATER TEMPERATURES AT SITE C 19I1. DECEMBER DECEMBER RECORDED AND COMPUTED WATER TEMPERATURES AT SITE C 1977/78 w 10 15 20 25 DECEMBER NOVEMBER NOVEMBER 5101';2025 NOVEMBER -,-._.----25 :5 _____-~_..-._--- - -COMPUTED i --RECORDED ..(V .JI 1\~~~M r .~WJ'V 'JV w 1:1 WV . r .....___..._•.•..--25 a:.....·IC ~~JI!.......,...__._.......----~ _.25 S _.,--_........¥,10.1 .1""cv ~;;J . "--""I'\S ~ _. \.V;Ji'~---COMPUTED ---RECORDED\. l .... V\'~)}'i\ \J~A ..n LY:A.j.rV" \/ . . -.~.~ 10 ~ 9 e ,0 E 7 o W £> tl: ;:) ,~tl:5 LLJa- il]4.... tl:LLJ 3 \i?:2 10 10 9 €f" 8 8 7 ~U 7::;~ 6 g}llJ 6 ~tl: ",~5 .E::<t :;"a:m LLJ::0 a- 4 ~:::E LLJC....::0 l'I 3 -;a:3LLJS~~2 2 o e o nl'l~ rV~-1]f ../-.....,.-='-""=..ry-- 5 10 'i;2b .25 MARCH ,PORTAGe IMOUNTAIN !(GM.SHRUM TAILRACE) FEBRUARY MARCH :5 lOIS 20 25 5 10 13 20 25 5 10 IS ,2025'5 10 15 20 25 FEBRUARY MARCH 5 lOIS 2025 •FEBRUARY ~I:' JANUARY 51015202:1 510152025 JANUARY 5nJ:\?025 JANUARY DECEMBER 51015 20 25 5 n J5::Ois DECEMBER O~CEMliER SIO 15 20 .25 5n IS 20 25 DECEMB~R RECORDED WATER TEMPERATURES AT PORTAGI="MOUNTAIN AND PE/lCE CANYON 1977 RECORDED WATER TEMPERATURES AT PORTAGE MOUNTAIN AND PEACE CANYON 1977/78 NOVEMBER 510 15 2025 :;10 152025 NOVEMSER NOVEMBER s '0 ,1$20 25 51015 20 25 NOVEMBER 10 I I ---L-~-i- nl II~II I W 6 I~.I +._-~4 1 '.I'I I 9 -:1 - o I ~ 10 :.'\T I -I I ~g "~,PORTAGE MOUNTAIN 7 '""........../(GMSHRUII TAILRACE)f T L ~/---.7.~ W 6 !'L'6 ::0 Cl:\•~.~~'5 "5.~ ~'4\-I\,\.E :'\.'\4 ~ W 3 ~\\J\3-;~.S 3'h ~ 2 '~"1-<"'-:J --\"""2PEACECANYONSITEll"~\V v-. .\f'\~j\7l I I o I I '\J kr...J 1 tl:3W~ 1 ~2 I--------~------~======~---------------:..~..-------------------., ~~ ,...,\00'"• .,. <.01 ,~~tt -I'•..•.••Ao r -.......'1J:.~•..;.....,..,i'","I ~\....~~9.!r..0Io0o--~:,.'•::" --"-.....,.-..--_.-._.•_.--~--~--~-.~-'".._•.._.._~..•.,._.-._.--.--------.-.--..-.-.~.;-~---"--~-c::·_-___,--_-.._.-_-_.-._.-._'..11_..-=_.__~~._.__=._-'l~:,-~__.._._...._~_~_..._~_.,;.....'______.._~~__._,~,...:..~ ~. ~ ~,k(, .;I~.J iJ Ct,n F PLATE 1980JUNE .' 30 WEST PEACE RIVER DYKE o PEACE RIVER PLAN AND PROFILE IN ,THE VICINITY OF THE TOWN OF PEACE RIVER. s ". I.PDl'IE1~ERGY RESJURCES C(NSERV~ThJN BOAAOflundDUNVEGANPOWERDEVELOPMENTICEANALYSIS c:=;;-'" SCALE IN KILOMETRES 30 J. '",-: •~HEART RIVER '/"'-.~I .~ , ",,:1 A(·····~:>2 ''''.'•....,~..:..-?:-"<./ --..,',,,',~.Ii..,"/ .,;/# '.~ ffl lr... W::: ~ z ~w -'w 330 320 310 300 10 '")~. / }.~, J;:}A~,,«--:..;,. 8 97 --.~ ~I;NING OF PROFILE 65 "I< 4 f l'ROPOSro OYKE ELCVATIJN i ALONG EAST BANK i PLAN 32 III, PROFILE .PEACE F!tYER TOWN !-tMITS SHAFTESBURY fERRY r- UNDERSIDE Of'ICE COVEll ESTiMATEO MEAN ./--R1VERflEl)PROFILE/'. G711 RlVEROSTANCEIN KILOlolETllES fROM HIGHWAY N.,Z BRiDGE CROSSlNG ......--.... <~.-.;~~'-' 9 tlAR 6Rl~G£-,HIGHWAY No<!ERlDGE CQ,1I'LlT£D ICE PROflLE:.ElOSTIN'i 0Yl<£.aE'l:tm.ON...r·.·HEART f 1-wS C Gt.UGEFORADiSCHARGE'2500 M'3/SEC AlONG WEST BANK.",'.R1VER Jt .No.07H'001 \ I WEST PEACE RlVERl '.,-~-------_..J;L......_-~~::=::~~~::'7i='~t=""'~·~::;·:dL=-=-____.::._~ :.._".SMOKY RIVER !laTA ... 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I "",U'"I ....''1'..::---".•....'.'.-.,'......"~,,,,.A ...,'~~>;"...':J,...'.I'"-.,.-,~".'".'~"J',..'{"'".";."{./,,'.........',,,:.,~.".'f',"./\,.',.1;';"F :;'/''-,.',1"...,.~.......:.I ',,;,...'....."\...(l' '..":'..j){'-,-'c'..ii'"'-.i '-...t'.'i ..;·.::r-··'\.,','1~..."'"".'....''',-;..:........,j..........."..'i/".",..,,"~7"~'.."...'.;<t",.'-1.;-..~/,";-~j':/.......,,f '.././','•.....L'"'....; •~"A ~.'...:.""'-L 300 III ::320... :l: ~ Zo i= <[ ~310 -'.... ~=====:;::==================__-====-____________________/'~..4 0 .~/,.b(;"1.~~_ ___._'_...._~._._..~,.;-~~t ...-.,.._..,-__.========;============:=========-="J---ACRES----,j I -~'....,'.'.'>"~.;S ">.',~._';c'.,.':....~"•.••;';.J ";...',.'.'.....-,.:,'..."•.';1 ..·.···".... <,~,~~~-"._.,__,..,;.C__,.,.;,......;,.;.,~~.'-:':'"_~,,~.J1i-_ , ~ § '"~ '"o -"'5 I""010~I'I -00'."" ?<r-; '"5 DUNVEGAN 20 j I I 3.NORMAL FLOW-WARM TEMPERATURES--"'- I I ---1+--.~-+.t~-,-1-----J<a ALBERTA-BeV-I .I BORDER oW 5 IS 25 515 25 5 15 25 :;15 25 5 15 25 NOVEMBER otCEMBER JANUARY fEBRUARY MARCH ~·:c '7(. aoo l!; 5152551525515255152551525 NO~DECEMBER JANiJARY FEBRUARY MARCH 6.LOW FLOW -WARM TEMPERATURES 1~1~llENERGY RESO~RCES CONSERVATIoN BoARD ~ ~ ~ '3. 15 5::; d~> 1;: fi: iI III !!lilT III I 700 l :::Ii "[I , ,.-..j ,.;mt'.t f •' L :;I •I .l [1.·/!ALBERTA-B.C. 600 ~t.:''.'I''I'i I BORDER,'I ., I,'I ,!;l !;i iT 500 L j -l-l'1'.'1 OONVEGA~1 !I' ~.L/1 ,.:[1:TT: w%i 7',l-o-FEa:,,,,.oa /:j I I I 'ACE Ri\lER~I!if I'i I ....:-1::>i Vi.;I "!I ...'f i I I 'I5m~:i:IIex:I .."1.~•f-..../1/1',:' "l~I -....-:I I ,i~200 .i j ,I; t)I''''-,I .I j I 1 fi ·.f R'~I ,I 1'1 9 '00 II \J'I j .'I, I if ...If,•:y".Ii!I I oili,!f,l i,.II{,II ,ili l liL 0 :; G::O • 5;v t=t:.j---'-.I ::l;I '"~:~4:0 tI1n. o "'''''....~. o·"••·" Q'·..~~>-~5 •• 9"'.:~g-" -<5 '";;l 3 o § ~o :tt;~'"~15 11> ~ x~ ill ;:'" -0a.." !Co '" 5 ~ DUNVEGAN ALatRTA-B.C, .BORDER I I I !I f<I PEACE RIVER NOVEMBEROECEPI.BER .JANUARy fEBRUARY ~1525515Z::51S.551525 iii Ii'"I Ii.I 5 <525 S 1525 5 .~~5 5 1525 51525 MlVEMBER DECEMBER JANUARY FEBRUARY MARCH 5.ENVELOPE CURVES FOR NORMAL FLOW (08SERVED DATA) ~152$51525 5 1~~5:;15255 1525 NOVEMIlER OECEMBER JANUARY FEBRUAR'r MARCH 2.NORMAL FLOW -NORMAL TEMPEF:ATURES o I I;fil'l!t I I I I I I;11 j'I I I loa f-----H+-I II JOol Illd I I~I 600 800 ~cn 1---I f Ii I 5DO I I I I I' 600 I I Y I ,:~I 'I ..,.I I 700 I Ii!I ,P' l:l :; 5:; ~> ~ NOVEMBER'OECEMB£R JAt~lJARt FEBRlJARY MARCH :;1525 ~1525 :;1S.'5 515 2551525 800 !.I .1 1111 I I I I II III !I .I I 100,"I .,I 'I , ,I ,I ,.'i'1<1.ALBERTA~B.C.'I.'.:.I d II ~.''I Y.L 1 I.'BORDERII,Iii!,,~/'-t-I-1'H'-H-'-I-l-;...H4-l nil Ii )I iyf '~ill 11 '"-;•OIi'lVEGAN j :,'I •i r /IL r !jl -,-I 500,!1/III'J '/'!: =t _l'-~I .,!PEACE RIVER~::l!1 I I Ia:x ~oo -;-.,,20 ~!K \1 H l'lil, 5 ~o ~k\I:'!i-Hll:R I !,':f ;II IllJ,,~~,' J.!'/-...1 '";I :j &200 1/l\!I :i I~!J l'-~lll d ' 9 10C l-1/I ~,l 1 . Ii .,Iii,Lj 1i.~~WJ :J \1 l5 ::l; .~.:Ea:x 4CO I J"Ii!•/'I !' ::> a ::J ~ ~ l;: fi: :; ... .~....., ~ & ti~.;J ~ o ." AL&llT4-B.C. BOROER p .~ 9~ Ii),-f'l -"'0 0-"~~ ~. o 5 ();; '"".m o~.." P~x.z 10 .::,g -"'0g~ -<a '";: ~ :D :; 15 MARCH I '14FEACE:WfER OBSERVED DATA NOVEMB£R OECEMeER "1$<551525 I-H--"I I::t-.I.-f;=.i 'I I i l-l-t I I j J i I J.DUNVEGAN 0"1 'I'1il"'j'f1c:=+-+'t"''1 o I I 11 I t I !J lIt I ,!,-,t '=t::==+-+l I :!~-iJI S Ci2$:;1525:;'52$$'52551525 NOVEMl3E.ROECEMBER JANUARY ~E!l1lUARY M4RCH l NORMAL FLOW -COLD TEMPERATURES aGO i 'i Ii'i , $COl I 'I I.Ie l:>o .....-q-I X'O,I I •I fl'r!1 I 'I •. I •I I II "I", I ,.'I I1O:JI,:,~1 .~"'i' 600 I I 1 V I I 1;,.!I 1 I:::i=I zoo I I .H \\1 I 1 I .';I 1"t I ~o I .!I I U 11 "II If I II i 70°11 i i!1i I ';11 ..71'1 ill!'!1111::!I ~ ::l; ~~"co 1----+I I J(;I I I 2(; t; Q,::> ~3Ctll IIPi II!f!: 'fE UJ\l &20°1 I •t/:'~l I ':I Ia ~g It~1 HA z 3 -~ l:l::>- ~e :; ~ ~- --~PORTAGE MOUNTAINANO P~ACECANYON ---PORTAGE MOUNTAIN,PEACE CANYON,sITe C,ANO,DUNVEGAN LEGl:NO 4.HIGH FLOW -COLD TEMPERATURES 5 1525 ~'5Z3 S is 25 ~1~25 5 lS2S tJOVEMB£R OEC!:~BEF .JANlJARY fEBRUll.fty MARCH ~ NOVEMBER OEC£M!l£R JANUARy ~C;<5 ~1525:<Ci25 800 I II ,1I I I I II I I 1 I !1 ! .~~4 col':"i it rIll j~111!•!r:ACE RlVER §- ,..J 5 :J ,,}, ::l; l!i 6001 IVI "I';IllIj'l;;~__,,t.',_I 1 ~ IE tl & I :::~:;:o ~;;II "ICE COVER DEVELOPMENT 6 1975"1976 •"ON THE PEACE RIVER'"1916"1971 II •.I a "'"137.• •t•197a ..1979 • •_7 r::;.'PLATEL·1979 •1~•._~~~~]J~NE1980 LG J--_.-_..,._-_.-.-_._._--.------~--_._..__..•__--•.. r"'"